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[Display omitted] In the adsorption process of functionalized layered double hydroxide (LDH) to target pollutants it, is essential to investigate the role of functional groups. In this work, 2‑mercaptoethane sulfonic acid (MS) was used as an intercalation modifier to prepare functionalized NiFe-LDH by solvothermal method. The interfacial interaction between the functional groups and the NiFe-LDH surface was studied via molecular dynamics simulation. During the intercalation process, the more negatively charged sulfonic acid group tends to self-assemble electrostatically with the LDH laminate, while the sulfhydryl group is involved in complexing heavy metal ions. The adsorption experiments showed that the adsorption performance of the adsorbent for the three ions of Cd2+, Mn2+, and Co2+ at 298.15 K was 266.16 mg/g, 175.60 mg/g, and 106.56 mg/g, respectively, which were 10 times, 8.7 times, and 4.9 times higher than that of unmodified NiFe-LDH. Meanwhile, Multiwfn wavefunction analysis combined Visual Molecular Dynamics (VMD) was applied to analyze and visualize the reaction active sites & the interactions between MS and NiFe-LDH, and the complexation of the functional group of MS with metal ions, to insight the role of the functional groups in MS molecule, and to reveal the cause that the adsorption capacity of modified NiFe-LDH for heavy metals greatly improves from the view of atoms. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe-DP was first applied in the detection of organophophonates. • Fe-DP had highly selectivity and sensitivity for trace determination of DTPMP. • The micro-mechanism of fluorescence quenching was revealed. Diethylenetriamine pentamethylene phosphonic acid (DTPMP) is one of the most commonly used amino organic phosphonates. The existing methods for DTPMP detection are complicated, time-consuming, and cannot detect trace DTPMP in the natural environment. In the present work, the Fe-based 3,5-dimethyl pyrazole fluorescent sensor (Fe-DP) was constructed. The addition of Fe3+ to DP solution can greatly decrease the fluorescent intensity of DP, while the addition of different concentrations of DTPMP will restore the fluorescence intensity of DP to different degrees, to achieve quantitative detection of DTPMP, and the detection limit (LOD) of DTPMP was lower as 0.105 μΜ. The Fe-DP fluorescent sensor exhibited excellent anti-interference ability and good stability. Moreover, the fluorescence quenching mechanism of DP by Fe3+ was revealed by UV absorption spectrum and Multiwfn wavefunction analysis based on density function theory (DFT). The results revealed that the excitation of DP belonged to local excitation, in which the electrons were donated primarily by the N atom with double bond and redistributed within the pyrazole ring. The fluorescence quenching of adding Fe3+ was not caused by resonance energy transfer or charge transfer, which did not belong to dynamic quenching, but due to the ground state complex formed by the coordination of Fe3+ and the double bond N atom on the DP pyrazole ring. [ABSTRACT FROM AUTHOR]

A simple co-precipitation method was used to synthesize ibandronate nano-functionalized hydroxyapatite (IB-HAP) and used for the removal of Pb2+/Cu2+ and chlortetracycline. The effects of the amount of modifier IB added, the initial concentration and the pH value of the solution on the adsorption effect of heavy metal ions were investigated. When the P atom in IB accounts for 5% of the total phosphorus, the adsorption capacity of IB-HAP was 1565.3 mg/g (Pb2+) and 246.71 mg/g (Cu2+), respectively. By adding heavy metal ions and chlortetracycline (CTC) in different addition sequences, the co-adsorption effect of various pollutants on IB-HAP was studied. According to microstructure analysis and simulation, the adsorption mechanism was studied from a microscopic point of view. It is the first time that modifiers and pollutants were used as central molecules to study the interaction sites and interaction strengths with surrounding molecules in a wholly covered state by Hirshfeld surface analysis. Finally, the desorption experiments showed that IB-HAP had strong regeneration and sustainability. These results showed that IB-HAP was a potential adsorbent, and this study also provided new guidelines and valuable methods for analyzing the mechanism of co-adsorption of heavy metal ions and antibiotics. [Display omitted] • IB-HAP was synthesized, and its single adsorption capacity was 1565.3(Pb2+) and 246.71(Cu2+) mg/g, respectively. • Different addition sequences would affect the co-adsorption effect of Cu2+/Pb2+ and chlortetracycline. • The interactions in completely surrounded states were firstly studied by Hirshfeld surface analyses. • Hydrogen bond and coordination interaction were the main force for the adsorption process. • IB-HAP had strong regeneration and sustainability. [ABSTRACT FROM AUTHOR]

Our previous studies have shown that the modification of hydroxyapatite with organic phosphonates can greatly improve the adsorption effect of hydroxyapatite on heavy metal ion pollutants. Hydroxyethylydene-1,1-diphosphonate (HEDP) is a widely used multi-purpose chemical agent with the advantage of lower-cost, but the preparation and application of hydroxyapatite composites doped by HEDP have not been reported. Therefore, in the present work, calcium nitrate and diammonium hydrogen phosphate were used as the calcium source and inorganic phosphorus source, respectively. 5%, 10%, 20% and 25% HEDP was added as an organophosphine source in the process of preparing hydroxyapatite （HAP）to obtain inorganic-organic phosphorus hybrid HAP composite materials with different HEDP doping amounts, respectively. XRD characterization showed that when HEDP doping was 20% of total phosphorus, the crystallinity of the resulting composite material was greatly reduced and became amorphous HAP, and the maximum adsorption capacity of the obtained amorphous HAP was 1893.7 mg/g, 239.3 mg/g, 285.4 mg/g, and 339.7 mg/g for Pb2+, Cu2+, Zn2+ and Cd2+, respectively, which was 8.47, 4.25, 3.29, 3.41 times that of the commercial HAP, respectively. Furthermore, Hirshfeld surface analysis specially including fingerprint plot was applied to investigate the interaction between HEDP and HAP, and reduced density gradient (RDG) method was carried out to explore the interaction mechanism of HEDP doping amorphous HAP composite and heavy metal ions. Because of the low price of HEDP, the simple and low-consumption preparation method and the excellent removal effect to various heavy metal pollutants, the inorganic-organic phosphorus hybrid amorphous HEDP-HAP composite material will have broad application prospects in the field of heavy metal pollution control. [Display omitted] • Inorganic-organic phosphorus hybrid amorphous HEDP-HAP was synthesized. • The adsorption capacity of HAP-H-2.0 was much higher than that of HAP. • Hirshfeld surface analysis combined fingerprint plot were applied. • RDG was firstly used to reveal the interaction mechanism among different fragments. [ABSTRACT FROM AUTHOR]

• Cu-MOF-74 was first applied in the detection of organophophonates. • Cu-MOF-74 had highly selectivity and sensitivity for rapid determination of ATMP. • The fluorescence intensity of Cu-MOF-74 increased 24.2 times by adding 90 μΜ ATMP. • The mechanism of action between Cu-MOF-74 and ATMP was firstly revealed. Due to the lack of rapid and efficient detection methods for the determination of trace organic phosphonate concentrations in the natural aqueous system, little is known about their impact on the ecosystem. Amino trimethylene phosphonic acid (ATMP) is an organic phosphonate that has been widely used in many fields. In the present work, the copper-based organic framework material (Cu-MOF-74) for the specific detection of amino trimethylene phosphonic acid (ATMP) in aqueous solution was prepared by hydrothermal synthesis using 2,5-dihydroxyterephthalic acid (DHTP) as raw material and copper nitrate trihydrate as metal source. The synthesized material can be used as a "turn-on" fluorescent sensor for the specific sensing of ATMP, the fluorescence intensity of Cu-MOF-74 can be enhanced 24.2 times by ATMP (90 μΜ), the emission wavelength of the fluorescence emission spectrum of the system was blue-shifted, and the detection limit (LOD) of ATMP was 0.844 μΜ. Moreover, the mechanism of ATMP greatly increasing the fluorescence intensity of Cu-MOF-74 was investigated by experimental and theoretical calculations of quantum chemistry. The experimental results showed that ATMP was involved in the coordination of open metal sites in Cu-MOF-74. Multiwfn wavefunction analysis results demonstrated that the charge transfer from the benzene ring and hydroxyl groups of the ligand to the metal (LMCT) occurred during the electron excitation of Cu-MOF-74, but after adding ATMP, the coordination of ATMP with copper led to the interruption and reduction of the energy transfer and electron transfer from ligand DHTP to Cu2+, and the fluorescence intensity of Cu-MOF-74 was improved. The Cu-MOF-74 fluorescent probe exhibited excellent anti-interference ability, high selectivity, good fluorescence intensity stability in the short term, so it can be used as a reliable fluorescent probe for the highly specific detection of low concentration ATMP, the revealed microscopic mechanism of Cu-MOF-74 fluorescent probe to ATMP from the atomic level can provide a theoretical basis for the research of new fluorescence detectors. [ABSTRACT FROM AUTHOR]

Amino trimethylposphonate(ATMP) functionalized HAP were synthesized with different ATMP addition (0, 5%, 10%, 15%) and the adsorption performance towards Pb2+ and Cd2+ were studied in an aqueous solution. Under the optimum condition, HAP with ATMP addition of 10% (10AT-HAP) displayed the most efficient adsorption performance with the adsorption capacity of 1458.79 mg/g and 321.26 mg/g towards Pb2+ and Cd2+, respectively, which improved 76% and 92% than that of the artificially prepared HAP in the laboratory, respectively. For both heavy metal ions, the adsorption mechanism also included ion exchange and surface complexation, in which the surface complexation played a predominant role. In addition, XRD showed that a new crystal phase was formed after Pb2+ adsorption, while no new phase appeared after Cd2+ adsorption, indicating that the adsorption mechanism of Pb2+ involved dissolution-precipitation. The fitting results of adsorption isotherm and kinetics showed that the adsorption of Pb2+ and Cd2+ on HAP and 10AT-HAP were well fitted by the Langmuir isotherm model and Pseudo-second model. Moreover, Multiwfn wavefunction program based on density functional theory (DFT) was applied to deeply probe and vividly visualize the interaction sites, interaction types, interaction strength and the essence of interactions between HAP and ATMP or ATMP-HAP composite and heavy metal ions. [Display omitted] • The adsorption capacity of 10AT-HAP on Pb2+ and Cd2+ reached 1458.79 and 321.26 mg/g. • The adsorption mechanisms were revealed by experiment and Multiwfn program. • ATMP formed ternary complex with HAP and heavy metal ions. • The oxygen atoms of the phosphate groups of ATMP played a major complexation role. [ABSTRACT FROM AUTHOR]

