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Packed open-cell foams are proposed as an alternative to standard packed bed configuration commonly adopted for the adsorption columns of a temperature swing adsorption process. In this contribution, heat transfer in an adsorption column with a packed foam configuration is investigated by experimental and modeling analysis, in comparison to a standard packed bed. The introduction of the packed foam allows for more rapid temperature transitions and substantial reduction of temperature gradients within the adsorption bed. The impact of this heat transfer enhancement on the separation performance of a temperature swing adsorption process is evaluated by modeling an example post-combustion CO2 capture application. Although the presence of the foam implies a loss of sorbent inventory (-26.5%), higher process productivity (+80%) is achieved thanks to faster temperature swings and more homogeneous temperature distribution within the adsorption columns., Chemical Engineering Journal, 430 (3), ISSN:0300-9467, ISSN:1385-8947, ISSN:1873-3212, ISSN:0923-0467

Increasing the separation efficiency of photogenerated carriers and preventing the hydrogen back oxidation are two key challenges in photocatalytic hydrogen production. Herein, we report a promising PtO@Ti3C2/TiO2 photocatalyst to overcome these two challenges by in-situ growing TiO2 nanosheets on Ti3C2 MXene (to improve charge separation) and depositing PtO nanodots (to diminish hydrogen back reaction) for enhanced photocatalytic hydrogen production. Within this design principle, the photogenerated electrons and holes in the PtO@Ti3C2/TiO2 composites flow in opposite direction into PtO and Ti3C2 respectively, resulting in effective separation of the photogenerated electrons and holes. Beyond, the higher oxidation state of PtO nanodots also largely suppresses the undesirable hydrogen back oxidation reaction. Thereby the PtO@Ti3C2/TiO2 composite demonstrates remarkable hydrogen production efficiency. Our work here indicates that rational design of dual co-catalysts could not only promote the separation of photogenerated carriers for enhanced hydrogen production, but also inhibit the reverse reaction of hydrogen production.

Highlights • Daily moments of COVID19 cases reveal consistent scaling from 10 km to 2600 km. • COVID19 cases are found to have multi-scaling with a multifractality kernel. • The spatial correlation of infections approach that of the underlying population. • Re-opening urban centers affects spread and evolution of the disease for months., The spatial template over which COVID-19 infections operate is a result of nested societal decisions involving complex political and epidemiological processes at a broad range of spatial scales. It is characterized by ‘hotspots’ of high infections interspersed within regions where infections are sporadic to absent. In this work, the sparseness of COVID-19 infections and their time variations were analyzed across the US at scales ranging from 10 km (county scale) to 2600 km (continental scale). It was found that COVID-19 cases are multi-scaling with a multifractality kernel that monotonically approached that of the underlying population. The spatial correlation of infections between counties increased rapidly in March 2020; that rise continued but at a slower pace subsequently, trending towards the spatial correlation of the population agglomeration. This shows that the disease had already spread across the USA in early March such that travel restriction thereafter (starting on March 15th 2020) had minor impact on the subsequent spatial propagation of COVID-19. The ramifications of targeted interventions on spatial patterns of new infections were explored using the epidemiological susceptible-infectious-recovered (SIR) model mapped onto the population agglomeration template. These revealed that re-opening rural areas would have a smaller impact on the spread and evolution of the disease than re-opening urban (dense) centers which would disturb the system for months. This study provided a novel way for interpreting the spatial spread of COVID-19, along with a practical approach (multifractals/SIR/spectral slope) that could be employed to capture the variability and intermittency at all scales while maintaining the spatial structure.

In this work an experimental proof-of-concept of the Ca-Cu process has been carried out. The Ca-Cu process combines sorption-enhanced steam reforming of methane with a Ca-based sorbent with chemical looping of a Cu-based oxygen carrier to provide the energy for the sorbent regeneration. Each process step has been studied separately for different operating pressures and inlet gas compositions, and addition complete cycles (including all three consecutive process steps, viz. the sorption-enhanced reforming step, oxidation step and regeneration step) have been performed to evaluate the technical feasibility of the complete process. The pressure influences the sorption-enhanced reforming step negatively, while the steam-to-carbon ratio does not influence the average outlet H2 (dry) fraction. When increasing the inlet O2 concentration during the oxidation step, the amount of CO2 released increases, whereas increasing the pressure decreases the amount of CO2 released. In the regeneration step, increasing the H2 fraction in the feed increases the amount of sorbent that is regenerated, reaching 70 wt% of the sorbent in the bed with 60 vol% H2 in the feed. More than 285 complete cycles were performed, the solids were still chemically performing well, and the results were still reproducible. Simulations with a pseudo-homogeneous reactor model were performed for all the separate steps. The model does not describe the experimental data well, which was attributed to problems with the packing of the bed at the bottom of the reactor (solids maldistribution), which was confirmed after opening the reactor after the experimental campaign. The problems with the packing of the bed was caused by problems with the chemical–mechanical stability of the oxygen carrier, which became a powder after the experiments due to the high mechanical stresses it was exposed to.

A TiO2 nanosheets constructed yolk-shell architecture with tunable inner voids is designed and prepared as sulfur host for high-performance and ultralong-life Li-S battery. With the integration of TiO2 nanosheets to form yolk-shell sulfur-TiO2 (S@void@TiO2) architecture with controllable inner voids, the S@void@TiO2 composite with optimized inner voids provides sufficient contacting sites to improve the utilization of insulating sulfur and allows sulfur to freely expand without destroying the electrode. In particular, the density functional theory (DFT) calculations from molecular level reveal that the hybridization of Li 1s, S 2p and O 2p orbitals ensures the effective chemisorption between polysulfides and TiO2 with long-term cycling stability. Consequently, the optimized S@void@TiO2 electrode maintains a capacity of 766 mAhg−1 after 1000 cycles at 0.2C. Even at 2C for 400 cycles, the capacity still retains at 511 mAhg−1, representing the best results of TiO2-based nanostructures for Li-S batteries. This work illustrates that carefully design novel yolk-shell structure is important to address the shortages of sulfur-based cathodes for advanced Li-S battery.

Simultaneous detection of multiple types of microRNA (miRNA) is of great significance in early cancer diagnosis. In this study, rare-earth-doped CaF2 upconversion nanocrystals (CaF2: RE3+, namely Ho3+ or Tm3+ and Yb3+) are formed within the mesopores of silica nanoparticles (CaF2: RE3+@MSN), in an in-situ manner, by capillary effect and thermo-decomposition method. Comparing to current upconversion nanoparticles, the amorphous and mesoporous nature of CaF2: RE3+@MSN provides abundant active groups and high specific surface area for feasibly immobilizing oligonucleotide probe. The simultaneous and selective detection of multiple miRNAs was achieved based on the photoluminescence spectra of different CaF2: RE3+@MSN conjugated with DNA probes in the same solution. The results indicated that the proposed approach holds significant potential for multiple miRNA detection and offers an opportunity for cancer early diagnosis.

Triple negative breast cancer (TNBC) is the most fatal subtype among all other types of breast cancer and there are no targeted chemotherapy for the treatment of TNBC due to the absence of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (HER-2). To address this problem, we develop a targeted non-viral vector which could efficiently deliver the gene of interest and could also diagnose of TNBC. We have synthesized carbon quantum dots (CD) from sweet lemon peel, conjugated it with different generation of polyamidoamine (PAMAM) dendrimers to get CD-PAMAM conjugates (CDPs). RGDS peptide was further conjugated to CDP to target α v β 3 integrin which is over expressed in TNBC. DNA complexation assay, cellular cytotoxicity, hemolysis assay, DNase I assay, cellular uptake and in vitro transfection showed CDP3 as a promising gene carrier system TNBC gene therapy. Besides, CDP3 shows selective quenching of fluorescence in presences of Cu(II) with a quenching efficiency of about 93%. As the Cu(II) ion concentration remains upregulated in TNBC, CDP3 could be a promising theranostic tool for TNBC treatment.

