Here, the Bi24O31Br10-based composite photocatalysts modified by bimetallic Bi and Mo nanoparticles (NPs) are designed and prepared (Bi-Mo-Bi24O31Br10). 2D ultra-thin Bi24O31Br10 nanosheets with suitable band gap and good chemical and optical stability are selected as the main catalyst to drive N2 fixation by generating hot carriers. The Bi NPs in the Bi24O31Br10 nanosheets serves as a buffer tank for electrons to improve the efficiency of electron transfer. Meanwhile, the Mo NPs serve as catalytic centers for N2 adsorption and activation, working synergistically to enhance the overall reaction efficiency. Resulting from semiconductor-to-metal-to-metal electron transfer path and the Mo metal adsorption and activation mechanism, the nitrogen fixation rate of the Bi-Mo-Bi24O31Br10 photocatalyst is as high as 191.2 mu mol g-1h-1, and it is 7.2 times compared to pure Bi24O31Br10. This work creates a novel framework for the rational design of highly efficient visible-light-responsive nitrogen fixation catalysts.

Photocatalytic water splitting has emerged as a viable strategy to address the prevailing environmental and energy dilemmas globally. Nonetheless, a significant obstacle to this sustainable technology lies in the inadequate separation and effective utilization of photogenerated electron-hole pairs within photocatalytic materials. Here, we constructed a novel double S-scheme MIL-125(Ti)/ZnIn2S4/ZnS quantum dots (MOF/ZIS/ZnS) heterojunction photocatalyst by facile hydrothermal and solvothermal method for photocatalytic hydrogen evolution (PHE). The optimal MOF/ZIS/ZnS photocatalyst demonstrates a remarkable hydrogen generation rate of 0.943 mmol center dot h-1 center dot g-1, and it is 10.84 times higher than pure ZIS (0.087 mmol center dot h-1 center dot g-1). This significant boost in hydrogen production efficiency is due to the creation of a dual S-scheme heterojunction and an intrinsic electric field (IEF) among MOF, ZIS, and ZnS, which promotes charge transfer, reduces photogenerated carrier recombination, prolongs the lifespan of light-induced carriers and boosts the redox potential of photoexcited charges. This study provides fresh perspectives on the optimal design of dual S-scheme photocatalysts by harnessing energy band manipulation and IEF adjustments.

In this study, a novel poly(AMIM-co-AC) (PAMIMAC) copolymer was successfully synthesized through copolymerization of 1-allyl-3-methylimidazolium chloride (AMIM) and acrolein (AC); a series of anion exchange membranes (AEMs) with network structures were fabricated through an efficient solvent casting method by blending varying proportions of PAMIMAC with polyvinyl alcohol (PVA) and ethylene-vinyl alcohol copolymer (EVOH) in dimethyl sulfoxide (DMSO). The resulting membranes underwent comprehensive characterization employing 1H NMR, FTIR, XPS, SEM, and AFM techniques to elucidate their chemical composition and morphological features. Systematic evaluation revealed excellent dimensional stability, acid resistance, mechanical stability, and thermal stability, along with favorable water absorption rates and competitive ion exchange capacities. Notably, in diffusion dialysis (DD) performance tests, the optimized membranes demonstrated superior proton permeability coefficients (UH +) (UH + = 14.2-42.3 x 10-3 m/h) and separation factors (S = 63-27) compared to the commercial DF-120 membrane (UH + = 9 x 10-3 m/h, S = 18). This remarkable enhancement in both permeability-selectivity and operational stability positions these PAMIMAC-based AEMs as promising candidates for practical separation applications. The combination of straightforward fabrication methodology, stable physicochemical properties, and exceptional DD performance suggests significant potential for industrial implementation in acid recovery processes and related membrane-based separation technologies.