The corresponding adsorption mechanism of the adsorbent in the process of adsorbing phosphate. As shown, three adsorption mechanisms of the adsorbent in the process of adsorbing phosphate: 1: The combination of PO 4 3− and La3+ produces LaPO 4 with smaller Ksp. 2: H 2 PO 4 − and HPO 4 2− enters the interlayer through a substitution reaction with OH− between the LDH layers to realize the adsorption of phosphate. 3: The electrostatic mutual attraction between quercetin and phosphate realizes the adsorption of phosphate. [Display omitted] Severe water eutrophication due to large releases of phosphorus has become a worldwide environmental problem. Adsorption active sites is less of traditional adsorbents in the phosphorus removal process resulting in low removal efficiency, so the new high-efficiency phosphorus removal adsorbents become an effective way to solve the problem. In this work, quercetin modified MnFe layered double hydrotalcite three-dimensional composites structures encapsulated by lanthanum (La(III)) nanoparticles (QLa@MnFe-LDH) were successfully prepared by a classical hydrothermal method. The results of the adsorption experiments show that La(III) nanosphere-encapsulated MnFe-LDH provides a more adequate binding site for phosphate adsorption. The adsorption performance of QLa@MnFe-LDH for phosphate was outstanding, the maximum adsorption capacity was 346.5 mg/g at 298.15 K, which was 300 % higher than that of MnFe-LDH. Moreover, QLa@MnFe-LDH retained its high adsorption capacity (>315.5 mg/g) over a wide range of pH (4.0 ∼ 7.0). The active sites of the reactions were predicted by Multiwfn and Visual Molecular Dynamics (VMD), and novel visualization studies of weak interactions were applied to theoretical studies. The modified MnFe-LDH encapsulated by La nanospheres has a strong adsorption capacity for phosphate adsorption. Therefore, the modified QLa@MnFe-LDH was expected to become an effective adsorption material for phosphorus removal. [ABSTRACT FROM AUTHOR]

[Display omitted] • Environmentally friendly D-Mt composite is prepared. • The adsorption of AMP and AMX by D-Mt-1.4 under different conditions was studied. • DFT was applied to quantitatively analyze the molecular surface of AMP and AMX. • Multiwfn program was applied to quantitatively analyze the molecule surface. The quaternary ammonium surfactant-dodecyl benzyl ammonium chloride (DDBAC) was applied to modify Ca-montmorillonite (Ca-Mt) to obtain organo D-Mt that was used as the adsorbent for micropollutants-ampicillin (AMP) and amoxicillin (AMX). The XRD characterization indicated that DDBAC intercalated the interlayer space of Ca-Mt. When the amount of modifier was 1.4 CEC, the basal spacing enlarged from 1.53 nm to 2.97 nm, and the arrangement of modifier molecules were sloped in the interlayer of Ca-Mt along the longest axis. The saturated adsorption capacity of D-Mt-1.4 for AMP and AMX was 30.86 mg/g and 13.29 mg/g, respectively, while the saturated adsorption capacity of Ca-Mt for two contaminants was only 0.36 mg/g and 0.16 mg/g, respectively. The adsorption of the two pollutants was more consistent with Freundlich adsorption isotherm second-order kinetic model, and the thermodynamic study suggested that adsorption was more likely to occur at higher temperatures, which means that the adsorption of two pollutants was a spontaneous endothermic process. Moreover, Multiwfn wavefunction program based on Density Functional Theory (DFT) was applied to reveal the microadsorption mechanism of D-Mt to two pollutant molecules. This work confirmed that Ca-Mt functionalized by DDBAC was promising adsorbents for micro-contaminants of antibiotics and the insight of the adsorption mechanism from the atomic level, providing theoretical guidance for architecting high performance adsorbent. [ABSTRACT FROM AUTHOR]

Benzyldimethylhexadecylammonium chloride (HDBAC) modified montmorillonite was synthesized and the compounds were used for the adsorption of diclofenac sodium (DCF) and ibuprofen (IBU). The adsorption effect was the best when the best dosage of the HDBAC was 1.6 CEC (cation exchange capacity). The adsorption capacity (q e) of H-Mt-1.6 for DCF and IBU was 125.55 mg/g and 81.64 mg/g, respectively. The q e of Ca-Mt for DCF and IBU was 54.02 mg/g and 13.14 mg/g, respectively. H-Mt-1.6 had higher adsorption effect than Ca-Mt. The adsorption process of H-Mt-1.6 on DCF followed the Langmuir adsorption model and the adsorption process of IBU followed the Freundlich adsorption model. The equilibrium could be reached after 120 min. The adsorption process of H-Mt-1.6 on DCF and IBU followed a pseudo-second-order kinetic model. The adsorption on DCF was endothermic, while adsorption on IBU was exothermic. [Display omitted] [ABSTRACT FROM AUTHOR]

Co2+‐ZIF‐67 metal‐organic framework nanoparticles (NMOFs), act as nanozymes catalyzing diverse processes, including peroxidase, oxidase, and catalase activities. Peroxidase activities are reflected by the nanozyme‐catalyzed H2O2 oxidation of dopamine to aminochrome, the H2O2 oxidation of NADH to NAD+, the H2O2‐catalyzed generation of chemiluminescence through oxidation of luminol, and the H2O2‐mediated oxidation of aniline to polyaniline. Oxidase activities of the nanozyme are demonstrated by the Co2+‐ZIF‐67 NMOFs catalyzed aerobic oxidation of dopamine to aminochrome and of NADH to NAD+, and catalase activities of the nanozyme are reflected by the catalytic decomposition of H2O2. Moreover, the Co2+‐ZIF‐67 catalyzed oxidation of aniline to polyaniline (PAN) by H2O2 is accompanied by the coating of NMOFs with PAN to yield a Co2+‐ZIF‐67/PAN hybrid material. Coating the particles in the presence of guest substrates leads to molecular imprinted PAN matrices revealing enhanced ZIF‐67 catalyzed transformations as compared to non‐imprinted PAN matrices. This is demonstrated by imprinting of 2,2′‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid), ABTS2−, in the PAN coating and the 3.3‐fold enhanced catalyzed oxidation of ABTS2− by H2O2, as compared to the non‐imprinted PAN hybrid composite. Moreover, imprinting of L‐/D‐DOPA in the PAN coating of Co2+‐ZIF‐67 NMOFs leads to chiro‐selective H2O2‐guided oxidation of L‐/D‐DOPA to dopachrome by the NMOFs/PAN composite. [ABSTRACT FROM AUTHOR]

The spent electroless nickel plating (SENP) solution comprises abundant complexed nickel, hypophosphite, and phosphite ions, alongside scant organic additives. In this study, we introduced an innovative method that uses a combination of alkali and heat treatment-activated PMS to disrupt the nickel ion complexation, facilitating hypophosphite and phosphite oxidation, and the alkali acts as a precipitant for nickel. Consequently, nickel and phosphorus precipitated sequentially, enabling their efficient separation and recovery. With a 4 g L−1 PMS dose, the hypophosphite (H2PO2−) and phosphite (HPO32−) conversion rates reached 100% and 99.69%, respectively. After the precipitation and separation of the concentrated SENP solution, residual nickel and phosphorus levels significantly dropped to 10.91 mg L−1 and 12.29 mg L−1, respectively. Subsequently, capacitive deionization (CDI) concurrently removed nickel and phosphorus to comply with emission standard GB39731-2020. Under optimal conditions, nickel and total phosphorus removal efficiency reached 96.69% and 93.62%, respectively, and the residual concentration decreased to 0.36 mg L−1 and 0.78 mg L−1, respectively. This innovative, streamlined strategy was proposed for the green treatment and recovery of nickel and phosphorus resources from spent electroless nickel plating solutions. [ABSTRACT FROM AUTHOR]

[Display omitted] • ACNF/PPy/MIL-100-Fe with stable 3D-supporting skeleton and hierarchical porous structure was fabricated. • ACNF/PPy/MIL-100-Fe possessed admirable adsorption capacity, adsorption kinetics and reusability. • Easy-to-recyclable "electrode-type" ACF/PPy/MIL-100-Fe was redesigned achieving prominent adsorption performance. • Deductive uptake mechanism was electrostatic, hydrogen bonding and π–π interaction. Developing advanced adsorbents for removing the alarming level of pharmaceuticals active compounds (PhACs) pollution is an urgent task for environmental treatment. Herein, a novel acid-treated carbon nanofiber/polypyrrole/MIL-100-Fe (ACNF/PPy/MIL-100-Fe) with stable 3D-supporting skeleton and hierarchical porous structure had been fabricated to erasure ceftriaxone (CEF) and indomethacin (IDM) from aqueous solution. ACNF as scaffold achieved the highly uniform growth of MIL-100-Fe and PPy. Viewing the large BET surface area (S BET , 999.7 m2/g), highly exposed accessible active sites and copious functional groups, ACNF/PPy/MIL-100-Fe separately showed an excellent adsorption capacity for CEF (294.7 mg/g) and IDM (751.8 mg/g), outstripping the most previously reported adsorbents. Moreover, ACNF/PPy/MIL-100-Fe reached rapid adsorption kinetics and standout reusability property. Further, the redesigned easy-to-recyclable ACF/PPy/MIL-100-Fe inspired by the electrode formation craft achieved prominent adsorption capacity and good reusability property. The adsorption mechanism was evaluated via Fourier transformed infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The outcomes revealed that the splendid adsorption capability mainly depended on the electrostatic interactions, hydrogen bonding and π-π interactions. This work sheds light on one facile practical strategy to exploit advanced materials in water environmental remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] The tunable porous structure of metal organic frameworks (MOFs) plays a crucial role in determining their adsorption performance. In this study, we developed and employed a strategy involving monocarboxylic acid assistance to synthesize a series of zirconium-based MOFs (UiO-66-F 4) for the removal of aqueous phthalic acid esters (PAEs). The adsorption mechanisms were investigated by combining batch experiments, characterization and theoretical simulation. By adjusting the affecting factors (i.e., initial concentration, pH values, temperature, contact time and interfering substance), the adsorption behavior was confirmed as a spontaneous and exothermic chemisorption process. The Langmuir model provided a good fit, and the maximum expected adsorption capacity of di- n -butyl phthalate (DnBP) on UiO-66-F 4 (PA) was calculated to be 530.42 mg·g−1. Besides, through carrying out the molecular dynamics (MD) simulation, the multistage adsorption process in the form of DnBP clusters was revealed on a microcosmic scale. The independent gradient model (IGM) method showed the types of weak interactions of inter-fragments or between DnBP and UiO-66-F 4. Furthermore, the synthesized UiO-66-F 4 displayed excellent removal efficiency (>96 % after 5 cycles), satisfactory chemical stability and reusability in the regeneration process. Hence, the modulated UiO-66-F 4 will be regarded as a promising adsorbent for PAEs separation. This work will provide referential significance in tunable MOFs development and actual applications of PAEs removal. [ABSTRACT FROM AUTHOR]

