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A simple, efficient, and environmentally friendly electro-Fenton (EF) process is highly demanded for EF practical application. Herein, a highly practical double-cathode EF system has been developed...

Although graphitic carbon nitride (g-C3N4) has been identified as a promising photocatalyst, pristine g-C3N4 has a limited light absorption, insolubility, small specific surface area, and rapid ele...

Electrochemical reduction of nitrate (NO3-) to ammonia (NH3) provides a promising route for recycling nitrate from wastewater to balance the nitrogen cycle and sustainable production of ammonia. Among various catalytic materials for NO3- electroreduction, Cu shows a favorable selectivity to NH3. However, Cu can be easily oxidized, while the effect of the Cu oxidation state on NO3- reduction remains to be elucidated. Here, we report that oxidic Cu formed on a Cu electrode can enhance its activity and selectivity for NO3- reduction to NH3. We first used a polished Cu foil as a model catalyst for NO3- reduction and found that a brief exposure of the Cu electrode to air could increase its yield rate and Faradaic efficiency for NH3 production. The improved catalytic performance was attributed to the formed Cu+ sites that can reduce the energy barrier for NO3- reduction to NH3 and suppress the competing HER reaction. Based on this finding, an oxide-derived Cu (OD-Cu) electrode was prepared by annealing a Cu foil in O2 gas followed by electroreduction, which exhibited superior performance for NO3- reduction to NH3, with a Faradaic efficiency of 92% and a yield rate of 1.1 mmol h-1 cm-2 for NH3 production at -0.15 V versus reversible hydrogen electrode. Moreover, an OD-Cu foam electrode was similarly developed to demonstrate NO3- recycling from a low-concentration NO3- solution, which showed a nearly 100% conversion of NO3- to NH3 using a circulating flow cell.

In this paper, a slag compound binder (hereinafter referred to as the SM binder) was used to bind seashore saline soil. Compressive tests, scanning electron microscopy, energy-dispersive spectroscopy and X-ray diffraction analytical tests were carried out to measure the unconfined compressive strength, observe the microstructure, analyze the composition of hydration products and evaluate the binding mechanism of the saline soil/SM binder mixture. The results showed that calcium silicate and calcium aluminate hydrates were produced after the hydration of the cinder components in the SM binder. Part of the calcium aluminate hydrate reacted with the gypsum to form ettringite, while the other part reacted with the Cl− and SO42− in the saline soil to produce Kuzel’s salt. Na+ also participated in the hydration reaction and produced zeolite-like substances. These hydration reactions led to the rapid binding of the soil sample. As the surface of the saline soil particles also contained active SiO2 and A12O3, the Ca(OH)2 reacted with them to form calcium silicate and calcium aluminate hydrates in a continuously alkaline environment. Such reactions contributed to the third-stage binding of the saline soil, leading to a gradual increase in the strength of the soil samples during the middle and late stages of binding.

Exciton polarization dissociation, charge transfer and surface electron density in photocatalysts are crucial for photocatalytic hydrogen evolution reactions (HERs). In this study, crystalline carbon nitride with cyanamide defect edges (crystalline CCN) was synthesized by one step polymerization of urea in the presence of KCl. The texture and electronic band structure of carbon nitrides could be facilely tailored by changing KCl dosage. The light absorption edge of crystalline CCN extended to 736 nm due to n→π* electron transition. The enhanced dielectric constants of crystalline carbon nitrides promoted exciton polarization dissociation. The small effective electron mass (me*) in crystalline CCN facilitated me* diffusion. The efficient separation of electrons and holes benefited the formation of internal electric field, showing an 8.56-fold promotion in electron transfer compared to pristine CN. Significantly, femtosecond time-resolved transient absorption demonstrated that the surface electron density on crystalline CCN was enhanced in the presence of salt ions (NaCl). As a result, crystalline CCN exhibited 14.9 times higher HER rate than pristine CN under visible light irradiation. The apparent quantum yield for H2 evolution on crystalline CCN reached to 42% at 420 nm and 9% at 500 nm. This study gets a comprehensive understanding of photocatalytic HERs using carbon nitride photocatalysts.

Benzophenone derivatives, including benzophenone-1 (C13H10O3, BP1), benzophenone-3 (C14H12O3, BP3) and benzophenone-8 (C14H12O4, BP8), that used as UV filters are currently viewed as emerging contaminants. Degradation behaviors on co-exposure benzophenone derivatives using UV-driven advanced oxidation processes under different aqueous environments are still unknown. In this study, the degradation behavior of mixed benzophenone derivatives via UV/H2O2 and UV/peroxydisulfate (PDS), in different water matrices (surface water, hydrolyzed urine and seawater) were systematically examined. In surface water, the attack of BP3 by hydroxyl radicals (HO∙) or carbonate radicals (CO3∙-) in UV/H2O2 can generate BP8, which was responsible for the relatively high degradation rate of BP3. Intermediates from BP3 and BP8 in UV/PDS were susceptible to CO3∙-, bringing inhibition of BP1 degradation. In hydrolyzed urine, Cl− was shown the negligible effect for benzophenone derivatives degradation due to low concentration of reactive chlorine species (RCS). Meanwhile, BP3 abatement was excessively inhibited during co-exposure pattern. In seawater, non-first-order kinetic behavior for BP3 and BP8 was found during UV/PDS treatment. Based on modeling, Br− was the sink for HO∙, and the co-existence of Br− and Cl− was the sink for SO4∙-. The cost-effective treatment toward target compounds removal in different water matrices was further evaluated using EE/O. In most cases, UV/H2O2 process is more economically competitive than UV/PDS process.

Although Fe-chitosan adsorbents are attractive for removing arsenite from water, the practical applications of these granular adsorbents are mainly limited by slow adsorption kinetics. In this study, radially porous Fe-chitosan beads (P/Fe-CB) were prepared using freeze-casting technique. The P/Fe-CB particles possess radially aligned micron-sized tunnels from the surface to the inside as well as excellent acid resistance. Kinetic studies show that the adsorption equilibrium time of P/Fe-CB to 0.975 mg/L As(III) (within 240 min) is considerably shorter than that of compact Fe-chitosan beads (over 600 min). The maximal adsorption capacity of P/Fe-CB for As(III) is 52.7 mg/g. It can work effectively in a wide pH range from 3 to 9, and the coexisting sulfate, carbonate, silicate and humic acid have no significant effect on As(III) removal. The addition of H2O2 can further accelerate and promote the As(III) removal except at high pH (11) and phosphate concentration (50 mg/L). The fixed-bed experiments demonstrate that the P/Fe-CB column can effectively treat about 3000 bed volume (BV) of simulated As(III)-containing groundwater to meet the drinking water standard (

Metallic 1T phase molybdenum disulfide (1T-MoS2) holds great promise in energy storage applications due to its excellent conductivity and hydrophilicity. However, free 1T-MoS2 nanosheets are prone to agglomeration and convert to 2H-MoS2, resulting in a decrease in electrochemical performance. In this study, metallic 1T phase MoS2 nanosheets are confined among TiO2 nanotube arrays (1T-MoS2@TiO2/Ti) via a facile hydrothermal process. The architecture in the glory of ultrathin 1T-MoS2 nanosheets and highly ordered pore tunnel of TiO2 nanotube arrays benefits fast electrolyte diffusion and electron transfer. As a result, the 1T-MoS2@TiO2/Ti composite shows a high specific capacitance of 428.1F g−1 at 0.2 A g−1, high energy density of 48.2 Wh kg−1, high power density of 2481.7 W kg−1 and 97% capacitance retention after 10,000 cycles. This study proves an artful thought for designing electrode materials to enhance their electrochemical performances.