The CO2 photoreduction to high-value-added products is accompanied by a complex activation and dissociation process, and the construction of multiple active sites on photocatalysts for both CO2 reduction and H2O dissociation simultaneously is still a daunting challenge. Herein, Cu as Lewis acid (LA) sites and P as Lewis base (LB) sites were successfully modified on the surface of tubular g-C3N4 (P/Cu-TCN) to improve the performance of CO2 photoreduction to CH4 with H2O as a proton donor. The production of CH4 is as high as 63.95 mu mol g- 1 h- 1 over optimal P/Cu-TCN photocatalyst with an outstanding selectivity. The performance is much higher than those of the reported g-C3N4-based photocatalytic systems. Experimental results combined with theoretical simulation results show that the electrophilic Cu (Lewis acid) centers induce the activation of the C--O bond in CO2, while electron-enriched P (Lewis base) sites enhance the adsorption of pure water molecules and subsequent proton transfer processes. The incorporation of Cu and P acid-base pairs not only mitigates the elevated Gibbs free energy barrier associated with C--O bond cleavage during CO2 photoreduction and facilitates the overall protoncoupled electron transfer kinetics, but also suppresses the recombination of photogenerated charge carriers while enhancing charge transport efficiency. All of these together improve the catalytic efficiency of the CO2-to-CH4 transformation. This study offers research suggestions for the modification of g-C3N4 to enhance CO2 reduction.

The lack of active sites and the low availability of photoelectrons severely limit the photocatalytic reduction of nitrogen to ammonia in semiconductor materials. Here, we successfully designed a BiOBr/O-v-TiO2-Cu heterojunction catalyst toward N-2 fixation into NH3. The optimized BiOBr/O-v-TiO2-Cu heterojunction has a promising photocatalytic performance and stability with the highest NH3 yield of 259.82 mu mol center dot g(-1)center dot h(-1). The combination of detailed theoretical simulation calculations and comprehensive characterizations indicates the BiOBr/O-v-TiO2-Cu heterojunction with oxygen vacancy (O-v) stabilized Cu nanoparticles (NPs) as active sites can effectively adsorb and activate N-2 molecules. The close contact between BiOBr and O-v-TiO2 elevates the quick transmission of photogenerated electrons at the interface and the enrichment on Cu NPs. This work not only provides an efficient photocatalyst for the N-2 reduction, but also supplies theoretical support for identifying the active sites and charge transfer kinetics of the nitrogen reduction reaction.

Given the substantial environmental pollution from industrial expansion, environmental protection has become particularly important. Nowadays, anion exchange membranes (AEMs) are widely used in wastewater treatment. With the use of polyvinyl alcohol (PVA), ethylene-vinyl alcohol (EVOH) copolymer, and methyl iminodiacetic acid (MIDA), a series of cross-linked AEMs were successfully prepared using the solvent casting technique, and the network structure was formed in the membranes due to the cross-linking reaction between PVA/EVOH and MIDA. Fourier transform infrared spectrometer, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy were used to analyze the prepared membranes. At the same time, its comprehensive properties which include water uptake, linear expansion rate, ion exchange capacity, thermal stability, chemical stability, and mechanical stability were thoroughly researched. In addition, diffusion dialysis performance in practical applications was also studied in detail. The acid dialysis coefficient (U-H(+)) ranged from 10.2 to 35.6 x 10(-3) m/h. Separation factor (S) value ranged from 25 to 38, which were all larger than that of the commercial membrane DF-120 (U-H(+): 8.5 x 10(-3) m/h, S: 18.5). The prepared membranes had potential application value in acid recovery. HIGHLIGHTS center dot The preparation method of the membranes is simple. center dot The membrane is based on PVA/EVOH/MIDA. center dot The raw materials are cheap and easy to obtain. center dot The acid recovery performance is excellent by diffusion dialysis. center dot The prepared membranes had potential application value in acid recovery.