[Display omitted] • "Pre-embedded seed then growth" ensures the stability of the adsorbent structure. • Co-doping of dual-functional components exhibits effective synergistic adsorption. • Theoretical calculations of ligand exchange and hydrogen bonding mechanisms. • Adsorbents that degrade after adsorbing phosphates have fertilizer effect. • Proposing a closed-loop design from waste utilization to treatment and final reuse. Recovering and reusing of phosphorus (P) in wastewater is the optimal solution to address mineral shortages and eutrophication. Here, the layered double hydroxides (LDHs) grown on wood-derived aerogels (WAs) were prepared after screening the powdered precursors and named La/MgFe-LDH(LS)@WAs. The intricate pore structure and surface morphology of the WAs formed a fibrous network with ultra-low density, good strength and elasticity, allowing for uniform loading. The sample exhibited excellent adsorption capacity of 139.5 mg P/g at pH 4.0, and over 100.0 mg P/g within a wide pH range (3.0–8.0). Thomas and Yoon-Nelson models could effectively describe the dynamic adsorption process. Microscopic morphology and textural characteristics of the samples were characterized and molecular dynamics (MD) simulations and theoretical calculations based on density functional theory (DFT) were used to study the interaction mechanisms. The coordination bonds and weak interactions between the active component LS and La(OH) 3 with phosphates were characterized using interaction region indicator (IRI) and independent gradient model based on Hirshfeld molecular density partitioning (IGMH) methods. The atomic δg index mapped to the molecular structure vividly illustrated the maximum contribution of hydroxyl hydrogen to phosphate deprotonation oxygen in inter-fragment interactions on LS. Combining the formation of Me-O-P bonds characterized by X-ray photoelectron spectroscopy (XPS), the mechanism involves weak interactions (hydrogen bond) and chemical adsorption via ligand exchange. High removal efficiency was demonstrated in real wastewater. A method for waste reuse was also proposed. Plant cultivation experiments showed that La/MgFe-LDH(LS)@WAs could sustain wheat growth with slowly degrade and maintain high phosphate availability. The composite shows potential for water restoration, waste treatment, and value-added conversion in the production of controlled-release fertilizers. [ABSTRACT FROM AUTHOR]

In a water solution and with a low reaction temperature of 85 °C, the green preparation of lanthanum-modulated MOF-808 (Zr) was realized, the obtained La-MOF-808 have smaller grain size, larger specific surface area, higher pore volume and larger average pore diameter. When the molar ratio of La: Zr=1:1, 1L-MOF-808 had the best fluoride ion removal performance, and its maximum adsorption capacity for F- reached 101.4 mg/g, which was higher than that of the unmodulated MOF-808 and some other reported fluorine adsorbents. Meanwhile, the regeneration experiment demonstrated that even after five cycles, 1L-MOF-808 retained 73.8 % of its initial adsorption capacity, highlighting its commendable reusability. In addition, when 1L-MOF-808 was applied to actual fluorine-containing wastewater, with the fluoride ion concentration of 25.3 mg/L and an adsorbent dosage of 0.6 g/L, 1L-MOF-808 exhibited excellent resistance to anionic interference (SO 4 2-, Cl-), the concentration of fluoride ions in effluent was lower than 10 mg/L, meeting the stipulations of fluoride ion discharge outlined in GB39371–2020. Further adsorption mechanism investigation revealed that 1L-MOF-808's affinity for F- was attributed to electrostatic interaction and ligand exchange. Overall, the as-synthesized 1L-MOF-808 not only presents an environmentally friendly approach to producing MOF materials without organic solvents but also develops a new strategy for the design of high-performance adsorbent for effectively removing fluoride ions from wastewater. [Display omitted] • La-modulated MOF-808(Zr) was prepared for the first time and used to remove F-. • The adsorption mechanism involved electrostatic interaction and ligand exchange. • The maximum adsorption of 1LMOF-808 for F- was 101.4 mg/g. • La modulating provided additional active sites and improved the adsorption effect. [ABSTRACT FROM AUTHOR]

• A redesigned and novel two-chamber electrodeposition-electrodialysis combination craft was adopted. • The efficient recovery of Ni2+ and the synchronous removal of HPO 3 2- from spent bath was achieved in simple and rapid one-step purification. • The influence of current density, operation time, pH, dilution multiple, flow rate, and electrolyte concentration on craft performance were investigated. With the continuous promotion and application of electroless nickel plating technology, the environmental pollution caused by heavy metals nickel and phosphorus in the spent bath becomes more serious. It is challenging to develop a method for the treatment of a spent electroless nickel plating bath with the high-efficiency recovery of Ni2+ and synchronous removal of HPO 3 2-, no secondary pollution, and low energy consumption. Herein, a means that absolutely incorporates the ascendancy of two single treatment methods, called a combination of electrodialysis and electrodeposition, was used to treat the spent electroless nickel plating bath. The effects of current density, operation time, pH value of the spent bath, dilution multiple, flow rate, and electrolyte (Na 2 SO 4) concentration on the recovery, removal rate, and energy consumption were investigated. Then, the reusability of the ion-exchange membrane was studied. The experimental results indicated that the recovery of Ni2+ was 82.34%, the removal of HPO 3 2- was 51.61%, the energy consumption of this method was only 18.28 Wh/kg, and the stability of the anion exchange membrane was desirable. Overall, the study of this combined process provides a basis for the one-step treatment of spent electroless nickel plating bath by a comprehensive method and an idea for engineering the application of handling spent bath. [ABSTRACT FROM AUTHOR]

[Display omitted] • Designed a fluorescent probe to detect 1-hydroxyethane-1,1-diphosphonic acid. • Explored the optimum conditions for detection. • Researched the fluorescence quenching mechanism in detail. Organic phosphonates are widely used as scale inhibitors and metal ion chelators in industrial water treatment. 1-hydroxyethane-1,1-diphosphonic acid (HEDP) is one of the application of extensive organic phosphonates. However, due to physical and chemical properties, the detection process is extremely complicated. In this work, a fluorescent probe was prepared to detect HEDP which used salicylic acid (SA) and ferric ion (Fe3+) as sources for the first time. As far as optical properties were concerned, Fe3+-salicylic acid complex (Fe-SA) designed as fluorescent probe was significantly different from SA. The detection limit of HEDP was 2.7 μM (0.56 mg/L) under the optimal experimental conditions. The fluorescence quenching of SA can be attributed to static quenching.. [ABSTRACT FROM AUTHOR]

This work reports the synthesis of a novel 3D porous graphene (PG) from maleic acid (HO 2 CCH=CHCO 2 H) used as a carbon source through a simple one-step carbonization process. The sodium carbonate (Na 2 CO 3) was used as the skeletal substrate for 3D PG preparation and we observed that the ideal mass ratio of maleic acid (MA) to Na 2 CO 3 is 1:4, which gives the highest yield and net carbon content for 3D PG preparation. The Na 2 CO 3 decomposition temperature is greater than 550 °C which causes the release of CO 2 and hence ultimately it produced 3D porous graphene (PG). The prepared 3D PG was characterized by X-Ray Diffraction (XRD), Raman Spectra, Transmission Electron Microscope (HRTEM), Scanning Electron Microscope (SEM), X-Ray Photoelectron Spectroscopy (XPS), and Brunauer Emmett Teller (BET) Surface area. The synthesized 3D architectural frameworks of graphene offered well-defined pores with a large surface area amounting to 567.56 cm2g-1. However, with increasing temperature above 700 °C, there is a decrease in surface area which can be attributed to the heat shrinkage and sintering or collapse of smaller diameter pores. Also at higher temperatures, Na 2 CO 3 decomposes quickly which impart less effect on the morphology of synthesized graphene. In addition, electrochemical and adsorptive properties were also studied and a comparison is made with 3D rGO synthesized separately. The unique porous structure of 3D PG showed an excellent adsorption capacity of 433.3 (mg g-1) towards emerging pharmaceutical compound Atenolol and it further increases up to 642.4 (mg g-1) towards organic dye Rhodamine B, which is much higher than the 3D reduced graphene oxide rGO obtained by the chemical reduction process. Similarly, the as-synthesized 3D PG depicted enhanced oxidation and reduction properties as compared to 3D rGO as is evident from sharp anodic and cathodic peaks for the 3D PG prepared at 700 °C. [ABSTRACT FROM AUTHOR]

In this work, a novel adsorbent, 3D hierarchical CS@PANI@ZnAl-LDH composite, has been successfully fabricated through the hydrothermal synthesis of the carbon sphere, oxidative polymerization of polyaniline, and in-site growth of ZnAl-layered double hydroxides, simultaneously applied for the naproxen removal from aqueous solutions. The dynamics and isotherms fit better with the pseudo-second-order and Langmuir model, demonstrating the chemisorption, monolayer, and endothermic process. In addition, the high uptake capacities of CS@PANI@ZnAl-LDH for naproxen was 545.5 mg/g at 298 K when the pH was 5.0, outperforming most previously reported materials. Moreover, after five adsorption-desorption cycles, the spent CS@PANI@ZnAl-LDH maintains high removal efficiency and structural composition, revealing excellent recyclability and stability. Furthermore, Fourier transformed infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) analyses indicate electrostatic interactions, π-π interactions, and hydrogen bonding between CS@APNI@ZnAl-LDH and naproxen. Quantitative analyses, Localized orbit locator (LOL)-π isosurface, and Independent Gradient Model further verify the adsorption mechanisms mentioned above, indicating the synergistic effects between PANI and ZnAl-LDH improve the elimination ability for naproxen. Significantly, Hirshfeld surface analyses reveal that naproxen behaves as the H-bond acceptor, and the ZnAl-LDH acts as the H-bond donor. This work provided a feasible way to design purification materials for wastewater treatment. [Display omitted] • 3D hierarchical CS@PANI@ZnAl-LDH composite was synthesized and characterized. • The maximum adsorption capacity of CS@PANI@ZnAl-LDH was 545.54 mg/g for naproxen. • Experimental analyses and theoretical calculations reveal the adsorption mechanisms. • Hirshfeld surface analyses explain the donor-acceptor relationship in hydrogen bonds. • Naproxen behaves as the H-bond acceptor and the ZnAl-LDH acts as the H-bond donor. [ABSTRACT FROM AUTHOR]