New results of endothermic dehydration of undiluted ethanol on alumina catalyst in pilot wall-heated tubular reactor are presented. Activity and physicochemical characteristics of the proprietary acid-modified alumina (AMA) prepared by gibbsite flash calcination in TSEFLAR™ reactor were compared to the properties of commercially available alumina samples prepared by precipitation (CS1) or flash calcination of gibbsite in a flue gas (CS2). The samples differed in phase composition, which corresponds to γ-Al2O3 in CS1, mixed γ- and χ-Al2O3 in AMA and CS2; sodium content and concentration of Lewis acid sites (LAS) were different as well. Acid modification resulted in AMA catalyst with improved acidic properties and catalytic activity higher than that of CS2, despite the lower sodium content in the latter. Ethanol-to-ethylene dehydration in the wall-heated tubular reactor proceeded at the catalyst bed temperatures mainly below 385 °C, where AMA catalyst is the most active due to the highest content of strong LAS. The heat-agent temperature favors yield of ethylene rather than that of by-products. Higher linear velocity and porosity contribute to a flatter axial temperature profile in the bed; a higher average integral temperature gives a quantitative estimate. This ensures higher ethylene yield with a lower ethanol consumption even at a reduced heat-agent temperature. On the ring-shaped AMA catalyst, the greater ethylene yield, catalyst productivity and sharply reduced hydraulic resistance are reached compared to CS2 cylinders. For the first time we showed that use of AMA ring-shaped catalyst in wall-heated tubular reactor in contrast to the SynDol alumina based catalyst in adiabatic reactor can improve the catalyst productivity by 5–8 times and WHSV by 5–12 times.

The successful treatment of gliomas relies on two important factors, namely therapeutic genes/drugs and efficient delivery vehicles to cross the blood-brain barrier. In this work, a new gene vector was constructed based on polycaprolactone (PCL), glutathione (reduced; GSH)-sensitive polyethylenimine (PEI-SS) and polyethylene glycol (PEG), and modified with a cell-penetrating peptide (tLyp-1); this yielded tLyp-1-conjugated GSH-sensitive biodegradable micelles (PPPt) that mediated enhanced tumour necrosis factor (TNF)-related apoptosis-inducing ligand (pUNO1-hTRAILa) and curcumin (CUR) co-delivery to gliomas. The sensitisation function of CUR was used to explore whether CUR and genes have a synergistic antitumour effect. The results showed that the drug loading efficiency of PPPt was about 8.6%. The PPPt possessed good cytocompatibility and blood compatibility when the concentration was less than 0.06 mg/mL. PPPt strongly condensed pUNO1-hTRAILa to form a nanocomplex and efficiently transfected C6 cells. The drug-release behaviour of PPPt/CUR/pUNO1-hTRAILa was reduction-sensitive and the cellular uptake results indicate that modification of tLyp-1 promoted the internalisation of micelles. The PPPt/CUR/pUNO1-hTRAILa complexes exhibited much better in vitro and in vivo antitumour effects than micelles loaded with CUR or pUNO1-hTRAILa alone. We also used magnetic resonance imaging for in vivo monitoring of the transcranial drug delivery and therapeutic effect of the tumour on rats bearing in situ glioma.

Effective surface passive cooling and superhydrophobicity is vital for promoting more flexible application of energy power system for aircraft and aerospace. Here, we experimentally demonstrate a fractal-patterned coating on TA15 titanium alloy for superhydrophobic and passive cooling performance through plasma electrolytic oxidation and hydrothermal treatment successively. The coating exhibits excellent corrosion resistance and self-cleaning properties, largely thanks to the fractal structure and low surface energy. Additionally, the micro-hole’s infrared trapping effect and TiO2 lattice absorption significantly increase the emissivity over the thermal wavelength range. When functioned on a titanium radiator, such a coating can reduce the temperature by as much as 9.3 °C. Therefore, the passive heat dissipation and superhydrophobic multi-functional coatings are expected to be a promising candidate for heat exchange equipment that requires exposure to harsh external environments.

Li4SiO4-based ceramic has been considered as one of the most promising candidates for high-temperature CO2 capture owing to its relatively high sorption capacity and desirable cyclic stability. Si-source is one of the most important factors affecting the cost as well as the CO2 capture performance of Li4SiO4 sorbent. In this work, naturally occurring wollastonite was firstly employed as the Si-source to produce Li4SiO4-based sorbent. The as-prepared sorbent was primarily composed of Li4SiO4 and CaO. It is believed that the enhanced CO2 capture performance was attributed to the effect of CaO as well as the occurrence of Li-Ca interactions ( L i 4 S i O 4 + C a O + C O 2 ↔ L i 2 C a S i O 4 + L i 2 C O 3 ), which were experimentally verified via in situ XRD test. As a result, the sorbent possesses a relative high capacity of ∼0.18 g/g at the initial cycles during the cyclic sorption-desorption test. However, its capacity gradually declined owing to the separation and formation of sintered CaO external shell. From the cost analysis, the as-prepared CaO-Li4SiO4 sorbent can effectively decrease the total raw material cost by reducing Li-demand. To sum up, the good comprehensive performance and relative low cost of as-prepared CaO-Li4SiO4 sorbent make it promising for its practical applications in the future.

In this work, a series of BiOBr/MIL-53(Fe) hybrid photocatalysts have prepared by a facile co-precipitation method. Rhodamine B (RhB) and carbamazepine (CBZ) were selected as the targets to evaluate the visible-light photocatalytic activity of the prepared samples. All of the hybrids exhibited better catalytic performance compared to the pristine BiOBr, and the performance of BiOBr/MIL-53 (with 20 wt% of MIL-53) was the most efficient. The excellent performance can be contributed to the incorporation of MIL-53(Fe) which not only form the heterojunction with BiOBr to inhibit the recombination of the photoinduced electron-hole pairs, but also utilize the visible light more effectively. The photocatalytic mechanism was studied, it shows that OH and h+ were both the main active species for the degradation of contaminants. Moreover, the degradation pathways of CBZ via the photocatalysis over BiOBr/MIL-53(Fe) hybrid were presented based on the determination of LC–MS/MS and the results of catalytic mechanisms. With the recent increase in reported MOFs materials, we believe a new class of hybrid catalytic materials is possible. This result is conceptually interesting as it opens the door to various MOF-based BiOBr materials for environmental purification and restoration.