Although oxidation of As(III) to As(V) is deemed necessary to promote arsenic removal, the oxidation process usually involves toxic byproducts, well-defined conditions, energy input or sludge generation. Moreover, extra operations are required to remove the resulting As(V). A heterogeneous catalytic process of CuFe2O4 with peroxymonosulfate (PMS) is established for As(III) oxidation and adsorption. The PMS can be activated by CuFe2O4 to generate radical species for As(III) oxidation. The CuFe2O4/PMS has a stronger affinity for arsenic than CuFe2O4 alone. Oxidation and adsorption promote each other. As a result, the heterogeneous catalytic process is more efficient for As(III) removal than a preoxidation of As(III) followed by adsorption. The adsorption capacity for As on CuFe2O4/PMS reached up to 63.9 mg/g, which is much higher than that of As(III) (36.9 mg/g) or As(V) (45.4 mg/g) on CuFe2O4 alone. The process can work effectively over a wide range of pH values (3–9) and temperatures (10–40 °C). Coexisting ions such as sulfate, carbonate, silicate and humic acid have an insignificant effect on As(III) removal. The As(III) (1415 μg/L) can be completely oxidized to As(V) and rapidly removed to below 10 μg/L (less than 15 min) using CuFe2O4(0.2 g/L)/PMS(100 μM). Moreover, the As(III) (50 μg/L) can be completely oxidized and removed within 1 min. The proposed process is easily applicable for the remediation of As(III)-contaminated water under ambient conditions.

Exploring and designing an efficient and robust photocatalyst toward the degradation of organic pollutants under nature sunlight irradiation is a challenging research topic. The ability to maintain the photocatalytic activity in the entire daytime will be the ultimate goal for further widespread application of solar energy-driven semiconductor photocatalysis. Here, an all-day-active Z-scheme photocatalytic system is reported by employing Ag@AgI nanoparticles decorated Ag3PO4 cubes (C-Ag3PO4@Ag@AgI). By coupling the pronounced carrier separation as well as increased stability, the C-Ag3PO4@Ag@AgI is capable of performing efficient Rhodamine B (RhB) and bisphenol A (BPA) degradation under sunlight irradiation, and still persist noticeable activity when the light is very weak. The RhB (20 mg/L, 50 mL) can be completely degraded by C-Ag3PO4@Ag@AgI (30 mg) within 1 h with the average luminous power of 117.5 mW (3.14 cm2). Dramatically, the as-prepared samples can still maintain photocatalytic activity even in a cloudy day (0.2–6.7 mW). This work has offered a valuable concept of continuous pollutant removal under nature sunlight irradiation in the entire daytime, which may serve as a model system for the wide environment applications, such as the removal of low-level pollutants under weak light irradiation.

Oxcarbazepine (OXC) is ubiquitous in the aqueous environment. And due to its ecotoxicological effects and potential risks to human, an effective way to eliminate OXC from aqueous environment has aroused public concerns in recent years. Radical-based reactions have been shown to be an efficient way for OXC destruction, but the reactions of OXC with reactive oxygen species (ROS) and carbonate radical (CO3•−) are still unclear. In this study, we focused the degradation of OXC and ROS, CO3•− generation mechanism, and their roles in OXC degradation via UV and UV/H2O2. The triplet state of oxcarbazepine (3OXC∗) was found to play an important role in OXC degradation via UV. And hydroxyl radicals (•OH) and singlet oxygen (1O2) were found to be the dominant ROS in OXC degradation. Superoxide radical (O2•−) did not react with OXC directly, but it may react with intermediate byproducts. Generation of CO3•− played a positive role on OXC degradation for both UV and UV/H2O2. In addition to •OH, 3OXC* also contribute to CO3•− production. The second-order rate constants of OXC with •OH and CO3•− were 1.7 × 1010 M−1 s−1 and 8.6 × 107 M−1 s−1, respectively. Potential OXC degradation mechanisms by •OH were proposed and included hydroxylation, α-ketol rearrangement, and benzylic acid rearrangement. Compared with non-selective •OH, the reactions involving CO3•− are mainly electron transfer and hydrogen abstraction. And the acute toxicity of OXC was lower after UV/H2O2 and UV/H2O2/HCO3− treatments, which was confirmed by luminescent bacterial assay (Vibrio fischeri bacterium).

g-C3N4 has recently emerged as a promising photocatalyst for solar energy conversion. Nonetheless, attempts to enhance its inherently low activity are rarely based on precise molecular tunability strategy. In this study, two-type cyanamide defects-grafting g-C3N4 (CCN) was prepared through the thermal polymerization of thiourea in the presence of KCl. Stable potassium isothiocyanate (KSCN) was in situ generated via thiourea isomerization and then reacted with different amino groups ( NH2 and NH) in tri-s-triazine rings to obtain two-type cyanamide defects. Theoretical calculations and experiment results confirm that the ratio of the two-type cyanamide defects could be adjusted by KCl dosage, accompanying tunable energy levels of CCN. The charge carrier transfer and separation of CCN was greatly improved. Furthermore, the existence of cyanamide defects hindered the formation of intermolecular hydrogen bonds among g-C3N4, which facilitated the formation of porous structure and exposed more active sites for photocatalytic hydrogen evolution reaction (HER). As a result, the optimized photocatalyst (CCN-0.03) showed a high HER rate of 4.0 mmol g−1h−1, which was 5 times higher than 0.8 mmol g−1h−1 for pristine g-C3N4. And the apparent quantum efficiency reached up to 14.65% at 420 ± 10 nm. The findings deepen the understanding on precise molecular tuning of g-C3N4.

Integration of oxidation and adsorption of adsorbents is highly desired to deep remove As(III) in groundwater. In this study, a superparamagnetic Fe3O4@SiO2@Fe2O3- CuO/TiO2 (Mag@Fe-Cu/TiO2) adsorbent was synthesized using step-by-step precipitation process. The TiO2 nanoparticles were rationally positioned onto the shell of Fe2O3-CuO for oxidization of As(III). The Fe2O3-CuO binary oxide significantly improved As(III, V) adsorption compared to individual oxide (Fe2O3 or CuO). The ingenious design of the adsorbent could give full play to oxidation and adsorption functions. As a result, Mag@Fe-Cu/TiO2 showed much better As(III) removal performance than Mag@Fe-Cu-TiO2 prepared by co-precipitation. The maximal adsorption capacity of Mag@Fe-Cu(7)/TiO2(8.74) for As(III) reached to 17.49 mg/g under UV irradiation. The removal of As(III) in groundwater was tested using Mag@Fe-Cu/TiO2 adsorbent. Almost all the As(III) were removed under UV irradiation (t = 24 h for C0 = 1–5 mg/L or 12 h for C0 = 20–1000 μg/L, adsorbent dose = 1 g/L, pH = 7.0, T = 25 °C). Moreover, it could be easily separated from treated water with an external magnet and well reused maintaining a high As(III) adsorption capacity. Furthermore, the adsorbent could effectively treat arsenic spiked natural groundwater. The adsorption followed the inner-sphere complex mechanism via the chemical interactions between metal (M: Fe and Cu) and arsenic species (As) forming M O As bonds.