• A novel ratiometric imprinted fluorescence sensor N -CDs@Eu-MOF@MIP was constructed. • Eu-MOF were introduced and enhanced the response sensitivity. • The dual emission strategy endowed sensors remarkable fluorescence color changes. • The fluorescence sensor selectively recognized malathion. • Smartphone-assisted platform offered a promising tool for visual inspection. Sensitive and rapid detection of pesticide residues in food is essential for human safety. A ratiometric imprinted fluorescence sensor N -CDs@Eu-MOF@MIP (BR@MIP) was constructed to sensitively detect malathion (Mal). Europium-based metal organic frameworks (Eu-MOF) were used as supporters to improve the sensitivity of the BR@MIP. N -doped carbon dots (N -CDs) were used as fluorescent source to produce fluorescent signal. A linear relationship between the concentration of Mal and the fluorescence response of the sensor was found in the Mal concentration range of 1–10 μM with a limit of detection (LOD) of 0.05 μM. Furthermore, the sensor was successfully applied for the detection of Mal in lettuce, tap water, and soil samples, with recoveries in the range of 93.0 % − 99.3 %. Additionally, smartphone-based sensors were used to detect Mal in simulated real samples. Thus, the construction of ratiometric imprinted fluorescence sensor has provided a good strategy for the detection of Mal. [ABSTRACT FROM AUTHOR]

[Display omitted] • A II-type BiVO 4 /BiOBr heterojunction was prepared by anion exchange method. • The mechanism of II-scheme photocatalysis was explained. • Photocatalysis and PMS activation synergistically promote the degradation of enrofloxacin. • The presence of PMS induces a transformation of the primary active species. • O 2 − and 1O 2 are the prominent radicals for ENR degradation. Compared with the pure photocatalytic degradation system, although the sulfate radicals ( S O 4 · -) generated in the peroxymonosulfate-assisted photocatalytic (PMS-photo) system redound to improve degradation activity. However, the degradation mechanism of the PMS-photo system still needs to be improved. For example, the relationship between superoxide radical (O 2 −) generation and PMS has been overlooked. Herein, the BiVO 4 /BiOBr photocatalyst was prepared via anion exchange method. Subsequently, the in-situ growth of BiVO 4 on the surface of BiOBr nanosheet was confirmed though various characterization techniques. The degradation performance of the PMS-photo system was investigated, in which the 10 wt% BiVO 4 /BiOBr (BVB) composite exhibited the highest efficiency in degrading enrofloxacin (ENR, 95 %, 90 min) and tetracycline (TC, 94 %, 20 min) under visible light. Moreover, the structure of the intermediate product and the corresponding toxicity were determined by liquid chromatography-mass spectrometry (LC-MS) and Toxicity Estimation Software (T.E.S.T). Photoelectrochemical and fluorescence detection were employed to reveal that 10 wt% BVB has the fastest photogenerated carrier generation, separation and transmission efficiency. In addition, results from radicals quenching experiments, electron paramagnetic resonance (EPR), energy band structure analysis and DFT calculation were combined to substantiate the formation of II-type heterojunction between BiVO 4 and BiOBr. More importantly, based on the above results, it was confirmed that the active species in the pure photocatalytic system were holes (h+) and electrons (e−). Due to the introduction of PMS, O 2 − and singlet oxygen (1O 2) were generated, thereby achieving efficient degradation of pollutants. This result revealed the effect of peroxymonosulfate on the generation of O 2 −, presented a new perspective on the synergy of PMS with photocatalysis and offered a novel avenue for enhancing the performance of underperforming photocatalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • A facile dual physico-chemical activation strategy is proposed. • The synthesized NPHPC possesses high specific surface area, pore volume, specific capacitance and excellent hydrophilicity. • The NPHPC delivered a splendid desalination capacity and good cycling stability. The preparation of heteroatom-doped hierarchical porous carbons (HPCs) possessing both high-performance and cost-effective is advantageous for the advancement of capacitive deionization (CDI). Biomass, which is abundant and inexpensive, has been widely utilized as a precursor for carbon electrodes. However, the simple pyrolysis of a single biomass typically leads to insufficient porosity with narrow surface area, along with poor wettability and conductivity, thereby resulting in limited desalination performance. Therefore, we employ ammonium dihydrogen phosphate (NH 4 H 2 PO 4) and potassium carbonate (K 2 CO 3) as chemical and physical activators, respectively, to co-activate lotus petiole (LP) for the preparation of N/P co-doped hierarchical porous carbon (NPHPC). In comparison with conventional single K 2 CO 3 activation, NPHPC prepared through dual physico-chemical activation exhibits exceptional specific surface area (S BET , 2170.00 m2/g), excellent pore volume (V pore , 1.16 cm3/g), outstanding mesoporosity (V meso /V pore , 72.41 %), superior hydrophilic performance (contact angle: 39°), high specific capacitance (221.86F/g), moderate N-doping (3.1 %) and P-doping (0.4 %). When assembled for desalination, the synthesized materials demonstrate a fabulous electroadsorption capacity of 21.85 mg/g together with notable cycling stability, highlighting their excellent application prospects. In summary, this work presents innovative ideas in proposing a facile synthesis of high-performance heteroatom-doped HPCs for CDI desalination. [ABSTRACT FROM AUTHOR]

Highly efficient multifunctional adsorbent successfully realizes the removal of Cr ions from wastewater. The adsorbent is easily separated from the water to avoid secondary pollution. [Display omitted] • A novel 3D multifunctional composite magnetic adsorbent material has been successfully synthesized and applied for the removal of Cr(VI) from solution. • The composite adsorbent enables efficient capture and reduction of Cr(VI) under full light exclusion conditions. • The exceptional recyclability mitigates the issue of secondary contamination from the adsorbent. Designing a magnetic adsorbent material that is both reducible and has strong adsorption properties is significant in reducing Cr(VI) ion pollution. Herein, a 3D multifunctional composite adsorbent for Cr(VI) ions was obtained by using Fe 3 O 4 surface-arrayed magnesium iron layered double hydroxides (Mg/Fe-LDH) micro sheets as a substrate with in situ growth of Cu 2 O nanoparticles (Cu 2 O NPs) on their surfaces. Under dark conditions, adsorption capacity of the Cu 2 O@LDH@Fe 3 O 4 for Cr(VI) was up to 218.82 mg·g−1, surpassing that of Cu 2 O, Mg/Fe-LDH@Fe 3 O 4 , and Mg/Fe-LDH by factors of 1.39, 4.41, and 8.32 respectively. Surprisingly, the removal of Cr(VI) was as high as 76.16 % by the Cu 2 O@LDH@Fe 3 O 4 (C initial = 200 mg/L, pH = 3). Kinetic, isotherm, and thermodynamic results reveal that the removal of Cr(VI) by the Cu 2 O@LDH@Fe 3 O 4 is consistent with the pseudo-second-order kinetic model of spontaneous monomolecular layer chemisorption. Density functional theory (DFT) calculations show that HCrO 4 - has a lower energy band gap and is more easily reduced by Cu 2 O. Therefore, the reason for the adsorbent having more removal effect under acidic conditions was revealed. The XPS and FT-IR experimental mechanism analysis results indicated that Cr(VI) is immobilized on the Cu 2 O@LDH@Fe 3 O 4 surface through electrostatic interactions, followed by reduction to Cr(III) by Cu 2 O NPs, which is subsequently adsorbed on the surface of the Cu 2 O@LDH@Fe 3 O 4. This novel adsorbent structure and unique Cr(VI) removal mechanism provide new ideas for the design of future adsorbents. [ABSTRACT FROM AUTHOR]

[Display omitted] Effective removal of antibiotics in the environment can be a demanding issue concerning the ecosystem and human health. Photocatalysis and peroxymonosulfate (PMS) oxidation have become important methods to effectively remove stubborn pollutants. In this work, by integrating these two technologies, an efficient system for degrading chloramphenicol (CAP) in water was proposed. The system was constructed by coupling strontium-doped lanthanum cobaltate (LSCO5) with chlorine-doped carbon nitride (CGCN). By doping, the increase of oxygen vacancy and the adjustment of bandgap were realized. Photoluminescence and electrochemical impedance experiments showed that the heterojunction can promote electron transfer and photogenerated carrier separation. Under the synergistic effect of PMS oxidation and photocatalysis, the prepared composite with an optimal loading of 40% LSCO5 can degrade 95.6% of CAP within 20 min. Degradation experiments on different pollutants proved the versatility of the catalytic system. The enhanced degradation mechanism of CAP was explored based on the assessment of the degradation efficiency of CAP, electron paramagnetic resonance (EPR), and quenching experiments. Through liquid chromatography-mass spectrometry (LC-MS) analysis, a possible route for CAP degradation was also proposed. This research provides some inspiration for the remediation of polluted water with perovskite-based catalyst under the synergistic effect of PMS and photocatalysis. [ABSTRACT FROM AUTHOR]

The release of benzothiazoles into the environment has been reported to affect the ecological environment and human health, so it makes significant sense to remove benzothiazoles from aquatic environment. They are poorly eliminated by conventional wastewater treatment. A few studies have shown that benzothiazoles are difficult to bioaccumulate or sorb to particles, therefore, it is very meaningful to study their efficient adsorption. In this work, the novel combined modified montmorillonite with hydroxyl iron pillared and cationic panthenol intercalation (Fe-CPMMt) was firstly prepared and evaluated its removal effect for emerging contaminant-benzothiazole. The batch adsorption experiments showed that the maximum adsorption capacity of Fe-CPMMt for benzothiazole was 69.72 mg/g, while that of the original acidified sodium montmorillonite, alone hydroxyl iron pillared montmorillonite (Fe-AMt), alone cationic panthenol intercalated montmorillonite were 11.39 mg/g, 43.68 mg/g and 38.18 mg/g, respectively. The adsorption process for benzothiazole on Fe-CPMMt-1.0 conformed well to Langmuir isotherm adsorption model and the pseudo-second-order kinetic model, and was spontaneous and endothermic. Moreover, combining with the Zeta potential values of Fe-AMt and Fe-CPMMt-1.0, and with the help of Multiwfn wave function program based on density functional theory, the electrostatic attraction and coordination between Fe-AMt and benzothiazole, while the electrostatic interaction, hydrophobic partitioning, complexation, p-π/π, OH/π and CH/π interactions were verified between Fe-CPMMt and benzothiazole pollutant. The work confirmed that the novel combined modified montmorillonite with hydroxyl iron pillared and cationic panthenol intercalation has a better adsorption effect on benzothiazole. Combined with the insight into the adsorption mechanism from the atomic level, it might provide novel information for exploring a new more efficient inorganic-organic combined modified montmorillonite adsorbent for removing stubborn organic contaminants in water. [Display omitted] [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries are widely regarded as the most promising batteries for the future due to their higher specific capacity and lower prices. Various strategies are utilized to alleviate the shortcomings of Li–S batteries failing to reach theoretical capacity. However, basic research at the molecular level continues to be lacking. Therefore, we use molecular dynamics to study the details of the solvated structure of Li–S batteries electrolyte and the nature of the transport process, revealing the relationship between the solvated structure of the electrolyte of LiPF6 and the organic solvent ethylene carbonate/dimethyl carbonate (EC/DMC). The electrolyte of Li2S4 was first simulated in a pure solvent environment. Then the LiPF6 salt was added to the model to simulate a typical electrolyte for a working Li–S battery. Regarding the rationality of the solvent system, various reference systems such as density, dielectric constant, viscosity and diffusion coefficient of the solvent were used for verification. And the detailed composition of the first solvation shell of the polysulfate ion and the coordination number of the ions are discussed. These results provide new insights into the use of EC/DMC electrolytes in Li–S batteries, while at the same time providing a basis for efficient future predictions of electrolyte structure and transport in complex electrode confinements. The radius of the first solvation shell of each component is the PF 6 − anion at about 0.22–0.28 nm, the DMC solvent at about 0.32–0.36 nm and the EC solvent at about 0.41 nm, respectively. The first solvation shell according to these distributions has a radius of about 0.5 nm. The coordination number in the first solvation shell is plotted, which is about 1.88 for PF 6 − , 1.86 for DMC, and about 0.14 for EC. In conclusion, 3.88 molecules are produced in the first solvation shell of the ion. [ABSTRACT FROM AUTHOR]