Sulfamethazine (SMT) is extensively used as growth promoters and antibacterial drugs. In this study, premagnetized Fe0 was used to catalyze H2O2 decomposition (pre-Fe0/H2O2) in the presence of nitrilotriacetic acid (NTA) to remove SMT at neutral pH conditions. In all, 30.3% and 99.8% of SMT were removed by the pre-Fe0/H2O2 process (60 min) and the pre-Fe0-NTA/H2O2 process (30 min), respectively. The removal rate of SMT in the pre-Fe0-NTA/H2O2 process was 2.5 times larger than that in the Fe0-NTA/H2O2 process. Electron paramagnetic resonance signals indicated that more radicals were generated in the pre-Fe0-NTA/H2O2 system. SMT and NTA and their degradation by-products adsorbed on pre-Fe0 reduced the contact angle of the particle and prevented the formation of Fe3O4 on the particle surface, thus accelerating Fe0 corrosion. Tafel scan images confirmed the enhancement of Fe0 corrosion in the presence of NTA and magnetic field. The Fe0 corrosion rate (109) after 20 min of reaction was 6.61 cm/s in pre-Fe0-NTA/H2O2, much higher than that in Fe0/H2O2 (0.73 cm/s), pre-Fe0/H2O2 (1.47 cm/s) and Fe0-NTA/H2O2 (2.94 cm/s). Pre-Fe0-NTA/H2O2 could also keep the fast SMT removal with eight consecutive runs without the addition of pre-Fe0 and NTA and presented high efficiency for SMT removal in real municipal wastewater.

A broad ranging study of the fluid flow in packed beds of uniform diameter spheres has been implemented by the method of numerical simulation. The parametric extent of the present study encompassed both laminar and turbulent flows, random and regular packings of the spheres, bed containments in both rectangular ducts and circular pipes, and beds of either bounded or unbounded lateral extent. The regular packings included body-centered cubic, face-centered cubic, and simple cubic. Comparisons were made between the simulation-based results and relevant experimental data using variables that emerged from the experimental correlations. In particular, the Reynolds number range of the Ergun flow regime for packed beds of unbounded extent was identified. In addition, for random packed beds of bounded extent, very good agreement between the predicted and experimentally determined friction factors was found to exist. The level of agreement was sufficiently good to validate the simulation model and its implementation. The pressure drop-fluid flow results are presented in terms of friction factor-Reynolds number relationships. These dimensionless quantities were defined in terms of physical variables commonly used throughout the packed-bed literature.

The oriented external electric field (OEEF) promoted phase transfer catalysis (PTC) reaction is reported for the first time. It was demonstrated experimentally that an OEEF can act as promoter or inhibitor for the phase transfer hydrogenation of acetophenone depending on its direction. Organic solvents showed differing influences on the reaction, attributed to different electrical conductivities. A non-linear dependence of product yield on OEEF potential was also discovered. This work presents a methodology for promoting PTC reactions in the absence of a chemical phase transfer agent and shows promise for significantly improving the performance of organic reactions in biphasic liquid systems.

Fluorescent carbon dots (CDs) are drawing increasing attention due to their excellent properties, however, CDs usually show excitation-dependent emission property. Herein, we prepared a series of multi-excitation and single color emission carbon dots doped with nitrogen and silicon (SiN-CDs) by one-pot hydrothermal method from a hyperbranched polysiloxane. Interestingly, the synthesized SiN-CDs have three excitation bands at around 240, 300 and 360 nm, and only one emission band at around 440 nm. Meanwhile, SiN-CDs emit single color light in a wide excitation range and different concentrations. Structural and optical property characterizations show that the multi-excitation and single color emission property of SiN-CDs is caused by the cooperation of the sp2 carbon core with the abundant fluorescent groups on the surface. In particular, SiN-CDs have multiple functions, not only can be internalized into live cells with obvious accumulation in cell nuclei, but also possess high selectivity, sensitivity and anti-interference ability in detecting of Fe3+.

Photocatalysis or coagulation process has been separately studied for the removal of natural organic matter (NOM) from surface water, and the reaction mechanism of organic fractionations of treated effluent has been clarified. Although coagulation-based process has been extensively studied for NOM removal, few attempts have been made based on a combined process that can not only efficiently degrade NOM, but also enhance the coagulation performance. The hypothesis is that a combination of photocatalysis and coagulation process in a single unit might potentially enhance NOM removal efficiency. This is because the nano-photocatalyst can serve as both pre-oxidant and flocculation core. Herein, a combined process of visible light photocatalysis prior to coagulation is conducted, with the transformation efficiency of the organics fractionations revealed. The as-prepared nano-sized photocatalyst consisting of Bi2O3-TiO2 (molar Bi/Ti ratio 0.04:1) had a stronger visible light absorption ability. Compared to coagulation alone, the combined photocatalysis-coagulation process greatly improved NOM removal, with synergistic effect, while the pre-photocatalysis reduced the required dosage of polyaluminium chloride (PACl) coagulant and increased the optimal pH of solution. A mathematical model optimized by response surface methodology of the combined process was developed that produced a good correlation between predicted and experimental values. The optimal conditions were calculated as follow: 2.0 g/L photocatalyst, a photocatalytic reaction time of 10 min 18 sec, 0.04 mM PACl coagulant, and a pH of 4.2. These conditions particularly enhanced removal of acidic hydrophobic substance, humic-/protein-like substances and fractions with molecular weight between 3 and 44 kDa. The XRD spectra and SEM images of the produced flocs identified that these flocs consisted of a core of photocatalyst, which could contribute to an effective flocculation and enhanced NOM removal.

Effects of molecular weight (MW), charge density (CD) and structure of polyacrylamide (PAM) on conditioning of excess sludge (ES) and ozonized sludge (OS) with/without ferric salt pretreatment (FSP) were investigated by orthogonal experiment. Rheological and morphological analyses were conducted to elucidate conditioning mechanism of ES and OS. OS had smaller particle size, worse filterability, lower flowability and more evident thixotropy than ES, and required FSP before conditioning. Orthogonal experiment showed that the optimal conditioner was PAM with medium MW and cross-linked structure for ES, and high MW and linear structure for OS after FSP, respectively. The specific resistance of filtration and capillary suction time were reduced to (1.2 ± 0.1) × 1012 m/kg and 25.8 ± 1.9 s for OS after FSP and optimized PAM conditioning, and particle size increased from 30.3 for OS to 269.7 μm after conditioning. The limiting viscosity, structural strength and thixotropy of conditioned OS were lower than conditioned ES, but greatly enhanced by FSP. Morphological analyses confirmed that ozonation cracked microbial cells of sludge, and FSP obtained more porous structure and reinforced floc strength of PAM conditioned OS.

Focusing on tubular reactors with continuously distributed side injections, a general procedure to evaluate the operating mode able to reproduce the performance of a given semi-batch reactor is worked out. Namely, such operating mode is expressed as axial profiles of feed flowrate and temperature of the cooling/heating medium inside the reactor jacket. This transformation procedure, previously limited to isothermal reactors, is extended here to non-isothermal systems. The process performance (selectivity and conversion) of the original discontinuous reactor are fully reproduced using the continuous intensified reactor, while its productivity remains a degree of freedom. Notably, like in the isothermal case, the transformation procedure is kinetics-free, i.e. the knowledge of the reaction kinetics is not a precondition. As case study, a copolymerisation reaction is considered to demonstrate the potential of the method. Even though any SBR feed policy could be considered when applying this methodology, the optimal feed policy of the semi-batch reactor evaluated according to the so-called “power feed” procedure is examined considering the reactor non-isothermal. Afterwards, the proposed transformation method is applied and the performance of the two systems, discontinuous and continuous, are comparatively evaluated. Finally, given the practical difficulties associated with continuously distributed side injections, a discretisation approach is proposed based on the use of discrete lateral feeds and more realistic reactor configurations.