Prednisolone (PDNN) as an emergent micropollutant directly influences the regional ecological security. In this study, the degradation of PDNN by ultraviolet activated chlorine (UV/chlorine) oxidation process was comprehensively evaluated. The quenching experiment suggested that the PDNN degradation in UV/chlorine process was involved in the participation of hydroxyl radical ( OH) and reactive chlorine species (RCS). Influence factors including chlorine dosage, pH, common anion and cation, fulvic acid (FA) on PDNN degradation via UV/chlorine process were investigated. A low chlorine (≤7.1 mg L−1) promoted the PDNN degradation, while a high chlorine dosage (>7.1 mg L−1) was adverse. The pH (4.0–10.0) showed negligible effect, while the investigated anions (Cl−, Br−, HCO3− and SO42−), NH4+ and FA exerted negative impact on PDNN degradation. An efficient process to minimize pharmaceutical micropollutants was the disposal of human urine containing a high concentration of pharmaceutical and potential toxic metabolites. An inhibitory effect was observed in the synthetic urine (fresh urine and hydrolyzed urine). The intermediates/products were identified and the mechanism of PDNN degradation was proposed. PDNN gone through three degradation routes, involving the direct addition of α, β-unsaturated ketone at C1 or C5, the photolysis of C17 and H-abstraction of C11. The main reactive sites were further determined by comparison of the frontier orbitals calculation and the proposed mechanism. Based on the toxicological tests for PDNN degradation, TP396 (TP396-C1Cl and TP396-C5Cl) and TP414-2-1 (TP414-C1Cl C5OH) exhibited much higher toxicity than PDNN, and prolonging reaction time was necessary to achieve PDNN detoxification.

Iron oxide-modified biochars are increasingly recognized as a promising arsenic adsorbent. However, most of them face serious challenges in the rapid and efficient removal of As(III). Herein, we integrated the iron oxide nanoneedles vertically covered biochar fibers (Fe-BFs) with H2O2 and Hydroxylamine (HA) to construct a heterogeneous catalytic system for the rapid oxidation and deep removal of As(III) from water. The system oxidized the As(III) to As(V) with high efficiency, and then the generated As(V) could be rapidly removed by adsorption onto Fe-BFs. The removal efficiency of As(III) by Fe-BFs/H2O2/HA at 120 min reached up to 98.93%, which is much higher than that of by Fe-BFs (69.20%) and Fe-BFs/H2O2 (92.32%). The system could work reliably in a wide pH range (4–10). Moreover, fixed-bed column experiments demonstrated that the addition of H2O2 and HA could increase the effective treatment volume from ~350 bed volume (BV) to ~700 BV to meet the drinking water standard ( OH. The OH played a very important role in promoting the removal of As(III). This study offers a new strategy to enhance the applicability of Fe modified biochar for As(III) removal.

Phenicol antibiotics (PABs) degradation by UV/H2O2 is important because we need to determine the reduction in toxicity and disinfection byproducts for post-chlorine. In this study, the degradation of PABs, including florfenicol (FLO), chloramphenicol (CAP) and thiamphenicol (THA), was examined. The pseudo-first order degradation rate constants of PABs were 3 times higher in ultrapure water (UW) than that in synthetic wastewater (SW) for these conditions: [PABs]0 = 1 μM, [H2O2] = 0.1 mM, and I0 = 1.985 × 10−6 E L−1 s−1. Fulvic acid (FA) and HCO3– inhibited PABs degradation, Cl− and NO3– concentrations of up to 5 mM and 10 mM had a negligible impact. The impact of water matrix on PABs degradation was successfully predicted using pseudo-steady-state kinetic model. The degradation of PABs was triggered via hydroxylation and/or hydrogen abstraction. The treatment of PABs via UV/H2O2 could decrease their antimicrobial properties, while the byproducts of FLO and THA showed higher acute toxicity in Vibrio fischeri. In addition, two identification products (TP-276 and TP-354) of FLO had higher ecotoxicity toxicity (using ECOSAR) in fish, daphnid and green algae. The trichloromethane formation potential (TCMFP) for PABs with post-chlorination in UW and SW can be reduced after UV/H2O2 compared to UV, and is related to the corresponding decrease of dissolved organic carbon (DOC).

Although noble metal electrocatalysts are highly efficient in the dehalogenation of halogenated antibiotics, the prohibitive cost hinders their practical applications. In this study, a cobalt-phosphorous/oxide (Co P/O) composite prepared via a one-step electrodeposition was for the first time applied in electroreductive dechlorination of halogenated antibiotics (HA), including chloramphenicol (CAP), florfenicol (FLO) and thiamphenicol (TAP). Co P/O had a higher FLO dechlorination efficiency (91%) than Pd/C (69.3%) (t = 60 min, C0 = 20 mg L−1, applied voltage of −1.2 V vs. saturated calomel electrode (SCE)). Furthermore, the dechlorination efficiencies of Co P/O for CAP and TAP reached to 98.7 and 74.2%, respectively. The electron spin resonance and in situ Raman characterizations confirmed that atomic H* was produced via the Co P and the formation of Co Cl bonds occurred on the Co O in Co P/O. The Co Cl bond formation could trap HA molecules onto Co P/O and weaken the C Cl bond strength. The synergistic effect of H* attack and Co Cl bond was responsible for the high dechlorination efficiency. This study offers new insights into the interface mechanism of electroreductive dehalogenation process, and shows a great potential for the remediation of halogenated antibiotics contaminated wastewater.

It is hard to balance high water permeability and good mechanical strength of hydrogel adsorbents. In this study, an enhanced double network hydrogel adsorbent of poly (vinyl alcohol)/poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PVA/PAMPS) was prepared via simple free-radical polymerization. Hydrophilic PAMPS guaranteed high swellability of the adsorbent, which made the sufficient diffusion of metal ions towards adsorbent inside. Meanwhile, the cross-linkage between PVA and PAMPS chains ensured good mechanical strength of the adsorbent. Significantly, the introduction of multifunctional groups (-NHR, -SO3H and -OH) endowed the adsorbent with both chelation and ion exchange function for enhancing heavy metal adsorption. The maximum adsorption capacities of Pb2+ and Cd2+ reached 340 and 155.1 mg/g, respectively. The adsorbent could efficiently remove heavy metals in melting effluent, especially Pb2+ and Cd2+. The removal efficiencies reached 88.1% for Pb2+, 91.4% for Cd2+, 70.4% for Zn2+, 77.4% for Cu2+, 42.5% for Mn2+, 45.1% for Ni2+ and 95.4% for Fe3+ using 2 g/L adsorbent in 2 h. Moreover, the adsorbent showed a good reusability, and the removal efficiencies maintained 94% for Pb2+ and 93% for Cd2+ in the fifth cycle (m/V = 1 g dry gel/L). This work developed a highly practical hydrogel adsorbent for heavy metal removal from wastewater.

Although UV/chlorine advanced oxidation process has been employed to treat contaminants, the roles of secondary radicals are generally negligible. The comprehensive evaluation of secondary radicals on contaminants degradation remains deficient. In this study, two typical neonicotinoid insecticides, imidacloprid (IMD) and thiacloprid (THIA), were degraded via UV/chlorine process. It is for the first time found that the existence of Cl− significantly promoted THIA degradation during UV/chlorine process, attributed to the formation of Cl2 −. In addition, the effects of pH, fulvic acid (FA), and bicarbonate (HCO3–) on the degradation of IMD and THIA were evaluated. Low pH was in favor of the degradation of IMD and THIA, while both FA and HCO3– had slight inhibition effects. Meanwhile, the degradation of IMD and THIA via UV/chlorine process was inhibited in real matrices. The existence of Br− heavily suppressed the degradation of THIA via UV/chlorine process. The initial transformation pathways of IMD and THIA involved electron transfer, H-abstraction, and then disproportionation or the methylene bridge cleavage, yielding hydroxyl and keto derivatives as well as free amine. Although the mineralization for IMD (29%) and THIA (35%) was low, the acute toxicity to Vibrio fischeri for the treated samples was lower than that for corresponding parent compounds. This study comprehensively evaluated the degradation of IMD and THIA via UV/chlorine process, highlighting Cl2 − as an important reactive species for THIA elimination.