In recent years, metal-organic framework derivatives have been regarded as materials with great potential for water treatment applications. In this study, we employed a polyvinylpyrrolidone (PVP)-assisted copper-cobalt bimetallic zeolitic imidazole framework (ZIF) as a template to rationally design nanosheet-like mixed metal oxide embedded nitrogen-doped carbon (CuCoO-PC). CuCoO-PC exhibited excellent degradation potential towards metronidazole (MNZ) and achieved almost complete degradation within 7 min through the activation of peroxymonosulfate (PMS). Importantly, the introduction of copper into CuCoO-PC established strong interactions between copper and cobalt, accelerating the activation performance of PMS. Furthermore, PVP, rich in nitrogen atoms, formed strong coordination interactions with ZIF precursors, which effectively protected the morphological stability of ZIF at high temperature, preventing collapse and aggregation. Meanwhile, the formation of nitrogen-doped carbon networks provides a pathway for the generation of non-radical. The study found that CuCoO-PC continuously activated PMS, generating various reactive oxygen species (ROS), among which SO 4 •- and 1O 2 played decisive roles. By calculating the HOMO, LUMO, and Fukui functions, we identified the reactive sites of MNZ and proposed possible degradation pathways. CuCoO-PC demonstrated excellent catalytic performance, reduced toxicity of intermediate products, and good reusability, all of which highlight its enormous potential in practical applications. [Display omitted] • CuCoO-PC composites are prepared using PVP to enrich the nitrogen content. • CuCoO-PC/PMS system exhibits prominent catalytic performance for MNZ removal. • SO 4 •- and 1O 2 was the main active substance involved in the MNZ degradation. • CuCoO-PC was stable and effective in multiple cycles of MNZ degradation efficiency. • The most reactive site on MNZ molecule was predicted by DFT calculation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Green activation-self-activation strategy was proposed to prepare GO-inbuilt ENHPCs. • The splendid SAC of 17.86 mg/g and rapid ASAR of 0.99 mg/g/min for Ni2+ were gained. • The potential for eliminating NaCl, MgCl 2 , CaCl 2 and Ni2+ wastewater was evaluated. • Micro-mesoporous structure and copious active sites accelerated ion removal. Capacitive deionization (CDI) is considered a polar-promising technology to remove heavy-metal ions from wastewater. Herein, a green activation-self-activation strategy was exploited to build graphene (GO)-inbuilt mesopore-dominated N-doped hierarchical porous carbons (ENHPCs) using sodium lignosulfonate (SLS) as carbon sources/self-activators. Different from SLS self-activation and K 2 C 2 O 4 -SLS activation-self-activation, ENHPC LKG gained via GO-mediated K 2 C 2 O 4 -SLS activation-self-activation showed suitable mesopore-dominated micro-mesoporous structures with high surface area of 1795.5 m2/g, large mesoporous volume of 0.87 m3/g, 3.65 % N-doping and excellent conductivity. Its unique hierarchical porous structure and abundant active sites facilitated the ion rapid insertion and extraction. When utilized to capture low-concentration nickel (Ni2+) ions, ENHPC LKG delivered splendid salt removal capacity of 17.86 mg/g, rapid average salt removal rate of 0.99 mg/g/min and standout cycle stability. Meanwhile, ENHPC LKG was further extended to remove NaCl, MgCl 2 , CaCl 2 and Ni-containing wastewater, showing superior CDI property. Moreover, the recycled ENHPC LKG (10th) taken to eliminate indomethacin (IDM) depicted a splendid adsorption capacity. This work proved the significant applicant potential of the novel and green ENHPC LKG for disposing of Ni2+ ions via CDI technology. [ABSTRACT FROM AUTHOR]

[Display omitted] • The prepared Tb-MOF emits stable Tb characteristic fluorescence at 545 nm in water. • The prepared Tb-MOF can be easily recycled after the OTC detection. • Based on the fluorescence detection of OTC by Tb-MOF, a test paper that can be easily carried, monitored in real time and has a clear color change was prepared. • Tb-MOF performed excellent in detecting the concentration of OTC in actual water samples. Oxytetracycline hydrochloride (OTC) is a commonly used over-the-counter antibiotic, valued for its potent antibacterial properties. However, the inappropriate and excessive use of OTC can result in the accumulation of the drug in both the environment and human body, causing significant harm to ecosystems and human health. Therefore, the development of a fast and sensitive method for detecting OTC is of great significance. Lanthanide metal–organic frameworks (LnMOFs) can effectively excite lanthanide metals to emit long-lifetime, narrow and stable fluorescence based on the antenna effect, but their application in fluorescence sensing is rarely reported. In this work, a strongly fluorescent material Tb-MOF was synthesized by a facile solvothermal method using 1,2,4,5-phenylenetetracarboxylic acid (H 4 btec) and 1,10-phenanthroline (1,10-phen) as organic ligands and lanthanide metal Tb as the luminescent center. Tb-MOF is a stable material in water and shows excellent linearity with OTC in the concentration range of 0 ∼ 70 μM, with low detection limit (0.12 μM) and luminescence color transition from bright green to dark green during the detection process. X-ray diffraction, UV–vis absorption and fluorescence lifetime analyses revealed that the fluorescence quenching of Tb-MOF by OTC is caused by the inner filter effect in static quenching. Test strips for OTC detection were successfully prepared using Tb-MOF. These strips are not only low cost and easy to prepare but can also be used as portable sensing devices that can be easily distinguished by the naked eye during OTC testing. This study not only presents a fluorescent probe for the detection of OTC in water but also offers a practical method for converting fluorescent luminescent materials into functional devices for OTC detection. [ABSTRACT FROM AUTHOR]

[Display omitted] • Composition of dual-emitting fluorescent probes was achieved by utilizing Eu and Tb as bimetallic centers. • First proposed dual-emission ratio sensor constructed with diaminoterephthalic acid. • Emission color conversion by adjusting the doping ratio of Eu and Tb. • The probe enables ratiometric sensing of furacilin and has excellent sensitivity and low detection limits. Lanthanide metal–organic frameworks (LnMOFs) have substantial potential in luminescence due to their unique antenna effect. Nevertheless, the single emission is susceptible to pseudo-signals caused by external environmental conditions, which significantly threaten the accurate measurement of the concentration. In this case, we prepared a dual-emission fluorescent probe {Eu x Tb 1-x (NH 2 -BDC) 3 (DMF) 4 ·2DMF} ∞ (NH 2 -BDC = Diaminoterephthalic acid, DMF = N , N -dimethylformamide). The stable dual-emission signal provides a superior signal output for detecting nitrofurazone (NFZ), which is detected by the probe with excellent fluorescence for 0–10 μM NFZ. In the investigation of the detection mechanism, it is speculated that NFZ incorporates with probe to generate a novel complex. Furthermore, The UV absorption curves of the novel complexes and NFZ overlap extensively with those of the probe. The addition of NFZ attenuates the characteristic luminescence of Eu and Tb by competing for the absorption of the excitation light of the probe. The probe has exhibits rapid response, excellent sensitivity, visual detection and a meagre detection limit (LOD = 0.013 μ M) for the detection of NFZ. This work not only broadens the application of LnMOFs in the field of ratiometric detection but also provides a favorable fluorescent probe for the quantitative detection of NFZ. [ABSTRACT FROM AUTHOR]

Rapid and real-time detection of 2, 4, 6-trinitrophenol (TNP) is of great importance for the living environment and human health. Herein, we constructed an innovative ratiometric fluorescence imprinted sensor with fast response and high selectivity based on magnesium and nitrogen co-doped carbon dots (Mg, N-CDs) and chromium telluride quantum dots (r-CdTe) self-assembled in zirconium-based metal organic frameworks (UiO-66) combined with imprinted polymers for the detection of TNP. In the protocol, the introduction of UiO-66 with large specific surface area and porosity using as carrier material significantly enhanced the mass transfer rate, which improved the sensitivity of the Mg, N-CDs/r-CdTe@UiO-66@MIP (LHU@MIP). And the Mg, N-CDs with high quantum yields and r-CdTe were selected as fluorescence emitting elements to yield fluorescence signal, achieving signal amplification. The dual-channel strategy enabled the sensor to not only display a fast fluorescence response, but also generate a dual-response signal under the action of internal filtering effect (IFE). Combining these advantages, the LHU@MIP had a wide linear range (1–100 μM), good detection sensitivity (0.56 μM), and a distinct color change (from blue to pink). Meanwhile, for accurate on-site analysis, we designed a portable smart sensing platform with a color recognizer application. The smartphone enabled visual sensing of TNP by capturing fluorescent images and converting them into digital values. More importantly, the platform was successfully utilized for the analysis of TNP in the simulated actual samples with considerable results. Therefore, the developed platform was characterized by low cost, portability, ideal specificity, and provided a strategy for on-site monitoring of TNP. [Display omitted] • A fluorescence imprinted sensor based on LHU@MIP for TNP was designed. • Porous UiO-66 was introduced to enhance the mass transfer rate and sensitivity. • Smartphone-assisted platforms offer promising tool for visual detection of TNP. • The platform was applied to the simulated real-sample with satisfactory results. [ABSTRACT FROM AUTHOR]