Spent adsorbents from the S-Zorb technology are hazardous wastes. Reactivating and recycling the spent S-Zorb adsorbents is of great significance to environmental protection. However, no report concerning this subject has been found yet. Herein, we have developed an acid-base coupling method to reactivate the spent S-Zorb adsorbents. To achieve this goal, the deactivation factors of the adsorbents were studied. The results show that the formation of Zn2SiO4 phase, which results in loss of active phase (ZnO) for sulfur storage, is the main deactivation factor. The acid-base coupling method can transform Zn2SiO4 into soluble Zn2+ via nitric acid, followed by precipitation as Zn(OH)2 with sodium hydroxide addition. After calcination, the loss of ZnO can be supplemented. The newly formed ZnO bears a willow-leaf shape that is remarkably different from the original one. Also, it has smaller particle size compared to that of fresh adsorbents. Of note is that mesopores and Lewis acid sites are created over the adsorbents via the acid-base coupling method, accelerating the mass transfer and conversion of sulfur compounds. Carbon deposited over the adsorbent surface is removed and metal sulfides (ZnS and NiS) are oxidized into metal oxides (ZnO and NiO) via calcination of the spent adsorbents. The desulfurization efficiency of the reactivated adsorbent is superior to that of the regenerated adsorbent and reaches a level comparable to that of the fresh adsorbent in gasoline desulfurization.

A novel polyacrylonitrile (PAN)-induced carbon membrane with in-situ encapsulated cobalt crystal was developed via a one-step carbonization method and applied for peroxymonosulfate (PMS) activation. The dual-function of cobalt in tuning carbon formation and activating PMS was explored. The growth mechanism of the functionalized membrane was investigated via TGA-DSC, FTIR, XRD, Raman and XPS. Results indicated that the addition of cobalt could tune the formation of C and N containing functional groups in the carbon membrane. The membrane morphologies and surface properties were further characterized by FESEM and AFM. Batch studies revealed that more than 90% of sulfamethoxazole (SMX) could be degraded after 60 min of membranes exposure in the presence of PMS. Electron paramagnetic resonance (EPR) results verified the generation of sulfate radical in this process. The removal of humic acid (HA) in a dead-end membrane filtration mode could be maintained at ∼100% with an inconspicuous sacrifice of permeate flux over 450 min. The permeate flux achieved with PMS was higher as compared to the case without PMS addition, which could be ascribed to the catalytic oxidation of organic molecules accumulated on the membrane surface. The catalytic property imports an intrinsic antifouling property of the carbon membrane in the hybrid catalytic membrane filtration process. Accepted version

Flexible all-solid-state wire-shaped supercapacitors (WSSCs) attracted tremendous attention as power sources for portable and wearable electronics. However, WSSCs usually require excellent electrochemical stability because of the complex functioning environment of wearable electronics. In this work, hierarchical porous nanoarchitectures, consisting of vertically-aligned CuO nanotube arrays/Co(OH)2 nanosheets/reduced graphene oxide composite (CuO/Co(OH)2/rGO), with high electrochemical stability were successfully prepared on Cu wires using in-situ wet-chemical approach. Co(OH)2 nanosheets were utilized to increase charge storage capacity and enlarge electroactive surface area, while supplying abundant faradic active sites. rGO deposition on the nanostructures provides an omnidirectional conductive pathway to optimize electron/ion transfer kinetics and alleviate the exfoliation and dissolution of the active materials into electrolyte. As a flexible battery-type electrode, binder-free CuO/Co(OH)2/rGO hierarchical porous nanostructures demonstrated significantly improved charge storage (22.3 mC cm−1) and excellent long-term cycling performance (with 139% retention after 10,000 cycles). Flexible all-solid-state asymmetric WSSC device matched with CuO/Co(OH)2/rGO and activated carbon (AC) electrodes exhibited wide potential window (equal to 1.45 V), high energy density and long lifetime stability (114% retention after 10,000 cycles). Moreover, flexible WSSC device demonstrated excellent mechanical stability with the charge retention of 109% at 180° bending angle. These devices could be randomly connected to achieve various current and voltage outputs, demonstrating their suitability for wearable electronics.

Heterostructured starfish-like C/CoNiO2 has been prepared by a solvothermal synthesis and was further thermally etched. Owing to the localized electron polarization and significant magnetic loss, C/CoNiO2 heterostructures with starfish-like morphology exhibited significantly enhanced electromagnetic attenuation and reflection loss. Such singularities enable this lightweight C/CoNiO2 to become an outstanding microwave absorber with wide bandwidth and strong absorption. These findings provide new insight into the possible mechanism of microwave absorption due to electron polarization and demonstrates that it is critical to improve microwave absorption performance for future applications.

In this study, N-doped porous carbons (N–doped PCs) were prepared from various biowastes by thermal annealing method under inert atmosphere and compared. Due to the differences in the textural characteristics and %w/w inorganic content, the choice of biowaste influenced the intrinsic (extent of N doping, % graphitic N) and extrinsic (specific surface area) properties of the resultant N-doped PC. The N–doped PCs were employed to activate peroxymonosulfate (PMS) for bisphenol A (BPA) removal. It was found that the N–doped PCs prepared from spent coffee ground (PC–SC) and saw dust, with higher at.% graphitic N (44–46 at.%) and specific surface area (>400 m2 g−1), performed significantly better (apparent rate constant, kapp = 0.072–0.087 min−1) than those prepared from banana peel, orange peel and dried leaves (kapp

Transition-metal dichalcogenides (TMDCs) present great potential in the area of noble metals recovery and separation. Herein, a one-pot solvothermal method was carried out to fabricate CuS nanoparticles (CuS NPs). The morphology structure and physical properties of the CuS NPs were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), N2 adsorption-desorption, and thermogravimetric analysis. Successful attempts to apply CuS NPs to the noble metal capture were firstly made. CuS NPs demonstrated highly selective binding and extremely efficient capture of Au3+, Pd2+ and Pt4+. The selectivity and capture capacity order were Au3+ > Pd2+ > Pt4+ > other metal ions. The enormous capacities for Au3+ (2.92 mmol g−1, 574.7 mg g−1), Pd2+ (1.13 mmol g−1, 222.2 mg g−1), and Pt4+ (0.72 mmol g−1, 142.9 mg g−1), and high distribution coefficients (Kd) of Au3+ (3.12 × 106 mL g−1), Pd2+ (2.24 × 106 mL g−1), and Pt4+ (6.220 × 103 mL g−1) placed the CuS NPs at the top known for such capture. Sorption isotherm of Au3+, Pd2+ and Pt4+ accorded with the Langmuir model suggesting homogeneous adsorption sites. The sorption kinetics for Au3+, Pd2+ and Pt4+ followed a pseudo-second-order model and the capture process was endothermic driven. The adsorption may occur by the reduction reaction of Au3+ and Pd2+ with CuS NPs as a captor in the hydrochloric systems, while it may occur by electrostatic interaction and electron-mediated coordination interaction for Pt4+. After the capture of noble metals, the crystallites of the CuS NPs retained the original shape, suggesting good stability and reversibility. This work proposes a new strategy to capture and recover noble metals and further expands the applications of TMDCs in pollution control.