High adsorption capacity, fast adsorption kinetics, good reusability and low cost are highly demanded for adsorbents used in practical adsorption process. In this study, a porous double network Jute/Polyacrylic acid (Jute/PAA) gel was prepared using simple free-radical polymerization of acrylic acid in Jute aqueous solution. The high permeability of Jute/PAA hydrogel with about 80 wt% water made internal adsorption sites fully expose to metal ions. The Jute/PAA gel adsorbent could efficiently adsorb heavy metals in melting wastewater, especially Cd2+ and Pb2+. The adsorbent showed very high adsorption capacities of 401.7 mg/g for Cd2+ and 542.9 mg/g for Pb2+. Moreover, the adsorption equilibrium reached within only 10 min for 40 mg/L of Cd2+ and Pb2+ using 1 g/L adsorbent. Meanwhile, the removal efficiencies reached 81.0% for Pb (C0 = 3.825 mg/L), 79.3% for Cd (C0 = 6.075 mg/L), 83.4% for Cu (C0 = 9.325 mg/L), 29.8% for Zn (C0 = 188.6 mg/L), 22.3% for Mn (C0 = 17.05 mg/L), 96.2% for Cr (C0 = 0.25 mg/L) and 99.8% for Fe (C0 = 9.75 mg/L) in melting wastewater using 1 g/L adsorbent in 2 h. In particular, the concentrations of Pb, Cd and Cr decreased below 0.001 mg/L using 4 g/L adsorbent. In the fixed-bed column experiments, the treatment volume of melting wastewater reached 2900 BV (32.8 L) only producing 50 BV (565 mL) eluent. This work develops a highly practical adsorption process based on hydrogel adsorbents for the removal of heavy metals in actual wastewater.

The direct biological treatment of antibiotics containing wastewater brings about a potential risk of antibiotic resistance genes (ARGs) spread. Although advanced oxidation technologies based on photocatalysis generally appear effective at degrading antibiotics in wastewater, the fate of ARGs in succeeding biological treatment system is still unknown. Herein, a filter-membrane-like carbon cloth-immobilized Fe2O3/g-C3N4 photocatalyst is fabricated through immersion-calcination method. Peroxydisulfate-coupled photocatalysis system is developed to degrade tetracycline (TC, an emerging refractory antibiotic pollutant). The system can produce energetic active species (·OH, SO4·−, h+, O2·− and 1O2), exhibiting a superior performance towards TC degradation in static and continuous flow processes under visible-light irradiation. The pretreatment can eliminate the antibacterial activity of antibiotics wastewater, and the chemical oxygen demand removal is greatly enhanced in subsequent anaerobic or aerobic process. The microbial diversity and richness in activated sludge for pretreated water sample are significantly higher than those for the water sample without pretreatment. Meanwhile, the pretreatment can decrease the relative abundance of potential hosts of ARGs and reduce the emergence as well as dissemination risk of ARGs. This study uncovers the effect of pretreatment of antibiotics containing wastewater using advanced oxidation technologies on the treatment efficacy and antibiotic resistome fate in biological treatment system.

Simple, efficient, and durable electrodes are highly demanded for practical electro­chemical process. In this study, a reduced graphene oxide modified nickel foam electrode (GR‑Ni foam) was facilely prepared via one-step cyclic voltammetry electrodeposition of gra­phene oxide suspension onto the Ni foam. The electrochemical degradation of nitrofuran­zone (NFZ, a kind of typical antibiotics) was studied on the GR-Ni foam cathode. The cyclic voltammetry and electrochemical impedance spectra analysis confirmed that presence of GR loading accelerated the electron transfer from the cathode surface to NFZ. With the applied cathode potential of −1.25 V (vs. Ag/AgCl), the removal efficiency of NFZ (C0 = 20 mg L−1) at the GR-Ni foam electrode reached up to 99 % within 30 min, showing a higher reaction rate constant (0.1297 min−1) than 0.0870 min−1 at the Pd-Ni foam and 0.0186 min−1 at the Ni foam electrode. It was also found that the pH, dissolved oxygen and NFZ initial concentration have slight effect on NFZ degradation at the GR-Ni foam electrode. The reactions first occurred at nitro groups (-NO2), unsaturated C=N bonds and N-N bonds to generate furan ring-containing products, and then these products were transformed into linear diamine products. The direct reduction by electrons was mainly responsible for NFZ reduction at the GR-Ni foam electrode. Even after 18 cycles, the removal efficiency of NFZ still reached up to 98 % within 1 h. In addition, the cathodic degradation process could eliminate the antibacterial activity of NFZ. The GR-Ni foam electrode would have a great potential in electrochemical process for treating wastewater containing furan antibiotics.

Biochar adsorbents for removing As(III) suffer from the problems of low adsorption capacity and ineffective removal. Herein, a granular MgO-embedded biochar (g-MgO-Bc) adsorbent is fabricated in the form of millimeter-sized particles through a simple gelation-calcination method using chitosan as biochar sources. High-density MgO nanoparticles are evenly dispersed throughout the biochar matrix and can be fully exposed to As(III) through the rich pores in g-MgO-Bc. These features endow the adsorbent with a high adsorption capacity of 249.1 mg/g for As(III). The g-MgO-Bc can efficiently remove As(III) over a wide pH of 3–10. The coexisting carbonate, nitrate, sulfate, silicate, and humic acid exert a negligible influence on As(III) removal. 300 μg/L of As(III) can be purified to far below 10 μg/L using only 0.3 g/L g-MgO-Bc. The spent g-MgO-Bc could be well regenerated by simple calcination. In fixed-bed column experiments, the effective treatment volume of As(III)-spiked groundwater achieves 1500 BV (30 L) (3 g of adsorbent, solution flow rate of 2.0 mL/min, C0 = 50 μg/L). The Mg(OH)2 generated in situ in g-MgO-Bc is responsible for the adsorption of As(III) through the inner-sphere complex mechanism. The work would extend the potential applicability of biochar adsorbent for As(III) removal to a great extent.

Resistance gene expression and microbial inhibition by halogenated antibiotics is a major environmental concern. Although electrocatalytic dehalogenation can detoxify halogenated antibiotics, the effect of dehalogenation treatment on resistance gene expression and microbial inhibition is poorly understood. Herein, a novel electrocatalyst of Fe-doped CoP nanotubes array on nickel foam (Fe-CoP NTs/NiF) is prepared through a simple ultrasonication of Fe-doped CoP nanowires hydrothermally grown on NiF. The transformation from nanowires to nanotubes improves the crystallinity of CoP and fully exposes active sites, producing energetic atomic hydrogen for dehalogenation. Fe-CoP NTs/NiF exhibits a superior dehalogenation performance towards refractory florfenicol (FLO), achieving 100% removal within 20 min (‒1.2 V vs Ag/AgCl, C0 = 20 mg L‒1). The dechlorination ratio reaches nearly 100%, and the defluorination ratio achieves 36.8% within 50 min, showing the best electrocatalytic dehalogenation performance reported so far. Microbial community and correlation analysis show that Proteobacteria is the main potential host of FLO resistance gene. Electrocatalytic reductive dehalogenation pretreatment of FLO can reduce microbial inhibition, maintaining microbial richness and diversity in the subsequent biochemical treatment unit. The electrocatalytic reductive dehalogenation treatment can significantly reduce the relative abundance of FLO resistance gene, showing a reliable process for safe treatment of halogenated antibiotic containing wastewater.