Biologically treated coking wastewater (BTCW) frequently contains many kinds of refractory and toxic organic pollutants, which is far from meeting the discharge standard of GB16171–2012. In the present work, the peroxymonosulfate (PMS) activation processes via Cu-doped LaFeO 3 (LFC) prepared with Bis (hexamethylene triaminepenta(methylenephosphonic acid) (BHMTMP) as the complexing agent was first utilized to degrade BTCW. The degradation reaction rate constant (k obs) of LaFe 0.5 Cu 0.5 O 3 (LFC5)/PMS for COD Cr and NH 3 -N was 3.65 times and 3.63 times for LFO (LaFeO 3)/PMS. Moreover, the k obs of LFC5/PMS system prepared using BHMTMP as the complexing agent surpassed that of the LFCC/PMS system prepared with citric acid (CA) as the complexing agent, and the former was 2.3 times and 1.8 times greater than that of the latter for the removal of COD Cr and NH 3 -N, respectively. The leaching of Cu and Fe of LFC5 was much less than that of LFCC, the strong chelation performance of BHMTMP with various metal ions can greatly reduce the leaching of metal ions and improve the stability of the catalyst. Hydroxyl radicals, sulfate radicals, and singlet oxygen were generated in the LFC5/PMS system, with singlet oxygen playing a dominant role. HPLC, UV absorption spectra, and 3D-EEM fluorescence spectra were used to analyze pollutant components in BTCW before and after degradation, demonstrating the effective removal of certain residual contaminants. In addition, the degradation process of BTCW was modeled using a 3-factor-3-level Response Surface Methodology (RSM) model. RSM model fitted the true experimental results well. This research offers a new approach for the comprehensive treatment of BTCW to meet standard discharge requirements and promote a more cost-effective operating process. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Au@CeO 2 @Pt nanoenzymes exhibited an outstanding peroxidase-like activity. • A colorimetric-fluorescent dual-mode assay for SARS-CoV-2 was constructed. • The immunosensor achieved detection in simulated samples with satisfactory results. Developing powerful alternatives to natural enzymes has been a target pursued by researchers, and nanozymes are considered to be the best candidate due to their unique advantages of high stability, high activity, and easy modification. In this study, the multishell complexes of Au@CeO 2 @Pt nanozymes were successfully synthesized which exhibited an excellent intrinsic peroxidase-like ability to oxidize 3,3′,5,5′-tetramethylbenzidine (TMB), and resulting in a visible colorimetric signal. Interestingly, due to the internal filtration effect, the blue-emitting oxidized TMB (oxTMB) can also quench the red-emitting light from bimetallic AuAg nanoclusters. Based on the above properties, a kind of robust immunoassay for target protein detection was established. The dual-mode immunoassay is more accurate for SARS-CoV-2 detection on account of the reciprocal corroboration of the signals. More importantly, the immunoassay had high sensitivity with a low limit of detection and excellent recovery rates in simulated urine/saliva samples. Therefore, it is highly anticipated the immunoassay based on the newly developed nanozyme became an accurate instrument for diagnosing SARS-CoV-2 in the biomedical field. [ABSTRACT FROM AUTHOR]

Mg/Al layered double hydroxides (LDH) intercalated by Ethylenediamine-tetramethylene phosphonic acid (EDTMP) was synthesized to remove Pb2+ and Cd2+ from aqueous solutions, and the intercalation of EDTMP enhanced the adsorption capacity of LDH for both of the heavy metal ions. At a pH of 6.5 and with an optimal intercalation amount of 20% EDTMP, the 20EDT-LDH composite demonstrated an adsorption capacity of 249.82 mg/g for Pb2+ and 160.85 mg/g for Cd2+, resulting in a removal rate of 64.34% for Pb2+ and 99.93% for Cd2+. 20EDT-LDH showed great resistance to interference ions, as it maintained satisfying adsorption performance when a much higher concentration of K+ and Ca2+ than that of Pb2+ and Cd2+ were present, with the adsorption capacity of Pb2+ and Cd2+ being greater than 83.4% and 66.3% of the maximum adsorption capacity, respectively. This was due to the strong chelation ability of EDTMP with Pb2+ and Cd2+, as confirmed by characterizations after adsorption of 20EDT-LDH with Pb2+ and Cd2+. Moreover, the affinity between EDTMP and LDH was revealed via Independent Gradient Model based on the Hirshfeld partition of molecular density (IGMH) and Hirshfeld surface analysis. [Display omitted] • LDH with EDTMP was firstly prepared and separate Pb2+ and Cd2+. • The adsorption capacity of 20EDT-LDH greatly improved than that of LDH. • IGMH and Hirshfeld surface was executed to visualize the interaction. • The coordination mechanism between EDTMP and Pb2+ or Cd2+ was revealed. • The recycle of 20EDT-LDH was good. [ABSTRACT FROM AUTHOR]

[Display omitted] • N-doped La 2 CuO 4 had been synthesized using melamine as the N precursor. • N-doped La 2 CuO 4 showed enhanced catalytic activity and stability. • Density Functional Theory (DFT) calculations were performed to verify the results. • A mechanism of phenol degradation was proposed. • The toxicity of degradation intermediates was greatly reduced. Herein, N-doped perovskite La 2 CuO 4 (LCO) (N-LCO(M)) was fabricated by sol–gel rapid calcination method using melamine (M) as N source/ligand, and applied for the catalytic wet air oxidation (CWAO) to degrade high-concentration phenol-containing simulated wastewater. The experimental results exhibited that N-LCO(M) illustrated enhanced phenol degradation efficiency. Thereinto, 87.9% COD degradation efficiency was achieved in simulated wastewater containing 8000 mg/L phenol, while for undoped LCO prepared with citric acid (CA) as ligand (LCO(CA)) was only 43.8%. The systematic characterizations and density functional theory (DFT) calculations were utilized to verify the above results. The results revealed that N doping favored the formation of more oxygen vacancies (*) and facilitated the charge transfer between Cu and O. More oxygen vacancies (*) reinforced the ability of N-LCO(M) to adsorb O 2 to form reactive oxygen species (O*), and meanwhile, the charge transfer between Cu and O was manifested as the redox cycle of the catalytic active metal Cu2+/Cu1+. The redox cycle also promoted the formation of O 2 − and HO, making the more exhaustive degradation of phenol. This successfully proved that N doping was core to improving the activity and stability of N-LCO(M). Moreover, a possible mechanism of phenol degradation was proposed based on the experimental results and DFT calculations. Eventually, the toxicity of the intermediate products was further evaluated by quantitative structure–activity relationship (QSAR) analysis, showing the significantly reduced toxicity of the intermediate products. Overall, the proposed CWAO technique is a green and promising wastewater treatment method. [ABSTRACT FROM AUTHOR]