Ag-bridged pCN/TiO2 Z-scheme heterojunction composite with faster charges separation for stimulating H2 evolution under UV and visible light in different photo-catalytic reactor systems has been investigated. The photo-catalytic activity was tested using slurry, fixed bed and monolith photo-reactor systems for continuous H2 production from glycerol-water mixture. Using slurry system, Ag-pCN/TiO2 photo-catalyst produced 470 µmol h−1 of H2 which is 8.41 and 9.66 times higher than pCN/TiO2 and pristine TiO2, respectively. The efficiency was improved due to development of heterojunction with faster charges separation, whereas, Ag provides hot photo-generated electrons by surface plasmon resonance (SPR) and active sites for H2 production. The parameters study reveals that highest H2 was obtained at pH 7, glycerol concentration of 5 wt% and 0.15 g of catalyst loading. Furthermore, by applying engineering approach Ag-pCN/TiO2 showed H2 production rate of 10150 μmol h−1 using monolith reactor, a 13.36 and 21.6 times higher than fixed-bed and slurry photoreactors. The monolith honeycomb reactor exhibited higher AQY and space yield of 49.15% and 67.67 µmol h−1 cm−3 than slurry reactor (15.77%, 3.615 µmol h-1cm−3) and fixed-bed reactor (1.63%, 3.233 µmol h-1cm−3). The superior performance of a monolith reactor was due to higher photon flux utilization, large illuminated surface area and processing volume. The schematic of conversional and Z-scheme mechanism of Ag-pCN/TiO2 were proposed based on the results. Thus, excellent performance of catalyst using monolith reactor compared to slurry and fixed-bed reactor for H2 production would offer a new opportunity of engineering approach for renewable fuels applications.

A comparison of the particle-scale PIV measurements with the corresponding particle-resolved CFD simulations in the turbulent flow regime using SST k - ω model is performed. A cylindrical packed bed containing spherical particles with the tube-to-particle diameter ratio of ∼ 4.3 operating at Re bed in the range of 1100–6600 was considered. The measured and predicted distribution of the first-order ( V x and V y ) and second-order (vorticity and strain rate) mean velocity quantities showed a reasonable agreement, which improved with the increase in the Re bed . The observed deviations were caused by the differences in the geometry (particle position and upstream packing condition) used in the CFD model compared to the measurements. On the other hand, the turbulent quantities (k and e ) were under-predicted in the simulations. However, for the e , the agreement with the measurements was found to be better at higher Re bed compared to that of the k illustrating the influence of the turbulence model on the predictions. From the results, it can be inferred that the SST k - ω turbulence model appears to be more suitable for the high-Re flows. The present work helps to establish a methodology to validate the particle-resolved CFD simulations in the turbulent flow regime.

A multi-functional, self-regenerating material was designed to adsorb and biodegrade formaldehyde from water in a simple, one-step process. The material is based on montmorillonite clay, polyethyleneimine and formaldehyde-degrading Pseudomonas putida, and has three unique functions which facilitate bioremediation: a. selectively adsorbs formaldehyde to reduce cytotoxicity, b. buffers the solution to allow efficient biodegradation, and c. self-cleans through slow release of formaldehyde and subsequent degradation by the attached bacteria, allowing regeneration and long-term use of the material. A polyethyleneimine-clay composite was optimized to carry positive surface charges and a high concentration of functional amine groups, which facilitated formaldehyde adsorption and bacterial adhesion. Formaldehyde binding was specific, yet reversible and pH dependent; binding fitted the Langmuir model and had a qmax of 62 mg·g−1 composite. A formaldehyde-degrading Pseudomonas putida strain was then immobilized on the positively charged composite through electrostatic interactions. The efficiency of the resulting bio-composite was demonstrated for multiple successive treatment cycles, with degradation rates as high as 1600 mg·L−1·FA·h−1. This self-regenerating one-step process is a promising solution to the challenging drawbacks of formaldehyde remediation and could also help design other adsorption-degradation platforms for wastewaters that demand complicated treatment strategies.

A novel composite photocatalyst with hydrophobicity, modified Sr/TiO2-PCFM (porous ceramic filter media), was synthesized and characterized by applying X-ray fluorescence (XRF), scanning electron microscope and energy dispersive spectroscopy (SEM/EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), the Brunauer-Emmett-Teller (BET) method, Fourier transform infrared (FTIR) spectroscopy and UV–visible diffuse reflectance spectroscopy (UV–vis DRS). The results showed that the composite photocatalyst possessed a pure and highly crystalline anatase TiO2 layer and large specific surface area. The photodegradation of acephate by Sr/TiO2-PCFM was investigated under various conditions, e.g., the adsorption time, initial acephate concentration, Sr/TiO2-PCFM dosage, and pH. The acephate-preferred photocatalytic performance of the modified Sr/TiO2-PCFM with hydrophobic characteristics was explored for the first time in this study. The results revealed that the photocatalytic degradation process for the modified Sr/TiO2-PCFM preferred acephate over methylene blue (MB) in the acephate/MB mixture under ultraviolet light irradiation. The underlying mechanisms of the preferential degradation process of modified Sr/TiO2-PCFM was also studied. The results indicate that the modified Sr/TiO2-PCFM is a promising candidate for the preferential degradation of refractory organic matter in organophosphorus pesticides contaminated wastewater.

The increasing carbon dioxide (CO2) emissions from coal-fired power plants exacerbates the need for polymeric sorbents that can preferentially capture CO2 over nitrogen (N2). Herein we report two amine-functionalized microporous organic polymers (PTPNHs) through one-step facile modification of carboxyl-rich microporous organic polymers (PTPMA) that was prepared from a classic Friedel–Crafts coupling of commercially available monomers. The amidation chemistry enables an unprecedented morphology evolution of the microporous organic polymer from nanospheres to uniform nanorods and the choice of amidation agents allows a good control on the diameter and length of the as-made nanorods. More interestingly, the amine-appended PTPNHs show enhanced CO2 adsorption per unit surface area (0.281 mg/m2, at 273 K/1.0 bar) and exceptionally high ideal selectivity (CO2: N2 = 123) with high affinity towards CO2, despite of their decreased Brunauer–Emmett–Teller (BET) surface areas (554 m2 g−1). The CO2 adsorption per unit surface area of the nanorods is about 1.6 folds of that of pristine PTPMA. This study constitutes a step on regulating channel surface polarity and morphology control, and offers the prospect for low-cost direct CO2 capture technologies.

Advanced and effective adsorbents synthesized via cost-effective methods are needed for CO2 capture applications. Heteroatom doping is regarded as one of the major factor of the porous carbons for efficient CO2 adsorption. In the present study, oxygen and sulfur enriched carbon monoliths were prepared using nanocasting technique followed by chemical activation method. Low-cost phenol-formaldehyde (PF) resin and sodium thiosulphate were chosen as the carbon and sulfur source, respectively. The surface area of the monolithic carbons varied from 390 to 510 m2 g−1 and sulfur content was 2.89 wt% in the S-doped monolith. The effect of different adsorptive operating conditions i.e. adsorption temperatures and CO2 concentrations on the CO2 capture capacities were evaluated. The nanocasted monoliths exhibited excellent dynamic adsorption capacities (1.35–2.10 mmol g−1), which are much greater than in the case of direct carbonized PF sample (0.97 mmol g−1). This is ascribed to the fact that the surface area gets enhanced by implementing nanocasting method whereas the incorporation of oxygen and sulfur functionalities increases the basic character of the monoliths. The as-prepared monolith shows the stable and excellent regenerability over subsequent adsorption and desorption cycles. Moreover, the Temkin isotherm model best fitting with adsorption data indicates the heterogeneous surface of the monoliths. Combined with the effective synthesis of the monoliths, high CO2 uptake, and easy regenerability could make it a most suitable material for CO2 adsorption in the practical applications.