Quaternized polyepichlorohydrin (PyPECH) was successfully synthesized by the quaternization reaction between Pyridine and PECH. The correctness of the experimental result was demonstrated through Fourier transform infrared spectroscopy (FTIR) and 1H NMR spectroscopy. With the combination of PyPECH, Polyvinyl alcohol (PVA), Ethylene-vinyl alcohol copolymer (EVOH), and Tetraethyl orthosilicate (TEOS), five different anion exchange membranes (AEMs) for diffusion dialysis (DD) were successfully prepared. The structure of prepared membranes was characterized and analyzed in detail, which included FTIR, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscope (TEM). At the same time, the comprehensive performances which included wate uptake (WR), linear expansion rate (LER), ion exchange capacities (IEC), thermal stability, chemical stability, and mechanical stability were also discussed at great length. In DD experiments, the prepared membranes demonstrated excellent acid recovery ability, with the acid dialysis coefficients (UH+) of 11×10−3 to 35.5×10−3 m/h. Furthermore, according to the test results, the prepared membranes exhibited a higher S value (35−50) than that of commercial membranes DF-120 (18.5). Therefore, the prepared membranes had competitive advantage in acid recovery via diffusion dialysis.

Anion exchange membranes were prepared by a simple method on the basis of polyvinyl alcohol (PVA) and 1,4-Piperazinedicarboxaldehyde (PDC). A network structure was formed in the membranes by cross-linking between PVA and PDC. The mechanical stability and acid stability the prepared membranes was tested. The TS value was tested as 17.5–37.8 MPa, Eb was 120.4–54.7% and the mass retention in the acid environment was 98.4–97.2%. Meanwhile, the physicochemical properties of membranes, such as thermogravimetric analysis (TGA), water absorption (WR), ion exchange capacity (IEC) and linear expansion rate (LER). WR was 106.9–136.7%, IEC was 1.03–1.55 mmol/g, and LER was 37.93–33.33%. In practical application, diffusion dialysis (DD) performance of membranes were tested. In DD test, the acid dialysis coefficient (UH+) was 17.5–27.9 × 10−3 m/h, and the separation factor (S) was 31.25–23.38. The UH+ and S were all higher than commercial membrane DF-120 (UH+ is 9 × 10−3 m/h and S is 18.00). Results were shown that the comprehensive properties of membranes were good. Therefore, the prepared membranes had broad application prospects for acid recovery by diffusion dialysis.

In this work, a novel silane coupled cationic precursor (SAGS) was synthesized by 3-glycidyloxypropyltrimethoxysilane and sodium 2-((2-aminorthyl)amino) ethanesulfonate. A series of cation exchange membranes were prepared with poly(vinyl alcohol) (PVA) and SAGS by a sol-gel-based process. The structure of the prepared membranes were characterized by Fourier transform infrared spectrum (FTIR) and scanning electron microscopy (SEM), and its properties were studied by water uptake (WR), cation exchange capacity (CEC), linear expansion ratio (LER), alkali stability, thermogravimetric analysis (TGA), mechanical properties, and diffusion dialysis performance. FTIR and X-ray photoelectron spectroscopy (XPS) confirmed the successful preparation of SAGS membranes, and SEM images showed that the prepared membranes were dense and uniform. The WR values of the SAGS membranes were in the range of 91.49–122.39%, and the LER values were 17.65–28.21%. In addition, the SAGS membranes had suitable CEC value, good alkali resistance, and thermal stability which ensured the application of membranes in the field of diffusion dialysis (DD) for alkali recovery. In the DD test, the dialysis coefficients of NaOH (UOH) ranged from 0.012 mm/h to 0.023 mm/h, and the separation factors (S) was in the range of 30.77–16.43. In conclusion, the prepared CEM containing silicon oxygen bonds by PVA and SAGS reaction has the advantages of low price, friendly environment, good alkali resistance, simple preparation process, and great application potential in the textile manufacturing wastewater recovery.