[Display omitted] • EDTMP was first used as a dopant to prepare organo-inorganic hybrid HAP. • The adsorption capacity of 20ED-HAP was more than 10 times that of HAP. • IGMH and Hirshfeld surface can vividly visualize the interaction of EDTMP/ HAP. • AIM and ELF was executed to reveal the coordination of EDTMP/ Zn2+ or Co2+. Hydroxyapatite (HAP) incorporated with ethylenediaminetetramethylene phosphonic acid (EDTMP) was prepared and used for the separation of the toxic Zn2+ and Co2+ heavy metal ions in an aqueous solution. When the doping amount of EDTMP was 20%, the adsorption capacity of 20ED-HAP composite for Zn2+ and Co2+ reached 229.5 mg/g and 162.4 mg/g, which was 11.0 times and 11.8 times that of synthesized HAP in the absence of EDTMP. The effects of different concentrations of common coexisting ions such as Na+, K+, Ca2+, and Mg2+ were explored, and the removal rate of Co2+ or Zn2+ in a simulated actual water environment was also investigated. The removal of cobalt ions by EDTMP-HAP complex included ion exchange and surface complexation mechanisms. In addition to the above two mechanisms, the separation of zinc ions involved the dissolution precipitation mechanism with the formation of CaZn 2 (PO 4) 2 ·2H 2 O. Moreover, the affinity between EDTMP and HAP was revealed via Independent Gradient Model based on the Hirshfeld partition of molecular density (IGMH) and Hirshfeld surface analysis. Meanwhile, the interaction mechanism between EDTMP and Co2+ or Zn2+ was explored in depth through Multiwfn wavefunction analysis. The prepared adsorbent could be used as a low-cost potential adsorbent for toxic Zn2+ and Co2+ ions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nitrate-mediated organic salt activation strategy was proposed to fabricate high-yield-high-performance NHPC. • Tertiary porous structure and surface-exposed active sites facilitated salt ion removal. • The splendid desalination capability and rapid desalination kinetics were acquired. • The universality and commerciality for NHPCX y were further investigated. Developing a green and facile strategy for high-yield preparing N-doped hierarchical porous carbon (NHPC) for capacitive deionization (CDI) is a huge challenge for desalination. So far, there are limited reports on high-yield NHPC synthesis. Herein, a novel nitrate (NaNO 3 , KNO 3 , Zn(NO 3) 2 and NH 4 NO 3)-mediated-organic salt activation strategy was exploited to construct NHPCX y (X = Na, K, Zn, NH 4 ; Y(nitrate ratio) = 1, 3, 5). Thereinto, C 6 H 5 K 3 O 7 served as activator and nitrate acted as assisted-activator and foaming agent. Compared with C 6 H 5 K 3 O 7 activation, NHPCNa 3 acquired by NaNO 3 -C 6 H 5 K 3 O 7 co-activation achieved 35.5% high yield and depicted 3D macroarray structures with high specific surface area (S BET) of 1912.2 m2/g, large pore volume (V pore) of 1.56 cm3/g and 1.21 % N content. Its tertiary pore structure and rich surface-exposed active sites favored the ions rapid insertion and extraction from the micropores. The final NHPCNa 3 delivered an excellent salt adsorption capacity (SAC) of 19.74 mg/g. Moreover, it exhibited 14.61 mg/g high SAC at 15.5 mg/cm2 and only showed 9.4% SAC drop after 50 cycles. While using diverse biomass precursors, it obtained an optimal SAC of 23.16 mg/g. NHPCK 3 , NHPCZn 3 and NHPC(NH 4) 3 also presented the feature of high-yield-high-performance. The high yield came from the foaming effect of nitrate and the property difference may be ascribed to the different cations. This work provides one span-new green universality strategy to design high-yield-high-performance NHPCs in commercial-grade CDI applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • A composite PMS activator of S-doped g-C 3 N 4 /NiCo 2 O 4 was obtained. • S doping widens the difference in the work functions of CNS and NCO. • Enhanced BIEF promotes the directional transfer of electrons from CNS to NCO. • 1O 2 was formed mainly through SO 4 •−, •OH and •O 2 − conversion. Transition metal oxide-mediated heterogeneous peroxymonosulfate (PMS) activation on organic pollutant degradation has attracted much attention, where continuous redox cycling between high and low valence metal ions is the key step as it relates to the radical generation. Herein, a composite PMS activator of S-doped g-C 3 N 4 /NiCo 2 O 4 (CNS_NCO) was constructed and exhibited excellent tetracycline (TC) degradation performance with 96.9% removal efficiency within 30 min. Experimental and theoretical calculations indicated that S doping not only widened the difference in the work function of CNS and NCO, but also enhanced the built-in electric field intensity of CNS_NCO heterojunctions, resulting in more electron transfer from CNS to NCO in a directional manner and accelerating the Co(III)/Co(II) and Ni(III)/Ni(II) redox cycle to form more reactive oxygen species (ROS). It was demonstrated that 1O 2 (main ROS) was formed mainly through SO 4 •−, •OH and •O 2 − (minor ROS) conversion. Meanwhile, high-valent cobalt-oxo (CoIV = O) species also played an important role in TC degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Magnetic HAP doped with HDTMP was firstly prepared and remove Sr2+ and Co2+. • The adsorption capacity of 10HD-MHAP was more than 5 times that of MHAP. • IGMH and Hirshfeld surface was executed to reveal the interaction. • The coordination mechanism between HDTMP and Sr2+ or Co2+ was visualized. • The immobilization of 10HD-MHAP to Sr2+ or Co2+ was excellent. The magnetic Hexamethylene diamine tetramethylene phosphonic acid (HDTMP)-hydroxyapatite nanoparticles (HD-MHAP) were firstly prepared and applied for the immobilization of radioactive Sr2+ (Strontium ion) and Co2+ (Cobalt ion). The molar ratio of organic phosphine in HDTMP to total phosphorus was 10% (10HD-MHAP) and can also be easily separated from aqueous solution. At the equilibrium concentration of Sr2+ and Co2+ (200 mg/L), the adsorption capacity of MHAP and 10HD-MHAP on Co2+ was 28.4 mg/g and 172.3 mg/g, respectively and for Sr2+, the adsorption capacity was 54.9 mg/g and 320.7 mg/g. Additionally, the desorption percentage of Sr2+ (%) and Co2+ (%) was very low, which was 0.66 and 1.61, respectively. This is significant because the irreversible adsorption of HDTMP/Fe 3 O 4 /HAP composite for Sr2+ and Co2+ ensures the captured radionuclides will not be released back into the aquatic systems. Moreover, the affinity between HDTMP and HAP and the coordination of HDTMP and Sr2+ or Co2+ was probed by Multiwfn wavefunction analysis. The results indicated that the formation of a ternary surface complex of MHAP-HDTMP-M (Sr2+ or Co2+) was the key to the excellent immobilization performance of HD-MHAP composite for Sr2+ or Co2+. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fluorescent quantitative detection of Cu2+ realized by L-cysteine modified ZnS. • The formation of ground state complexes is verified by experiments and simulations. • Fluorescence quenching mechanism of the probe by Cu2+ revealed by simulation. L-cysteine (L-Cys) capped ZnS fluorescent probe (L-ZnS) were synthesized by binding ZnS nanoparticles in situ with L-Cys, the fluorescence intensity of L-ZnS increased more than 3.5 times than that of ZnS due to the cleavage of S–H bonds and the formation of Zn–S bonds between the thiol group of L-Cys and ZnS. The addition of copper ions (Cu2+) can effectively quench the fluorescence of L-ZnS to realize the rapid detection of trace Cu2+. The L-ZnS showed high sensitivity and selectivity to Cu2+. The LOD (limit of detection) of Cu2+ was as low as 7.28 nM and linearity in the concentration range of 3.5–25.5 μM. Meanwhile, for the first time, electron localization function (ELF), bond order density (BOD), and natural adaptive orbital (NAdO) analysis in the Multiwfn wavefunction program based on density functional theory were carried out to probe the binding sites and binding mode of L-Cys with Cu2+, it indicated that the deprotonated carboxyl oxygen atoms of L-Cys had the lowest electrostatic potential (ESP) and provided lone pair electrons to coordinate with Cu2+ to form non-luminescent ground state complexes, which led to fluorescence quenching of L-ZnS. From the microscopic point of view of atoms, the mechanism of fluorescence enhancement of L-Cys capped ZnS and the mechanism of fluorescence quenching after adding Cu2+ were revealed in depth, the theoretical analysis results were accordance with the experiments. [ABSTRACT FROM AUTHOR]

[Display omitted] • A magnetic-assisted PEC immmunosensor was constructed to detect SARS-CoV-2 N protein. • Fe 3 O 4 @SiO 2 @Au/Ab 1 can extract targets in complex samples and simplify the process. • Active species were studied by free radical trapping assay and ESR test. • The mechanism of photogenerated e−/h+ of SiO 2 @TiO 2 @CdTe QDs transfer was deduced. • The immunosenor had a low detection limit of 1.8 pg mL−1. A sensitive, reliable, and cost-effective detection for SARS-CoV-2 was urgently needed due to the rapid spread of COVID-19. Here, a "signal-on" magnetic-assisted PEC immunosensor was constructed for the quantitative detection of SARS-CoV-2 nucleocapsid (N) protein based on Z-scheme heterojunction. Fe 3 O 4 @SiO 2 @Au was used to connect the capture antibody to act as a capture probe (Fe 3 O 4 @SiO 2 @Au/Ab 1). It can extract target analytes selectively in complex samples and multiple electrode rinsing and assembly steps were avoided effectively. CdTe QDs sensitized TiO 2 coated on the surface of SiO 2 spheres to form Z-scheme heterojunction (SiO 2 @TiO 2 @CdTe QDs), which broadened the optical absorption range and inhibited the quick recombination of photogenerated electron/hole of the composite. With fascinating photoelectric conversion performance, SiO 2 @TiO 2 @CdTe QDs were utilized as a signal label, thus further realizing signal amplification. The migration mechanism of photogenerated electrons was further deduced by active material quenching experiment and electron spin resonance (ESR) measurement. The elaborated immunosensor can detect SARS-CoV-2 N protein in the linear range of 0.005–50 ng mL−1 with a low detection limit of 1.8 pg mL−1 (S/N = 3). The immunosensor displays extraordinary sensitivity, strong anti-interference, and high reproducibility in detecting SARS-CoV-2 N protein, which envisages its potential application in the clinical diagnosis of COVID-19. [ABSTRACT FROM AUTHOR]