A novel thermometer, qualified with miniaturization, real-time monitoring, non-invasion, remote-control, and high spatio-temporal resolution, is urgently required for temperaturedetecting of sub-micrometric objects and in specific harsh conditions. Herein, we report an adaptable dual-mode optical thermometry platform LiTaO3:Ti4+, Eu3+@PDMS. A proof-of-concept implementation based on fluorescence thermometer (FT) demonstrates outstanding temperature sensing performance with excellent reversibility. The maximum Sa and Sr are as high as 0.671 and 5.425% K−1, respectively, with minimal temperature resolution of 0.14 K. Whilst, the maximum Sa and Sr based on lifetime thermometer (LT) are determined to be 0.122 and 3.637% K−1, respectively, with superior temperature resolution of 0.027–0.058 K. Finally, flexible phosphor films and 3D micro-rod arrays with handily encrypted information are fabricated for the unclonable multi-modal/multi-dimensional anti-counterfeiting application by exploiting light, temperature and time-domains as the “key” to decrypt the “locked” ciphertext, which indicates the promising prospect in temperature sensing and anti-counterfeiting. This work not only paves a way for developing novel spatial/temporal dual-mode real-time thermometer based on synergetic luminescence of lanthanide (Ln) and transition-metal (TM) ions with high temperature sensitivity and resolution, but also opens a new “window” for extending the thermometer as a flexible device in advanced multi-mode multi-dimensional high-level secure anti-counterfeiting.

This article puts forward a novel approach of combining the battery-type charge storage material, Mn(OH)2, indirectly with the two-dimensional material, MoS2, to develop the composite MnCO3@MoS2 (designated as MCMS). A single-step facile hydrothermal method is described here for the synthesis of MCMS on a low-cost graphite substrate. Furthermore, this as-synthesized binder-free electrode is utilized as the negative electrode of an all-solid state asymmetric alkaline supercapacitor, employing NiCo2O4 as the high specific energy positive electrode material. The overall asymmetric cell is shown to achieve a high specific energy of 48.97 W.h.kg −1 at 600 W.kg −1 and a high specific power of 12 kW.kg −1 at 11.33 W.h.kg −1, within a potential window of 1.2 V. Also, the composite electrode notably retains 86.5% of its gravimetric discharge capacity after 10,000 cycles with complete retention of its coulombic efficiency. The present work contributes to the development of a facile strategy for the preparation of non-carbonaceous hybrid materials suitable for high specific energy negative electrodes.

Levofloxacin—a fluoroquinolone antibiotic—is a potential wastewater contaminant generated by pharmaceutical industries. Novel one-dimensional disilver dimolybdate (Ag2Mo2O7) structures were developed to form a heterojunction with thin nanosheets of MoS2 on the surface of Ag2Mo2O7. A photocatalyst was used for the efficient removal of levofloxacin under visible light. The processing of the Ag2Mo2O7 structures was optimized by altering the hydrothermal duration with structural analysis using Rietveld refinement. An enhanced catalytic activity for levofloxacin degradation (efficiency of 97%) was observed with 30 wt% MoS2/Ag2Mo2O7, following first-order kinetics. The superior activity is ascribed to the well-aligned and favorable band positions, which allowed efficient charge transfer between the photogenerated charge carriers. The direct Z-scheme led to the photogeneration of a large number of electrons at the MoS2 surface. An investigation with radical scavengers indicated that superoxide radicals played a significant role in the degradation process, which was confirmed by electron spin resonance spectral measurements. Detailed parametric studies were performed, and the reaction mechanism was examined, providing an insight into the development of such hybrid microcomposites for the removal of hazardous pharmaceuticals from the environment.

As a class of emerging organic contaminants (EOCs), organophosphate flame retardants (OPFRs) have been raising concern due to their persistence, bioaccumulation and toxicity. Therefore, it is urgent need to develop environmental-friendly and high-efficient techniques to remove OPFRs. The degradation kinetics and mechanism of tris-(2-chloroisopropyl) phosphate (TCPP), a representative OPFRs, by UV/TiO2 photocatalytic degradation were explored in current research. It was found that degradation reaction was well documented by first-order kinetics with a kobs of 0.3146 min−1, and hydroxyl radical was identified as a dominating contributor for the TCPP elimination. Simultaneously, six steady intermediate products were generated with the release of Cl− and PO43− as photocatalytic reaction further proceeded. The degradation efficiency can be interfered by natural organic matters, anions and pH value, implying that an incomplete mineralization of TCPP could be ubiquitous in heterogeneous water matrix. Combining the proteomics analysis with KEGG metabolism networks analysis, the process of transmembrane transport and energy generation in Escherichia coli altered by intermediates has proved that the intermediates could be transported and utilized through cellular metabolism. Moreover, the diminution of stress resistance suggested that the toxicity of degradation products through UV/TiO2 photocatalytic degradation was lower than that of intact TCPP. To sum up, environmental safety of degrading intermediate products and the satisfactory detoxification effect of TCPP were identified under appropriate mineralization, indicating that UV/TiO2 photocatalysis technique was safe and high-efficient for TCPP control.

Bacterial infection is one of the serious problems during wound healing. Antibiotics and traditional antibacterial treatment can produce side effects, such as bacterial resistance, cell toxicity, during the long-term interaction with bacteria. Therefore, developing new antibacterial materials and methods for rapid and safe disinfection in wound healing is important. This work fabricated a hybrid hydrogel incorporated with Ag3PO4/MoS2 composites for rapid sterilization during wound healing. This hydrogel exhibited a superior antibacterial activity within 5 min by co-irradiation of 660 nm visible light (VL) and 808 nm near infrared (NIR) light due to the synergistic effects of both photodynamic antibacterial and photothermal antibacterial treatments. In addition, the antibacterial hydrogel could promote the wound healing compared with the pure hydrogel and medical gauze (MG) and cause no noticeable organ abnormalities in rats during the wound healing process.

Effects of metal ions on the adsorption of organic pollutants have drawn great interests considering their coexistence and interactions in aqueous solution. However, the potential influencing mechanisms of metal ions on the adsorption of organic pollutants at a molecular level were rarely studied. Here, we investigated the effects of Cu(II) on the adsorption of 17β-estradiol (E2) and sulfamethoxazole (SMX) by carboxylic and amino CNTs/CoFe2O4 composites, and the mechanisms were revealed by spectroscopy analyses and density functional theory (DFT) calculations. The results showed distinct effects of Cu(II) on SMX and E2 adsorption by CNTs/CoFe2O4. For E2, a nonionic chemical, Cu(II) slightly inhibited E2 adsorption by CNTs/CoFe2O4 due to the increased aggregation of the composites induced by Cu(II). For SMX, an ionic chemical, Cu(II) enhanced SMX adsorption significantly mainly due to Cu(II) bridging and stronger π-π interactions between SMX and Cu(II) complexes and CNTs. The complexation of SMX with Cu(II) was confirmed by the fluorescence, ultraviolet (UV), and attenuated total reflection fourier transform infrared spectroscopy (ATR-FTIR) analysis. DFT calculation further revealed that isoxazole ring nitrogen, sulfonamide nitrogen, amino nitrogen, and sulfonyl oxygen were the four possible binding sites in SMX with Cu(II). The adsorbed Cu(II) on CNTs/CoFe2O4 could form complexes with SMX, and the binding between SMX and Cu(II) enhanced the π-π interactions between SMX and CNTs. These two aspects led to the enhanced adsorption of SMX. This study provides new insights into the molecular interactions among Cu(II), SMX, and CNTs, and it sheds lights on the adsorption mechanisms of organic pollutants by CNTs in the presence of metal ions.