A highly stable and effective electrochemiluminescence (ECL) sensing system of cadmium sulfide nanowires/reduced graphene oxide (CdS NWS/rGO) hybrid is presented for supersensitive detection of pentachlorophenol (PCP). CdS nanowire is for the first time exploited in ECL sensing. The rGO served as both ECL signal amplifier and immobilization platform, can perfectly enhance the ECL intensity and stability of the sensing system. With S 2 O 8 2− as coreactant, the ECL signal can be significantly quenched by the addition of PCP. The established ECL sensing system presents a wider linear range from 1.0 × 10 −14 to 1.0 × 10 −8 M and a much low detection limit of 2 × 10 −15 M under the optimum test conditions (e.g., pH 7.0 and 100 mM S 2 O 8 2− ). Furthermore, the ECL sensing system displays a good selectivity for PCP detection. The practicability of the ECL sensing system in real water sample shows that this system could be promisingly applied in the analytical detection of PCP in real water environments.

It is attractive to photocatalytically purify wastewater and simultaneously convert solar energy into clean hydrogen energy. However, it is still a challenge owing to the relatively low photocatalytic efficiency of photocatalysts. In this study, we synthesized a molybdenum disulfide (MoS 2 ) quantum dot-decorated 3D nanoarchitecture (MoS 2 QDs) of indium zinc sulfide (ZnIn 2 S 4 ) and reduced grapheme oxide (MoS 2 QDs@ZnIn 2 S 4 @RGO) photocatalyst using a simple solvothermal method. The RGO promotes the electron transfer, and the highly dispersed MoS 2 QDs provides numerous catalytic sites. The photocatalytic purification of rhodamine B (RhB), eosin Y (EY), fulvic acid (FA), methylene blue (MB) and p -nitrophenol (PNP) in simulated wastewaters were further tested. The degradation efficiencies and TOC removal were 91% and 75% for PNP, 92.2% and 72% for FA, 98.5% and 80% for MB, 98.6% and 84% for EY, and 98.8% and 88% for RhB, respectively (C organics = 20 mg/L, C catalyst = 1.25 g/L, t = 12 h, I light = 3.36 × 10 −5 E L −1 s −1 ). Among these tests, the highest hydrogen production was achieved (45 μmol) during RhB degradation. Both experimental and calculational results prove that lower LUMO (lowest unoccupied molecular orbit) level of organic molecules was available for transferring electrons to catalysts, resulting in more efficient hydrogen production. Significantly, the removal efficiencies of natural organic substances in actual river water reached 76.3–98.4%, and COD reduced from 32 to 16 mg/L with 13.8 μmol H 2 production after 12 h.

The azole fungicide fluconazole (FLC) is persistent in conventional wastewater treatment plants, thus posing potential threats to human and ecosystem health. This study investigated the oxidation of FLC in aqueous solution by thermally activated persulfate (TAP) under different operation conditions. Higher temperature greatly improved the removal rate of FLC (0.057 h−1 for 30 °C and 0.223 h−1 for 60 °C) and the relationship between pseudo-first-order rate constant (kobs) and temperature fit the Arrhenius equation, with a comparatively low activation energy of 37.8 kJ mol−1. The degradation rate constants were enhanced with the increase of PS concentration during FLC oxidation (0.072 h−1 for 1.0 mM PS and 0.50 h−1 for 20 mM PS). Solution pH influenced the kobs of FLC degradation and the highest and lowest degradation rates were obtained at pH 3 (0.51 h−1) and pH 5 (0.23 h−1), respectively. Increasing the level of natural water constituents (HCO3−, Cl−, and humic acid) significantly inhibited FLC degradation. Geometry optimization of FLC was performed using density functional theory (DFT) and the data indicated that the C3 atom in the benzene ring was the most reactive site. SPE-HPLC/MS/MS analysis showed that intermediate products could form during FLC oxidation by PS and the total organic carbon (TOC) results indicated that FLC could be mineralized into CO2 and H2O. Accordingly, a plausible pathway for the degradation of FLC by the thermally activated PS could be proposed. The results of this study suggested that TAP is an applicable approach for the removal of azole fungicides in water.

The serious photocorrosion of silver phosphate (Ag 3 PO 4 ) has limited its practical applications. In this work, we propose a strategy to suppress its photocorrosion by the construction of a Z-Scheme photocatalytic system, which composed of reduced graphene oxide-enwrapped Ag 3 PO 4 (Ag 3 PO 4 @RGO) and La,Cr-codoped SrTiO 3 (La,Cr:SrTiO 3 ). Dramatically, this system shows superior anti-photocorrosion and photocatalytic performances in degradation of both RhB and 2,4-DNP. Especially for RhB, it can be completely degraded after only 5 min under intense sunlight irradiation. The improved photoactivity and anti-photocorrosion of Ag 3 PO 4 @RGO@La,Cr:SrTiO 3 can be attributed to the following: (i) The sufficient interfacial contact between Ag 3 PO 4 and RGO is favorable to transfer the carriers and lengthen the lifetime of it; (ii) the package of Ag 3 PO 4 with RGO could work as a sheltering layer to protect Ag 3 PO 4 from photocorrosion. (iii) The aggregation of photogenerated holes in the VB of Ag 3 PO 4 makes it a rich-hole region due to Z-Scheme electrons transport mechanism, which can protect Ag 3 PO 4 from the photo-reduction. This strategy provides a new thought of protecting photosensitive semiconductor from photocorrosion and could regard as an efficient application method for environmental cleaning under natural sunlight irradiation. Furthermore, it even could be extended to outdoor or indoor air cleaning in the future.

In this study, a paper spray ionization mass spectrometric (PS-MS) method was developed for the rapid in situ screening and simultaneous quantitative analysis of bisphenol A and its analogues, i.e., bisphenol S, bisphenol F, and bisphenol AF, in food packaging products. At the optimal PS-MS conditions, the calibration curves of bisphenols in the range of 1-100 μg/mL were linear. The correlation coefficients were higher than 0.998, and the LODs of the target compounds were 0.1-0.3 μg/mL. After a simple treatment by dichloromethane on the surface, the samples were analyzed by PS-MS in situ for rapid screening without a traditional sample pretreatment procedure, such as powdering, extraction, and enrichment steps. The analytical time of the PS-MS method was less than 1 min. In comparison with conventional HPLC-MS/MS, it was demonstrated that PS-MS was a more effective high-throughput screening and quantitative analysis method.

The metallic 1T-MoS2 has attracted considerable attention as an effective catalyst for hydrogen evolution reactions (HERs). However, the fundamental mechanism about the catalytic activity of 1T-MoS2 and the associated phase evolution remain elusive and controversial. Herein, we prepared the most stable 1T-MoS2 by hydrothermal exfoliation of MoS2 nanosheets vertically rooted into rigid one-dimensional TiO2 nanofibers. The 1T-MoS2 can keep highly stable over one year, presenting an ideal model system for investigating the HER catalytic activities as a function of the phase evolution. Both experimental studies and theoretical calculations suggest that 1T phase can be irreversibly transformed into a more active 1T′ phase as true active sites in photocatalytic HERs, resulting in a "catalytic site self-optimization". Hydrogen atom adsorption is the major driving force for this phase transition.