[Display omitted] • A sustainable and facile self-activation strategy is proposed to synthesize high N-doped hierarchical porous carbon (HNHPC) for CDI. • The synthesized HNHPC PUA possesses ultrahigh specific surface area (3280.16 m2/g), splendid pore volume (2.49 cm3/g), large mesopore ratio (57.83%) and high N content (6.4%). • The small hierarchical porous carbon nanogranlue structure of HNHPC PUA helps to expose more accessible and extra active sites, accelerating the ions insertion and extraction from the micropores. • The HNHPC PUA delivered a splendid desalination capacity of 24.86 mg/g and good cycling stability. High N-doped hierarchical porous carbon (HNHPC) with ultrahigh BET surface area (S BET) and pore volume (V pore) has attracted great attention in capacitive deionization (CDI) due to the copious active sites. However, the traditional methods often adopt strong corrosive activators and fail to achieve high N-doping, which are harmful for its practical application. Herein, we develop a sustainable CO(NH 2) 2 -C 6 H 5 O 7 (NH 4) 3 -co-assisted C 6 H 5 K 3 O 7 (U-A-co-assisted P) self-activation strategy to prepare ultrahigh S BET and V pore HNHPCs for CDI desalination. Compared to the single P self-activation and U/A-assisted P self-activation, HNHPC PUA acquired via U-A-co-assisted P self-activation possesses ultrahigh S BET (3280.16 m2/g), splendid V pore (2.49 cm3/g), high V meso /V pore (57.83%) and high N-doping (6.40%). Its small hierarchical porous carbon nanogranlue structure helps to expose more accessible S BET and extra active sites, accelerating the ions insertion and extraction from the micropores. The resultant HNHPC PUA delivers a high specific capacitance of 203.9F/g. In the assembled CDI setup, HNHPC PUA exhibits a superior salt adsorption capacity (SAC) of 24.86 mg/g, a rapid salt adsorption rate (SAR) of 8.29 mg/g/min and reaches 88.7% SAC retention after 50 cycles in 500 mg/L NaCl at 1.2 V, suggesting good application potential. Overall, this work provides new insight into rapidly preparing ultrahigh S BET and V pore HNHPCs for energy and environmental applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • DMI form organic layers on the surface of zinc sheets by plane adsorption. • The addition of DMI disrupts the hydrogen bond network in the electrolyte. • DMI molecules regulate the solvation sheath structure of Zn2+ in the electrolyte. • The addition of DMI optimize the deposition behavior of Zn2+ on different substrates. The cycle life of aqueous Zn-metal batteries is greatly challenged due to the formation of Zn dendrites on the electrode surface and side reactions. Herein, an effective tactic against the above problems was proposed by adding 1,3-dimethyl-2-imidazolidinone (DMI) to the ZnSO 4 electrolyte to form an inert organic layer on the surface of the zinc foil, and the protective mechanism of DMI molecules on the surface of zinc poles was discussed by density functional theory. The formation of this inert layer can protect the zinc foil from being eroded by H 2 O, homogenize the electric field on the electrode surface and inhibit the formation of dendrites. The addition of DMI also destroys the original hydrogen bond network in the system and suppresses the side reaction problem caused by the Grotthuss mechanism. This new electrolyte can effectively improve the cycle performance of different half-batteries. In ZnSO 4 -DMI-05 electrolyte, the Zn||Zn cell achieved stable cycling for 2400 h at a current density of 1.0 mA cm−2 (1.0 mAh cm−2). Furthermore, it was applied to a Zn||VS 2 full cell and cycled for 600 cycles at a current density of 1 A/g, achieving a coulombic efficiency (CE) of 99.97 % and a capacity retention rate of 95.33 %. This organic additive enables ultrastable and reversible deposition of zinc ions on different types of substrates in an aqueous environment, providing a promising approach for the development of aqueous zinc-metal batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • N-doped 3D hierarchical porous carbons (3DNHPCs) are prepared in a green strategy. • Tertiary porous structure and surface-exposed active sites accelerate ion insertion. • Superior desalination capacity and rapid desalination rate are achieved. • Ultrahigh water recovery and productivity are acquired. Exploiting a sustainable and effective strategy for fabricating 3D N-doped hierarchical porous carbon (3DNHPC) for capacitive deionization (CDI) is a huge challenge for desalination. The traditional methods often adopt expensive precursors, complex routes and strong corrosive activators that are harmful for its practical application. Herein, a novel green double organic salt activation strategy is developed that utilizes lotus stem (LS) with a regular 3D macroarray structure to acquire 3DNHPC x. Different from single C 6 H 5 K 3 O 7 or Na 2 EDTA activation, 3DNHPC x obtained under double organic salt co-activation exhibits a suitable micro-meso-macro porous structure with a high BET surface area (S BET) of 2256.2 m2/g, a large pore volume of 1.02 cm3/g, a remarkable mesoporous volume of 0.41 cm3/g and 1.31 % N content. Its unique tertiary pore structure and copious surface-exposed active sites facilitate the ions rapid insertion and extraction from the micropores. The assembled CDI cells achieve a superior salt removal capability of 25.36 mg/g as well as a splendid volumetric adsorption capacity (VAC) of 6.21 mg/cm3 and an ultrafast average salt removal rate of 7.84 mg/g/min. Meanwhile, 3DNHPC 11 maintain 89.4 % adsorption capacity after 50 cycles. Besides, 3DNHPC 11 obtains a high water recovery (WR) of 82.2 % and high productivity of 290 g NaCl /g C /(h m2) or 108.1 g NaCl /cm3 C /(h m2). This work sheds light on one way to design economical and eco-friendly 3DNHPCs for high-performance CDI desalination. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co(OH) 2 nanosheets in-suit anchored hydroxylated hollow tubular g-C 3 N 4 was obtained. • CNH with abundant –OH induced formation of the key PMS activation species CoOH+. • The sp3 hybridization introduced by OH− greatly facilitated charge transfer. • ERF atoms with high Fukui index were active sites for electrophilic attack. Cobalt-based materials were considered as promising catalysts for peroxymonosulfate (PMS) activation, while few reactive sites and ion leaching limit its environmental application. Herein, Co(OH) 2 nanosheets in-situ anchored hydroxylated hollow tubular g-C 3 N 4 (Co/CNH) was successfully fabricated by a facile impregnation method, and used to activate PMS for enrofloxacin hydrochloride (ERF) degradation. Compared with neat Co(OH) 2 and CNH, the optimum catalyst (10 %Co/CNH) exhibited higher ERF degradation efficiency for 95.6 % within 30 min. The enhanced performance was attributed to the synergistic effect between Co(OH) 2 and CNH. CNH can not only provide numerous nucleation sites for Co(OH) 2 to inhibit its agglomeration, but also provide abundant OH− for formation of the key PMS activation species CoOH+. Furthermore, DFT-based electron density difference elucidated that the sp3 hybridization introduced by OH− greatly facilitated charge transfer from 10 %Co/CNH to PMS. A series of characterization verified that 1O 2 dominated the degradation of ERF (nonradical pathway), SO 4 •− and •OH (radical pathway) as well as electron transfer also contributed to this process. Fukui index (f −) and bond degree (BD) indicated that reactive oxygen species tend to attack atoms with higher f − and scavenge covalent bonds with larger BD in the process of ERF degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] • CuMnS as a fluorescent probe for the first time and used for the detection of OTC. • CuMnS performs excellently for OTC in actual river water and tap water detection. • Reveal the microscopic mechanism of fluorescence quenching of CuMnS by OTC. The novel CuMnS nanoflower fluorescent probe based on Mn-doped CuS was developed to achieve the fluorescence detection of oxytetracycline hydrochloride (OTC), the fluorescent sensor has good selectivity and stability. The doping of Mn significantly increased the fluorescence intensity of CuS, which was above 10 times that of CuS. When the predominant species of OTC molecule was zwitterionic OTC+/−at the solution pH of about 5.00, the fluorescence quenching efficiency of CuMnS by OTC reached the highest. Through fluorescence lifetime and UV absorption, the sensing mechanism between CuMnS and OTC was found to be static quenching. Moreover, Multiwfn wavefunction analysis program based on density function theory (DFT) calculation was applied to compare the interactions between different OTC species and CuMnS at different pH, to reveal the micromechanism of fluorescence quenching of CuMnS by OTC from the views of atoms. The molecular surface quantitative analysis and basin analysis of different OTC species demonstrated that the N atom and O atoms of tricarbonylamide moiety of zwitterionic OTC+/− can provide lone pair electrons to form a non-fluorescent ground state complex with CuMnS. Meanwhile, the electrostatic attraction of OTC+/− with negatively charged CuMnS was also beneficial to the interaction, resulting in the effective fluorescence quenching of CuMnS. This work offers a convenient method for sensitively detecting OTC and broadens the application of CuMnS in the field of fluorescence detection. [ABSTRACT FROM AUTHOR]

Rapid, convenient and accurate detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is urgently needed to timely diagnosis of coronavirus pandemic (COVID-19) and control of the epidemic. In this study, a signal-off photoelectrochemical (PEC) immunosensor was constructed for SARS-CoV-2 nucleocapsid (N) protein detection based on a magnetic all-solid-state Z-scheme heterojunction (Fe 3 O 4 @SiO 2 @TiO 2 @CdS/Au, FSTCA). Integrating the advantages of magnetic materials and all-solid-state Z-scheme heterostructures, FSTCA was implemented to ligate the capture antibody to form magnetic capture probe (FSTCA/Ab 1). It can simplify the separation and washing process to improve reproducibility and stability, while allowing immune recognition to be performed in the liquid phase instead of the traditional solid-liquid interface to improve anti-interference. Besides, the heterojunction inhibited the recombination of photogenerated electron/hole (e-/h+) and promoted the light absorption to provide superior photoelectric substrate signal. The mechanism of photogenerated e−/h+ transfer of FSTCA were investigated by the electron spin resonance (ESR) spectroscopy. SiO 2 spheres loaded with Au NPs utilized as an efficient signal quencher. The steric hindrance effect of SiO 2 @Au labeled detection antibodies (SiO 2 @Au-Ab 2) conjugates significantly diminished light absorption and hindered the transfer of photogenerated electrons, further amplifying the signal change value. Based on the above merits, the elaborated immunosensor had a wide linear range of 10 pg mL−1–100 ng mL−1 and a low detection limit down to 2.9 pg mL−1 (S/N = 3). The fabricated PEC immunosensor demonstrated strong anti-interference, easy operation, and high sensitivity, showing enormous potential in clinical diagnosis of SARS-CoV-2. [Display omitted] • A PEC immunosensor was developed based on FSTCA for detecting SARS-CoV-2N protein. • FSTCA owns strong magnetic response and exceptional PEC performance • Immune recognition was performed in liquid phase and process was simplified. • The mechanism of photogenerated e− /h+ transfer of FSTCA were investigated by the ESR. • The immunosenor possessed a low detection limit of 2.9 pg mL−1. [ABSTRACT FROM AUTHOR]

[Display omitted] • The novel adsorbent of UiO-66-NH 2 @Mg(OH) 2 was prepared and characterized. • The adsorption capacity was improved significantly after modification. • Adsorption behavior and mechanism of phosphate on UNM were explored. • Multiwfn wave function methods were applied to interpret the adsorption mechanisms. • Phosphate was successfully recovered by the struvite-based method. Two serious challenges of water eutrophication and phosphorus resources exhaustion make the P recovery imperative. In this work, a novel phosphate adsorbent UiO-66-NH 2 @Mg(OH) 2 (UNM) has been synthesized by the in-situ growth of magnesium hydroxide nanosheets around UiO-66-NH 2. The batch adsorption experiments were carried out by controlling the single variate (such as pH, initial concentration, contact time, temperature and interfering anions) to explore the adsorption behaviors. And the adsorption dynamics and isotherms fit well with the pseudo-second-order (PSO) and Langmuir models, combined with the thermodynamics results, indicating a spontaneous and endothermic monolayer chemisorption process. Besides, the maximum phosphate adsorption capacity of UNM was calculated as 408.07 mg/g (≈130.39 mg P/g) at pH = 6.0, T = 298 K. A series of characterizations (XRD, FT-IR, SEM, EDS, BET, TGA, XPS, ICP-MS et. al) and quantum chemical analysis methods (ESP, ALIE and Hirshfeld surface) was applied to predict the reactive sites. The possible mechanism can be deduced as two continuous steps: the physical attraction by weak interactions and the chemical adsorption with an ion-exchange mechanism. The UNM also presented high removal efficiency in the environmental water samples and showed satisfactory reusability and excellent chemical stability in the recycling process. From the desorption effluents, we successfully recycled the struvite with 14.31% P content. Therefore, the UNM will be regarded as a promising phosphate adsorbent in practice and this work will provide inspiration and guidance for the design and preparation of high-efficiency P-removal adsorbents. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hierarchically floral ZC@PANI@NiAl-LDH composite was prepared and characterized. • Experiment and theoretical calculations interpret the adsorption mechanisms. • LOL-π, π electron density, and IRI-π isosurface indicate the π-π interaction. • IGMH and Hirshfeld surface analyses reveal the hydrogen bond interaction. • Saccharin and NiAl-LDH act as the H-bond acceptor and donor, respectively. In this work, ZIF-8 derived carbon@polyaniline@Ni/Al layered double hydroxides (denoted as ZC@PANI@NiAl-LDH) composite has been successfully designed via the facial synthesis of the ZIF-8, followed by high-temperature pyrolysis, oxidative polymerization of polyaniline, and in-site growth of NiAl-layered double hydroxides. Meanwhile, the composite acts as an advanced adsorption material for the scavenging of saccharin from aqueous solutions. Moreover, benefiting from the unique three-dimensional (3D) hierarchically floral structure and various functional groups, the as-prepared ZC@PANI@NiAl-LDH composite presents a high adsorption capacity (498.5 mg/g) for saccharin, superior to other reported adsorbents. Besides, the ZC@PANI@NiAl-LDH possesses rapid adsorption kinetics and excellent reusability performance. Furthermore, Fourier transformed infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) analyses initially reveal the possible adsorption mechanism, including electrostatic interactions, π-π interactions, and hydrogen bonding. Quantum chemical theory calculations further indicate the above adsorption mechanism. Significantly, based on the Hirshfeld surface analyses, saccharin behaves as the H-bond acceptor, while the NiAl-LDH works as the H-bond donor. This work provides a feasible strategy to design advanced materials for practical wastewater treatment. [ABSTRACT FROM AUTHOR]