Biochar (BC) is usually applied in the remediation of contaminated water and soil as an excellent adsorbent, but recently, the BC-induced catalytic degradation of organic contaminants by persistent free radicals (PFRs) is attracting considerable attention. In this study, BC was prepared from the pyrolysis of sewage sludge and used to activate hydrogen peroxide (H2O2) for the degradation of ciprofloxacin (CIP) in water. Results showed that the HNO3 modified-BC exhibited better catalytic ability to activate H2O2 than the raw BC. Under similar conditions: pH 7 and H2O2 1.0 mmol/L, the removal efficiency of CIP by HNO3 modified-BC/H2O2 (93.00%) was obviously superior to that of BC/H2O2 (70.60%). The calculated contributions of adsorption and degradation to CIP removal demonstrated that BC exhibited certain CIP adsorption ability, but the contributions of adsorption led by raw BC and HNO3 modified-BC were only 38.31% and 29.81%, respectively. The proportion of catalytic oxidation induced by PFRs in BC accounted for 61.69% and 70.19%, suggesting the important role of PFRs in CIP removal. HNO3 modification not only altered the surface characteristics of BC, but also improved the quantities and types of PFRs in BC, which promoted the production of OH. In addition, the possible mechanism for H2O2 activation by PFRs in BC is that the single-electron transferring from sp2 C C, C O, pyridonic-N and pyridinic-N of PFRs in BC to H2O2, thus leading to the generation of OH.

Pristine graphitic carbon nitride (g-C3N4) suffers from poor photocatalytic activity due to its limited light adsorption, small specific surface area and feasible recombination of photogenerated charge carriers. One practical approach to solve the problem of low solar-to-hydrogen efficiency is nanostructuring the morphology of g-C3N4 to enhance its light-harvesting property and boost the rate of charge-carrier transportation. Here, we present a strategy to optimize the textural properties and catalytic performance of g-C3N4 via using oxamide (OA) as a chemical modifier in the precursor solution, which significantly make the light absorption edge shift from 440 to 650 nm. Moreover, the nanostructure of the resultant g-C3N4 can be easily tuned with increasing the amount of oxamide. The morphological features of g-C3N4 materials change from sheet-like structure to tubular structure, porous nanotube and eventually interconnected porous sheet. More interestingly, the unique g-C3N4 nanostructure offers advantages of a broader solar absorption spectrum and accelerates charge carrier dynamics that are favorable for advancing photocatalytic performance. The findings provide insightful information that can be used to understand the structure-property relationship in g-C3N4 nanostructures for improved solar-to-fuel conversion.

Although carbon materials have shown large potential as efficient electrocatalysts for oxygen reduction reaction (ORR), their practical performance with high energy density and power density is difficult to maintain under high mass-loading due to the compact restacking that seriously hinders mass/charge diffusion. To overcome this issue, we demonstrate the design and synthesis of hierarchical Co-N-codoped carbon nanotube hollow microspheres (CNT HMSs) with high disperse, large surface area and uniform mesopores, which effectively guarantees the high electrochemical activity and stability towards ORR even under high mass-loading. As a result, the power density of Zn-air battery based on CNT HMS gradually enhances from 52.8 to 183.8 mW cm−2 with a good linear relationship when the mass-loading increases from 1.5 (traditional used for most reported works) to 6.0 mg cm−2, indicating a well-preserved catalytic activity with high mass-loading. In addition, the long-term stability (10 h) test illustrates that monodisperse morphology and uniform size distribution of CNT HMS have been well maintained, while the referent carbon particles show serious agglomeration and obvious increased particle size. This suggests a much enhanced stability of CNT HMS compared with traditional particles, which offers large opportunity for the practical applications in metal-air batteries or fuel cells.

This study investigated the role of cathode conditions and microbial fuel cell (MFC) connection modes of a 30 L pilot-scale constructed wetlands-microbial fuel cell (CW-MFC) in the performance of wastewater treatment and power generation. A MFC with four anodes and one cathode was integrated into constructed wetland (CW) to form a CW-MFC. Ten cathode working conditions of different connections, aeration and local effluent recirculation were tested and interpreted. The results demonstrated that activated cathode to guarantee cathode reaction is vital for CW-MFC. Higher power output of MFC was achieved with larger activated cathode area and wetting cathode environment. Parallel connection (each anode connected to cathode with separated resistor) of MFC was much better than combined connection (all anodes connected to cathode through one resistor only). The best wastewater treatment efficiency (91.7% of COD, 97.3% of ammonia-N) of the CW-MFC was reached with the highest power output (7.99 mW/m2) of MFC.

Fe-Mn binary oxides (FMBOs) with different molar ratios of Fe and Mn (1:1–8:1) synthesized in a redox-precipitation method were investigated for the activation of a combination of persulfate (PS) and hydrogen peroxide (HP) for the degradation of 2,4-dinitrotoluene (2,4-DNT). X-ray diffraction and field-emission scanning electron microscopy were used to demonstrate FMBOs with different molar ratios exhibited no significant influence on crystallinity and morphology. The degradation efficiency and kinetics of 2,4-DNT in the FMBOs/PS/HP system were investigated. The results showed that F4.5M1BO exhibited better effectively heterogeneous catalytic activity in the activation of the combined PS and HP. The effects of initial HP and PS concentrations, F4.5M1BO dose, initial pH, and coexisting anions on the degradation efficiency and kinetics of 2,4-DNT were comprehensively investigated. A possible activation mechanism in the F4.5M1BO/PS/HP system was proposed based on electron paramagnetic resonance, radical scavenger tests, X-ray photoelectron spectroscopy, and Fourier transformation infrared spectroscopy. The results showed that Fe(II), Mn(II), and Mn(III) ( is representative of the element in solid form) are active sites on the surface of F4.5M1BO that effectively activated the combined PS and HP to generate the dominant SO4 − and HO . Furthermore, the proportions of lattice oxygen, surface adsorbed species, and adsorbed molecular water activated of the combined PS and HP. The strong synergistic interaction reaction among Fe(III), Mn(III), Mn(IV), and HP could be deduced and confirmed. These findings provide new insight into the potential of F4.5M1BO as a heterogeneous catalyst in the activation of the combined PS and HP for improving the degradation of refractory organic pollutants.

Granular activated carbon (GAC) was modified by the addition of conductive nano-Fe3O4 for use in the anaerobic digestion of low-strength wastewater. This new material, called magnetic granular activated carbon (MGAC), was fabricated by the facile co-precipitation method. The MGAC exhibited superior electro-conductivity, electron transfer rate, and methane production. The observed conductivity of the MGAC (17.5 ± 0.6 mS cm−1) was 2.03 times that of the GAC (8.6 ± 0.3 mS cm−1). With the MGAC, the effluent total chemical oxygen demand concentration (44.5 ± 1.5 mg L−1) was 33% lower than that obtained with the GAC and 43% lower than that obtained in the control experiment (with no conductive additive). The methane production obtained with the MGAC (4.7 ± 0.2 mL per cycle) was 3.6 times that of the control and 1.57 times that of the GAC. The anaerobic system with the MGAC exhibited stronger electrochemical response to riboflavin and cytochrome C. The peak current at 0 V (reduction peak, cytochrome C) of the MGAC was 45.1 μA, which was 54.0% higher than that of the GAC and 54.8% higher than that of the control. The electron accepting capability [56.71 ± 0.70 μmol e− (g char)−1] was 2.75 times that of the GAC. The MGAC also exhibited a higher abundance of functional microorganisms. These results demonstrated that the MGAC enhanced the electron transfer between bacteria and archaea, improved methane production, and produced high-quality effluent.