Exploiting highly efficient electrocatalysts through simple methods is very critical to the development of energy conversion technologies. Herein, we develop a hierarchical reduced graphene oxide supported dealloyed platinum–copper nanoparticle catalyst (Pt–Cu/RGO) by a facile one-step electrodeposition of graphene oxide in the presence of H2PtCl6 and copper ethylenediamine tetraacetate. The nanostructure and composition were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and Raman spectroscopy. Meanwhile, the electrocatalytic performance was investigated by cyclic voltammetry and chronoamperometry, showing that the Pt–Cu/RGO catalyst not only equips with an outstanding electrocatalytic activity for the methanol oxidation reaction (2.3 times that of commercial Pt/C catalyst), but also shows a robust durability and superior tolerance to CO poisoning. The excellent electrocatalytic performance could be attributed to the three-dimensional hierarchical structure, porous dealloyed nanoparticles and synergistic effect between each component.

Transition metal phosphides (TMPs) have been one of the ideal candidates as low-cost and high-efficiency catalysts for hydrogen evolution reactions (HERs). We report herein a novel TMP architecture, Fe2P nanoparticles/reduced graphene oxide (rGO) nanosheets/Fe2P nanoparticles (Fe2P@rGO) sandwich-structured (Fe2P@rGO) nanowall arrays on a Ti plate. This nanostructure was easily prepared via one-step electrodeposition followed by a low-temperature phosphidation reaction. The Fe2P@rGO nanowall array film is featured with maximally exposed catalytic sites, fast electron and mass transport, and robust structure stability, and therefore it behaves as an excellent HER electrocatalyst. The Fe2P@rGO shows a low overpotential of 101 mV at a current density of 10 mA cm−2 and a small Tafel slope of 55.2 mV dec−1 with a large exchange current density of 0.146 mA cm−2. Furthermore, the catalyst exhibits superior durability evidenced by about 87% catalytic activity retention against about 55% for the commercial Pt/C catalyst after a 12 h test. The study presents a new nanoengineering strategy for high-performance TMP-based HER catalysts.

A ethylenediaminetetra-acetic acid (EDTA) cross-linked chitosan and N,N-methylenebis(acrylamide) (MBA) cross-linked polyacrylamide based double network hydrogel was successfully synthesized via a two-step method and then employed for heavy metal ion adsorption. Various adsorption conditions, such as pH, ionic strength, adsorbent dosage, and contact time were investigated. CTS/PAM gel have a theoretical maximum Cd(II), Cu(II), and Pb(II) sorption capacities of 86.00, 99.44, and 138.41 mg/g, respectively, at experimental conditions. The adsorption process of CTS/PAM gel on the heavy metal ion was identified to be endothermic and follows an ion-exchange reaction. The application of this gel adsorbent was demonstrated using practical industrial effluent. We found that it could effectively treat practical wastewater with all kinds of heavy metals. At an adsorbent dosage of 8 g/L, the total metal ions concentration declined from 448.5 to 5.0 mg/L. Simultaneously, the CTS/PAM gel exhibited remarkable mechanical ...

Photoelectrocatalytic (PEC) process is a rising approach to simultaneous removal of heavy metals and organic pollutants. However, electric field plays a dual role in the reduction of negatively charged metal species (e.g., Cr 2 O 7 2− ): Reduction driving force makes metal species move to cathode; electric field force pulls negatively charged species to anode. The reduction reaction of Cr(VI) (Cr 2 O 7 2− ) strongly depends on the concentration of both Cr 2 O 7 2− and H + on the surface of cathodes. The reduction of Cr(VI) in conventional PEC process must enhance proton concentration with a mass of strong acid or prolong reaction time. A highly effective PEC system was constructed with amino-modified carbon cloth as cathode and reduced graphene oxide functionalized TiO 2 nanotube arrays as photo-anode. The amino groups could concentrate protons to form quaternary ammonium cations which could adsorb Cr 2 O 7 2− ions through electrostatic interaction. The graphene functionalized anode greatly accelerated the mass transfer of organic pollutants onto photo-anode. Resultantly, Cr(VI) and 2,4-dichlorophenoxyacetic acid (2,4-D) could be removed faster at lower cell voltage compared with conventional PEC process and the electric energy consumption decreased by at least 50%. Furthermore, the proposed PEC process could be repeatedly utilized with highly stable working performance. This work would give a new insight into the development of cost-effective PEC process for treatment of Cr(VI)-containing wastewater.

Although Fe-based biochar adsorbents are attractive for removing arsenic from water due to their advantages of costing little and being producible at a large scale, the practical applications of these granular adsorbents are mainly limited by low Fe utilization and slow adsorption kinetics. In this study, iron oxide nanoneedle array-decorated biochar fibers (Fe-NN/BFs) adsorbents have been prepared through a simple hydrothermal reaction. The vertical growth of iron oxide nanoneedle arrays on the surface of biochar fibers maximizes Fe utilization and shortens As diffusion distance, thereby increasing As removal kinetics and capacity. Batch experiments show that the adsorption capacities of Fe-NN/BFs for As(V) and As(III) reach to 93.94 and 70.22 mg/g-Fe at pH 7.0, respectively. As(V) levels (275 μg/L) in groundwater are rapidly reduced (less than 5 min) to below 10 μg/L using Fe-NN/BFs (1 g/L) at pH 6.7. Similar As(III) levels can be reduced to below 10 μg/L within 30 min by Fe-NN/BFs (1.5 g/L). In fixed-bed experiments, the treatment volumes of As(V) and As(III) spiked groundwater reach to 2900 BV (26.2 L) and 2500 BV (22.6 L), respectively, using two columns packed with Fe-NN/BFs in tandem (C0 = 275 μg/L, 2 g of adsorbents in each column). When the As concentration in the influent is reduced to 50 μg/L (As(V): 25 μg/L + As(III): 25 μg/L), the treatment volume using one column reaches up to 11000 BV. The Fe-NN/BFs packed column can be easily regenerated and reused many times. After four regenerations, the treatment volume of As(V) and As(III) were reduced by 10.4% and 22.8%, respectively.

As charge storage occurs both on the surface and in the bulk of material, the dynamics of charge storage is a key issue in the practice of energy storage. Although the energy storage can be increased in the bulk of the material, it often suffers from a quite slow kinetics, which seriously hinders the rate capability. Keeping high surface-induced capacitive contribution is proposed to address this issue. Herein, a porous scaffold, TiO2 nanotube arrays grown in a Ti foil (TiO2 NTs/Ti) is selected as the current collector for electrodeposition of porous polyaniline/reduced graphene oxide (PANI/rGO) hybrid film. The capacitive contribution of PANI/rGO@TiO2/Ti is quantitatively evaluated, showing a high surface-induced capacitive contribution up to 58% at high rates (>25 mV s−1) and large electron transfer coefficient of 2. As a result, the electrode not only shows an ultrahigh specific capacity of 908 C g−1 at 1 mV s−1, but also delivers an outstanding rate capacity of 310 C g−1 at 500 mV s−1. PANI/rGO@TiO2/Ti also shows excellent cycling stability with 80% capacity retention after 10,000 cycles at a high current density of 25 A g−1.

In the study, PS/Ag composite microspheres with polystyrene (PS) core and silver shell were synthesized by ultrasonic electroless plating. The samples were characterized by SEM, FTIR and XRD. The effects of times of sensitization and silver plating, mass ratio of AgNO3 to PS microspheres and stirring method on the preparation and dispersion of PS/Ag microspheres were studied. The results show that the more times of sensitization and silver plating, the more uniform the silver deposition on the surface of microspheres. When the mass ratio of AgNO3 to PS microspheres is 2: 1, it can promote the uniform coating of silver shell and reduce the content of free silver. Ultrasonic assisted electroless plating for 10 min can prevent PS/Ag microspheres from agglomerating and improve the speed of electroless plating. The thickness of the silver shell on the surface of the PS microsphere is about 200 nm.