Rapid and efficient transfer and separation of photo-induced carriers are critical for designing en-vironmentally friendly and efficient photocatalysts in catalytic hydrogen evolution. Here, we design a 0D/2D S-scheme heterojunction involving ZnIn2S4 (ZIS) nanosheets self-assembled with SnS2 quantum dots (QDs). The formation of the S-scheme ZIS/SnS2 QDs heterojunction is demonstrated by experimental character-istics and density functional theory (DFT) analyzes, which greatly promotes charge transfer and transport under the interfacial electric field (IEF), lengthens carrier lifetime, enhances light-harvesting properties, and significantly decreases the Gibbs free energy during the catalysis reaction. Therefore, the optimized ZIS/SnS2 photocatalyst achieves a high hydrogen production rate of 1.13 mmol g-1h-1, which is 16.14 folds the one of pure ZIS. This study provides novel perspectives into the reasonable design of S-scheme photocatalyst by virtue of the theories of energy band engineering and IEF adjustment. & COPY; 2023 Elsevier B.V. All rights reserved.

In this paper, polyepichlorohydrin (PECH) quaternized with N-methylimidazole (ImPECH) was successfully synthesized. ImPECH, polyvinyl alcohol, and tetraethyl orthosilicate were used to prepare anion exchange membranes that possessed a semi-interpenetrating polymer-network structure. These membranes were designed for acid recovery by diffusion dialysis (DD). The successful synthesis of ImPECH was verified via Fourier transform infrared spectroscopy (FTIR) and 1H NMR spectroscopy. Meanwhile, the prepared anion exchange membranes were characterized by FTIR, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). In addition, the ion exchange capacity (IEC), water uptake (WR), tensile strength (TS), linear expansion rate (LER), and elongation at break (Eb) of each membrane were characterized. In DD application tests, acid dialysis coefficients (UH+) of the membranes ranged from 8.56 x 10-3 m/h to 27.33 x 10-3 m/h and separation factor (S) values were all above 22.55. These results showed that anion exchange membranes had higher UH+ and S values than commercial membrane DF-120 (UH+ is 9.00 x 10-3 m/h and S is 18.00) and other better general properties including the LER, TGA, TS, and so on. The prepared membranes showed a wide application prospective for acid recovery via DD.

Herein, we discussed the synthesis of quaternized poly epichlorohydrin (QPECH) by the reaction of poly epichlorohydrin (PECH) with N, N-dimethylethanolamine (DMEA). After that, different amounts of QPECH were mixed with the polyvinyl alcohol (PVA) and tetraethyl silicate (TEOS) to fabricate a series of anion exchange membranes (AEMs) by sol-gel reaction. The chemical structure of the synthesized QPECH was effectively proved by Fourier transform infrared (FTIR) and 1H NMR. Hereafter, the composite membrane structure was determined by FT-IR, X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM), and the physical and chemical properties such as thermogravimetric analysis (TGA), water uptake (WR), ion exchange capacity (IEC), linear expansion rate (LER) and diffusion dialysis (DD) were tested. The performance, such as acid recovery and selectivity of PVA/QPECH composite membranes with different QPECH content, was discussed comprehensively. The results showed that the WR of the composite membrane was 82.35-158.54%, the LER was 19.23-40.74%, and the IEC was from 0.64 to 1.76 mmol/g. In the DD test simulating waste acid recovery, the acid dialysis coefficient (UH+) was in the range of 11.1-30.0*10-3 m/h, and the separation factor (S) was 24.79-42.24. The UH+ and S of the composite membranes were all better than that of commercial membrane DF-120. In conclusion, this study demonstrated that the application of anion exchange membrane based on PVA/QPECH had the potential in acid recovery by DD method.