A series of novel ternary Ag2WO4/BiOI/CoFe2O4 hybrids synthesized by a facile modified deposition-precipitation method were utilized to explore their activities for toxic elemental mercury (Hg0) removal under fluorescent light (FSL) irradiation. The as-prepared materials were characterized by various methods and the experimental parameters such as Ag2WO4 content, fluorescent light irradiation, and inorganic anions were investigated in detail. The characterizations revealed that Ag2WO4 and CoFe2O4 were successfully dispersed on the surface of BiOI and heterogeneous hybrid was generated. The separation of electrons and holes (h+) could be efficiently promoted due to the combination of Ag2WO4, BiOI and CoFe2O4 with suitable match of band gaps under FSL irradiation. The experimental results manifested that Ag2WO4 content, fluorescent light irradiation, inorganic carbonate ions and SO2 gas all possessed conspicuous effects on Hg0 removal. Among the heterogeneous photocatalysts, Ag2WO4(0.1)BiOI/CoFe2O4 demonstrated the optimal activity for Hg0 removal and superior stable performance, which also could be easily recovered from the reaction solution by an extra magnet. Superoxide radicals ( O2−) and holes (h+) were confirmed to be the main reactive substances for higher Hg0 removal.

The use of engineered nanomaterials in membrane design has proved promising to enhance the membrane separation performance and confer additional specific functionalities to a membrane. Enlightened by the robust adhesion of bioinspired coatings, super-hydrophilic titanium dioxide (TiO2) coupled with polyethylenimine (PEI) was stably anchored on the surface of a polydopamine (PDA)-coated membrane through vacuum filtration. The combination of organic-inorganic hybrid layer with PDA coating endowed the composite membrane with an excellent separation performance. Further in-situ formation of silver nanoparticles (Ag NPs) onto the composite membrane enabled the membrane with a high antibacterial activity. The effect of TiO2 concentration on membrane separation performance was studied. The results demonstrated that PEI plays a key role to achieve a superior dye rejection, although it resulted in a distinctly decrease of water permeability. As the TiO2 loading amount increases, the water permeability notably enhanced with an overall high rejection of dye solutions. The optimal composite membrane had a quite high water permeability of 40.6 L m−2 h−1 bar−1, and an excellent dye rejection. Plate counting method results showed that the Ag decorated composite membrane had a high bacteriostatic rate of 99.7%. This facile fabrication procedure and outstanding separation performance suggest that the modified membranes have a high potential in treating dye wastewater.

Currently, there are three primary obstacles to the development of high-performance supercapacitors: low electron conductivity of the electrode materials used, their poor ion-transport efficiency, and the unstable structure. Herein, to overcome these obstacles, one-dimensional Zn2GeO4 (ZGO) rods were grown within a carbon nanotube (CNT) framework using a simple one-step hydrothermal strategy for use as a supercapacitor electrode material. The crosslinked ZGO/CNT-O hybrid exhibits a large contact surface area with respect to electrolytes, contains abundant electrochemical active sites, and has short ion-diffusion paths. Further, the flexible CNTs act as superior connective bridges, promoting electron transmission and resulting in a stable structure. The ZGO/CNT-O hybrid showed a specific capacitance of 164.25 F/g at a current density of 1 A/g. It also displayed superior cycling durability, exhibiting a specific capacity of 120 F/g at a current density of 10 A/g, even after 200,000 cycles. A simple crosslinking strategy and prolonged cycle durability are demonstrated, which endow ZGO/CNT-O with potential for use in supercapacitor electrodes.

The transformation of amorphous phase metal-organic gels (MOGs) into crystal metal-organic frameworks (MOFs) is an expectant and effective strategy for crystal growth. Herein, a novel solvent-triggered method on transforming amorphous copper-based metal-organic gels (Cu-MOGs) into highly monodisperse MOFs crystals with controlled shapes, namely, dodecahedron, hollow dodecahedron, polyhedron, cube, cruciate flower and cross star, was developed in a mild condition. The stoichiometric ratio of metal ions to ligands in Cu-MOGs and the constituent of solvent were both demonstrated to play unique and key roles in determining the final shape of the MOFs crystals. Meanwhile, the crystal morphological evolution process from original fibrillar network to the multi-shape MOFs disclosed that this novel solvent-triggered transition from amorphous phase MOGs to MOFs crystalline phase were carried out in two ways (i) dissolution-recrystallization and (ii) self-assembly of the pristine fibrillar network. This novel approach successfully connects the emerging MOFs with the supramolecular gels-based soft materials, opening up exciting ways for simple and efficient synthesis of MOFs materials.

In this work, partially dehydrated zinc hydroxide sulfate nanoplates are synthesized by facile chemical bath deposition together with subsequent heat dehydration. The nanoplates exhibit well-defined hexagonal plate structure with smooth surface and no visible defects can be observed. Then, the corrosion protection performance of the nanoplates-embedded fluorocarbon coatings was investigated in 3.5 wt% NaCl aqueous solution. It turns out that the well dispersed nanoplates greatly enhance the protection ability of composite coatings. Once electrolyte permeates into the coating matrix and reaches the surfaces of nanoplates, the nanoplates can actively trap water molecules and ions (Cl− and Na+) therein through phase transition behavior, thus inhibiting the diffusion of electrolyte to the interface between coating and substrate. Meanwhile, the concomitant swelling of nanoplates blocks the diffusion of corrosive media, thus further enhancing the protection performance. The multi-functions of this material impart superior passive barrier and active barrier abilities to polymer coating.

A methodology based on the borescopic technique has been developed and validated for tracking solid movement within a conical spouted bed. The procedure developed and fine-tuned allows monitoring the descending and ascending optical flow of both spherical and irregular particles in the annulus (dense zone) and spout (dilute zone) in the bed. A high speed camera (up to 16,000 fps) fitted with a fiber optic continuous light source was used for recording, and an image treatment algorithm modified and adapted to account for differences in particle shape and bed density (dilute or dense) was applied to the registered data. The procedure allows gathering information on the velocity of particles in a wide range of sizes, from a few millimeters ( d p ¯ = 7 mm) to micrometers ( d p ¯ = 93 μm).

To upgrade the membrane separation process, there is a tremendous need to understand the process from the point of view of the membrane materials, e.g., their chemistry and material features. Functionalized by various alkyl- and fluoroalkylsilanes, zirconia membranes (pore size 3 and 200 nm) were systematically investigated from the material, physiochemical, and tribological points of view. The work shows the successful utilization of the modified ceramic membranes to niche application of water purification. Stable organic-inorganic membranes were applied in vacuum membrane distillation (VMD) for removal of hazardous volatile organic compounds (VOCs) butanol, methyl-tert-butyl ether, and ethyl acetate. Wettability, surface roughness, and adhesion were investigated, taking into account the type of modifiers (fluorine-free) and molecules with a different degree of fluorination. The impact of the type of reactive group in non-fluorinated modifiers on the material features and the separation effectiveness were discussed. Furthermore, mechanical and chemical stabilities were studied. The most significant was that utilization of non-fluorinated modifier makes it possible to generate stable hydrophobic membranes, with high reactivity during grafting, suitable for VMD. These membranes possess better transport properties and high mechanical stability in comparison with fluorinated ones.