The optimized geometrical configuration of muitiple active materials into hierarchical nanoarchitecture is essential for the creation of photocatalytic degradation system that can mimic natural photosynthesis. A bamboo-like architecture, CuO nanosheets and Ag nanoparticles co-decorated TiO2 nanotube arrays (Ag/CuO/TiO2), was fabricated by using simple solution-immersion and electrodeposition process. Under simulated solar light irradiation, the 2,4-dinitrophenol (2,4-DNP) photocatalytic degradation rate over Ag/CuO/TiO2 was about 2.0, 1.5 and 1.2 times that over TiO2 nanotubes, CuO/TiO2 and Ag/TiO2, respectively. The enhanced photocatalytic activity of ternary Ag/CuO/TiO2 photocatalyst was ascribed to improved light absorption, reduced carrier recombination and more exposed active sites. Moreover, the excellent stability and reliability of the Ag/CuO/TiO2 photocatalyst demonstrated a promising application for organic pollutant removal from water.

A Gram-stain-positive, facultatively anaerobic, short rod-shaped, oxidase-negative and non-motile novel strain, designated YIM 101505T, was isolated from the faeces of a primate, Assamese macaque, and was studied to determine its taxonomic position. The cell wall contained meso-diaminopimelic acid and short-chain mycolic acids. Whole cell sugars were mannose, galactose and arabinose as major components. The major fatty acids (>10 %) were C18 : 1 ω9c, C16 : 0 and C17 : 1 ω8c and the major menaquinone was MK-9(H2). The polar lipids included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside, glycolipid and six unidentified lipids. The new isolate shared most of the typical chemotaxonomic characteristics of members of the genus Corynebacterium . The closest related species was Corynebacterium efficiens based on 16S rRNA gene (98.1 % similarity) and partial rpoB gene (91.4 % similarity) sequences. Similarities with other species of this genus were below 97 % based on the 16S rRNA gene. The DNA–DNA hybridization value between YIM 101505T and C. efficiens DSM 44549T was 47.7±3.6 %. Moreover, the physiological and biochemical characteristics of YIM 101505T and C. efficiens DSM 44549T were different. Thus, strain YIM 101505T is considered to represent a novel member of the genus Corynebacterium , for which the name Corynebacterium faecale sp. nov. is proposed. The type strain is YIM 101505T (=DSM 45971T=CCTCC AB 2013226T).

In this paper, g-C3N4/GR hybrid has been prepared by a novel one-step electrochemical reduction technology for the first time. GR not only serves as immobilization platform for g-C3N4, but also significantly enhances the electrochemiluminescence (ECL) signal of g-C3N4 (∼4.7 times); additionally, the ECL signal can be further enhanced in the presence of the self-produced coreactant from oxygen reduction. Moreover, due to the quenching effect of pentachlorophenol (PCP) on the ECL signal of g-C3N4/GR, an advanced ECL sensor based on g-C3N4/GR has been fabricated for the ultrasensitive and rapid detection of PCP with unprecedented sensitivity reaching 1.0 × 10−11 mol L−1 in a wide linear range from 1.0 × 10−11 to 1.0 × 10−7 mol L−1, and the possible ECL detection mechanism has been proposed in detail. The practicability of the sensing platform in real water sample shows ideal recovery rates. Moreover, we also find that the one-step electrodeposition technology might be a good and viable way to make the bulk g-C3N4 thinner. Our experiments display the powerful utility of GR to g-C3N4 ECL studies and will emerge eximious applications in analytical communities and environmental monitoring.

Nitrogen-rich carbon material derived from carbon self-repairing g-C3N4 is self-assembled with graphene oxide (GO) to form a porous structure. Different from the pristine g-C3N4, which has scarcely been employed in supercapacitors because of its low charge mobility, the carbon self-repairing g-C3N4 (C-C3N4) shows an improved electrochemical activity. After carbon-repairing, a delocalized big π-bond can be formed by the homogeneous C-substitution for N atoms or the formation of new interstitial C–N bond. The extending π-conjugation planar layer of C-C3N4 possesses a closer contact with GO to form a three-dimensional (3D) pore structure, which ensures good mobility for electrons and quick access for electrolytes. Under the optimum C-repairing content of 5.99 at%, the C-C3N4@rGO exhibited high specific capacity of 379.7 F g−1 and energy density of 52.7 W h kg−1 at a current density of 0.25 A g−1. Moreover, the electrode kept 85% capacity retention after 10 000 cycles at a high constant current density of 10 A g−1. The active sites of pseudocapacitance can be confirmed in the oxygen-containing groups and the carbon atoms close to the nitrogen by the XPS results.

A highly stable and effective electrochemiluminescence (ECL) sensing platform of copper oxide nanowires coupled with reduced graphene oxide (CuO NWs/rGO) is presented for ultrasensitive detection of pentachlorophenol (PCP). The CuO NWs/rGO sensing system is prepared via an electrodeposition technique followed by chemical oxidation and annealing processes. The CuO nanowire is revealed to be electroluminescent for the first time, and the rGO greatly enhances the ECL signal. In the presence of the coreactant S 2 O 8 2− , the CuO NWs/rGO-based ECL sensor can sensitively and selectively detect PCP with a wide linear range from 1.0 × 10 −14 to 1.0 × 10 −9 mol L −1 and a very low detection limit of 0.7 × 10 −14 mol L −1 . The sensor shows excellent recyclability and outstanding durability evidenced by its nearly unchanged ECL signal after the sensing electrode being stored for 10 months in air at room temperature. The proposed ECL sensor could be a promising alternative method for the emergency and routine monitoring of the PCP in real environment.

Three-dimensional (3D) network-like graphitic carbon nitride nanobelts (g-C3N4 NBs) were facilely achieved by the hydrothermal treatment of bulk g-C3N4 in a medium strong oxalic acid solution (1 M, pH 0.89). The positions of the conduction band (CB) and valence band (VB) were upraised from −0.90 and +1.86 eV for bulk g-C3N4 to −0.92 and +1.92 eV for g-C3N4 NB networks with enhanced redox ability, respectively. With an optimized Pt loading of 3%, the g-C3N4 NB networks showed excellent visible-light photocatalytic H2 production activity (1360 μmol g−1 h−1), which was 10.9 times higher than that of optimized 2% Pt@bulk g-C3N4 (124.7 μmol g−1 h−1) using triethanolamine as a sacrificial agent. Furthermore, Pt@g-C3N4 NBs exhibited a considerable rate of H2 evolution of 33.3 μmol g−1 h−1, much higher than 1.79 μmol g−1 h−1 for Pt@bulk g-C3N4 in distilled water without any sacrificial agents, revealing a great potential for photocatalytic overall water splitting. This outstanding performance not only originates from its unique 3D nanostructure and prolonged electron lifetime, but also from the electronic structure modulation and improved redox capacities of the CB and VB. The pH effect of hydrothermal conditions on the g-C3N4 molecular structure, chemical elements, optical properties and catalytic performance is also expounded. This study demonstrates a facile and environmentally friendly strategy to design highly efficient g-C3N4 catalysts for potential applications in solar energy driven photocatalytic water splitting.