In order to improve the performance of the anion exchange membrane (AEM) used in acid recovery from industrial wastewater, this study adopted a new strategy in which brominated poly (2,6-dimethyl-1,4-phenyleneoxide) (BPPO) and polyepichlorohydrin (PECH) were used as the polymer backbone of the prepared membrane. The new anion exchange membrane with a net structure was formed by quaternizing BPPO/PECH with N,N,N,N-tetramethyl-1,6-hexanediamine (TMHD). The application performance and physicochemical property of the membrane were adjusted by changing the content of PECH. The experimental study found that the prepared anion exchange membrane had good mechanical performance, thermostability, acid resistance and an appropriate water absorption and expansion ratio. The acid dialysis coefficient (UH+) of anion exchange membranes with different contents of PECH and BPPO was 0.0173–0.0262 m/h at 25 °C. The separation factors (S) of the anion exchange membranes were 24.6 to 27.0 at 25 °C. Compared with the commercial BPPO membrane (DF-120B), the prepared membrane had higher values of UH+ and S in this paper. In conclusion, this work indicated that the prepared BPPO/PECH anion exchange membrane had the potential for acid recovery using the DD method.

采用端羟基硅油(PDMS-OH)引入聚氨酯预聚体链段,利用二羟甲基丙酸(DMPA)为亲水扩链剂制备了阴离子型含硅水性聚氨酯预聚体,再将其与三缩丙二醇二丙烯酸酯(TPGDA)聚合用以包覆石蜡芯材,获得阴离子型含硅水性聚氨酯壁材相变储能微胶囊,分析了PDMS-OH与聚醚多元醇(PPG2000)对相变储能微胶囊各项性能的影响.结果表明,PDMS-OH已成功接入聚氨酯预聚体主链,且壁材已成功包覆石蜡芯材,PDMS-OH的引入有助于提高壁材的力学强度,提高了相变储能微胶囊的芯材包覆率,其中PDMS-OH/PPG2000摩尔比为90:10时,熔融焓为157.25 J/g,结晶焓为183.17 J/g,石蜡含量达75.43％;并且有助于减小乳液中乳胶束的粒径,其中最小粒径为181.45 nm,从而大幅改善微胶囊芯材外泄的问题;另外,随着PDMS-OH/PPG2000摩尔比的提高,一段分解失重率下降幅度增大,表明芯材包覆率进一步提高,其中PDMS-OH/PPG2000摩尔比为90:10时,一段失重率达73.40％.

Formaldehyde, a common indoor air pollutant, may have adverse effects on human health. The detection of formaldehyde is vital for assessing personal exposure risks. In this study, a method for indoor gaseous formaldehyde detection was developed based on the derivatization of formaldehyde by magnetic multi-walled carbon nanotube (MWCNT)-supported 2,4-dinitrophenyl hydrazine (DNPH) and analysis by high-performance liquid chromatography with ultraviolet detection. The method exhibited high derivatization efficiency due to the immobilized DNPH and rapid separation of derivatives and impurities due to the magnetic solid material. The optimal analysis conditions were 30 min for the derivatization reaction time and 35 degrees C for the derivatization reaction temperature in an acidic reaction medium. Under these conditions, the linear range for the proposed formaldehyde detection method was from 0.01 to 5.00 mg/L, and the detection limit was 0.005 mg/L. This formaldehyde detection method is advantageous due to its simplicity, sensitivity, linearity, and stability.

Anion exchange membranes with auxiliary group were prepared by quaternized brominated polyphenylene oxide and hydroxyl tertiary amine. The basic properties of the membrane were characterized using ion exchange capacity, water content, linear expansion rate, thermal weight loss, acid resistance and microstructure of membrane, and so forth. The application of the membrane in the recovery of acid by diffusion dialysis (DD) was also explored showing the excellent comprehensive performance where the dialysis coefficient of HCl (UH+) increases from 0.011 to 0.033 m/h, but the separation factor (S) is over 35.6. Comparing with the commercial DF-120 membrane (0.009 m/h, 18.5), the auxiliary hydroxyl with group can improve DD performance of the membrane markedly. Our finding shows the membranes with auxiliary hydroxyl group developed here have great potential for high-efficiency acid recovery by diffusion dialysis.