We report a nearly vertical reduced graphene oxide (VrGO) nanosheet coupled with polyaniline (PANI) for supporting palladium (Pd) nanoparticles. The PANI-coupled VrGO (PANI@VrGO) nanosheet is prepared by a simple one-step electrodeposition technique ,and Pd nanoparticles are anchored on the support of PANI@VrGO through the spontaneous redox reaction of PANI with a palladium salt. The designed PANI@VrGO nanosheet efficiently exposes the surface of rGO sheets and stabilizes metal nanoparticles. Consequently, the Pd/PANI@VrGO electrocatalyst exhibits high catalytic activity and excellent durability for alcohol oxidation reaction. The proposed nanoarchitecture offers a new pathway to greatly promote the performances of rGO in various applications; moreover, this work provides a powerful and universal synthetic strategy for such an architecture.

Photoelectrocatalytic (PEC) especially continuous flow PEC process for organic wastewater treatment greatly depends on both catalytic capacity and practical availability of electrode materials. In this study, g-C3N4 nanosheets are implanted into TiO2 nanotube arrays mesh (TCNs) through direct calcination of TiO2 nanotube array mesh loading melamine precursor. The TCNs photoelectrodes exhibit excellent PEC activity in organic pollutant degradation. Typically, almost 100% of tetracycline (TC, an emerging refractory antibiotic pollutant) is removed in 2 h and TOC removal reaches to 93% in 3 h under simulated solar irradiation at 1 V vs. Ag/AgCl. Theoretical calculations are performed to predict the primary reactive sites for radical species attack and the intermediates are identified. Meanwhile, the ecotoxicity of TC-containing wastewater greatly decrease after PEC treatment. Impressively, because of the mesh screen effect and high catalytic capacity of the photoelectrode, continuous flow PEC process keeps 80% removal efficiency of TC in real wastewater in the absence of additional background electrolyte. After prolonging 20 h, the level of treatment is highly stable. This work would set an example for potential large-scale treatment of organic wastewater using PEC process.

Six new metabolites, actinofuranones D-I (compounds 1&ndash, 6), were isolated together with three known compounds&mdash, JBIR-108 (7), E-975 (8), and E-492 (9)&mdash, from a fermentation broth of Streptomyces gramineus derived from the lichen Leptogium trichophorum. The structures of the new compounds 1&ndash, 6 were established using comprehensive NMR spectroscopic data analysis, as well as UV, IR, and MS data. The anti-inflammatory activity of these isolated compounds were evaluated by examining their ability to inhibit nitric oxide (NO) production in LPS-stimulated RAW 264.7 macrophage cells. Compounds 4, 5, 8, and 9 attenuated the production of NO due to the suppression of the expression of nitric oxide synthase (iNOS) in LPS-induced RAW 264.7 cells. Moreover, 4, 5, 8, and 9 also inhibited LPS-induced release of proinflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor &alpha, (TNF-&alpha, ).

Although aptamer has been demonstrated as an important probe for antibiotic determination, the selective sensing of different antibiotics is still a challenge due to their structure similarities and wide folding degrees of aptamer. Herein, a field-effect transistor using MoS2 nanosheet as the channel and an aptamer DNA (APT) with its configuration shaped by a complementary strand DNA (CS) is employed for kanamycin (KAN) determination. This probe structure contributes to an enhanced selectivity and reliability with reduced device-to-device variations. This MoS2/APT/CS sensor shows time-dependent performance in antibiotic sensing. Prolonged detection time (20 s–300 s) leads to an enhanced sensitivity (1.85–4.43 M-1) and a lower limit of detection (1.06–0.66 nM), while a shorter detection time leads to a broader linear working range. A new sensing mechanism relying on charge release from probe is proposed, which is based on the “replacement reaction” between KAN and APT-CS. This sensor exhibits an extremely high selectivity (selectivity coefficient of 12.8) to kanamycin over other antibiotics including streptomycin, tobramycin, amoxicillin, ciprofloxacin and chloramphenicol. This work demonstrates the merits of probe engineering in label-free antibiotic detection with FET sensor, which presents significant promises in sensitive and selective chemical and biological sensing.

Low cost, high adsorptivity, fast regeneration and excellent reusability are strongly recommended for a qualified adsorbent used in removing heavy metals from practical wastewater. A sponge-like polysiloxane-graphene oxide (PS-GO) gel adsorbent for removing lead and cadmium from wastewater has been prepared by simple one-step sol-gel method. The maximum sorption capacity of Pb(II) achieves as high as 256 mg/g. PS-GO gel adsorbent exhibits an excellent reusability because of its remarkable mechanical strength and highly efficient desorption/regeneration. In the static treatment process, after five cycles, Pb(II) in actual industrial effluent at 3.225 mg/L could be reduced to below 0.01 mg/L, still holding over 99% removal efficiency. Significantly, in the dynamic treatment process using a fixed-bed column packed with PS-GO gel, the treatment volume of wastewater is as high as 720 bed volume (BV) (8143 mL) for Pb(II) and 480 BV (5429 mL) for Cd(II) with producing only 11.31 mL eluent in each cycle. It should be stressed that the in situ regeneration of PS-GO gel adsorbent in fixed-bed column is operationally feasible and the treatment technology has the advantage of producing “zero” amount of sludge. This work has taken a key step closer to the treatment of actual heavy metals wastewater based on adsorption technology in large scale.

Highly efficient and non-hysteresis organic/perovskite planar heterojunction solar cells was fabricated by low-temperature, solution-processed method with a structure of ITO/PEDOT:PSS/CH 3 NH 3 PbI 3 /PCBM/Al. The high-quality perovskite thin film was obtained using a solvent-induced-fast-crystallization deposition involving spin-coating the CH 3 NH 3 PbI 3 solution followed by top-dropping chlorobenzene with an accurate control to induce the crystallization, which results in highly crystalline, pinhole-free, and smooth perovskite thin film. Furthermore, it was found that the molar ratio of CH 3 NH 3 I to PbI 2 greatly influence the properties of CH 3 NH 3 PbI 3 film and the device performance. The equimolar or excess PbI 2 was facile to form a flat CH 3 NH 3 PbI 3 film and produced relatively uniform perovskite crystals. Perovskite solar cells (PSCs) with high-quality CH 3 NH 3 PbI 3 thin film showed good performance and excellent repeatability. The power conversion efficiency ( PCE ) up to 13.49% was achieved, which is one of the highest PCEs obtained for low-temperature, solution-processed planar perovskite solar cells based on the structure ITO/PEDOT:PSS/CH 3 NH 3 PbI 3 /PC 61 BM/Al. More importantly, PSCs fabricated using this method didn’t show obvious hysteresis under different scan direction and speed.

A poly(sodium acrylate)–graphene oxide (PSA–GO) double network hydrogel adsorbent was facilely prepared in mild conditions. The chemical composition of the hydrogel adsorbent was characterized by FITR, Raman spectra and XPS analysis. The uniaxial compression tests proved extraordinary mechanical strength of PSA–GO gel, benefiting to practical application. The PSA–GO hydrogel was used as an adsorbent for heavy metal ions such as Cd(II) and Mn(II). The adsorption behaviors in different conditions (e.g., pH, contact time, ionic concentration and existence of fulvic acid) as well as the adsorption mechanism were studied. The maximum sorption capacities were found up to 238.3 mg/g and 165.5 mg/g at pH = 6 and T = 303 K, for Cd(II) and Mn(II), respectively, estimating from the Langmuir model. After experiencing four cycles, this adsorbent kept high removal efficiencies of Cd(II) and Mn(II), indicating a good reusability. Cost analysis reveals that the adsorbent is relatively low-cost. Meanwhile, its satisfactory performance in practical industrial effluent test demonstrates that PSA–GO gel can be a potential candidate for practical application.