介绍了聚苯醚(PPE)在化学改性方面的研究进展,简述了各种封端剂对低分子量PPE进行封端改性,重点描述了使用溴化、磺化等对PPE功能化改性,指出了目前将PPE由热塑性树脂向热固性树脂改性的发展方向,并对改性的PPE在阴离子交换膜中的应用进行了总结,得出了控制好吸水率、离子交换能力与力学性能的平衡是制备阴离子膜的关键.分析表明,提高耐碱性是今后制备阳离子交换膜的工作重点,对PPE在两种离子交换膜的应用进行展望.

The main obstacles to the photocatalytic reduction of nitrogen are the low separation efficiency of photogenerated charges and the few activation sites for nitrogen. It is highly desirable to explore new strategies for improving the nitrogen fixation performance of catalysts. Herein, the Bi metal active sites are constructed on the surface of BiOBr/BiOI heterojunction by in situ reaction, which promote the absorption, activation, and dissociation of nitrogen molecules. Moreover, the existence of Bi metal and BiOBr/BiOI heterojunction enhances the light absorption ability and facilitates the separation and transfer of photogenerated charges. The theoretical calculation also demonstrates that the BiOBr/BiOI/Bi composite has excellent electron structure and electron transfer efficiency. So, the ternary BiOBr/BiOI/Bi catalyst shows excellent performance of photocatalytic reduction of nitrogen to ammonia. The nitrogen reduction rate is 221.9 μmol g −1 h −1 , which is 7.6 and 5 times higher than that of pure BiOBr and BiOBr/BiOI. The mechanism of photocatalytic nitrogen fixation of the BiOBr/BiOI/Bi is proposed based on the experimental and theoretical results. This study provides a novel method for improving the photocatalytic nitrogen reduction performance of catalysts.

The development of photocatalysts with efficient charge separation and transferring is essential for efficient photocatalytic H2 generation. Here, we have constructed Sn2+ and Sn4+ double-doped ZnIn2S4 (Sn2+/Sn4+-ZnIn2S4) catalyst by using a one-step solvothermal method. Sn4+ replaces the Zn ion and creates an additional energy state near the Fermi level, which act as electron accepters. The receptor states boost the metallic conductive properties of ZnIn2S4 and reduce the recombination of photo-induced electrons and holes. The Sn2+ combines with edge S atoms of ZnIn2S4 due to the large ionic radius, which modulates the band gap structure. Both experimental results and theoretical calculations show that the Sn2+and Sn4+ ion double doping increases charge density and narrows the bandgap for light capture. Therefore, the Sn2+/Sn4+-ZnIn2S4 catalyst shows an excellent catalytic activity for hydrogen production (2.48 mmol·g−1·h−1), and it is 35.4 times that of the original ZnIn2S4 (0.07 mmol⋅g−1⋅h−1). This work opens a promising path for developing highly efficient photocatalysts for solar photocatalytic H2 generation.

Purpose The purpose of this paper is to study the influence of different factors on mud performance, find the best conditions and synthesize a new type of anti-collapse drilling polymer mud with higher stability. The anti-collapse mechanism of drilling polymer mud was also suggested. Design/methodology/approach Exploring the influence of different molecular weight thickeners, filtrate reducers, soda ash addition and film-forming components on the mud performance, so as to obtain the best ratio of anti-collapse drilling polymer mud. Findings The results show that the use of vegetable glue, sulfonate copolymer and vegetable fiber powder can synthesize a high-viscosity, high-stability, collapse-resistant mud. When the mass ratio of vegetable fiber powder: vegetable glue: sulfonate copolymer is 40:1:2, the mud viscosity is 21.2 s, the fluid loss in 30 min is only 12.5 mL, and the mud film thickness is 1.5 mm, which is one ideal anti-collapse polymer mud. Originality/value Compared with ordinary polymer mud and bentonite mud, this anti-collapse polymer mud not only uses vegetable glue instead of traditional tackifiers but also effectively uses vegetable fiber powder produced from waste wood, which is environmentally friendly and highly stable specialty. It can effectively improve the safety and quality of construction during drilling in water-sensitive geology.