Solar-driven Fenton-like reactions are promising strategies for degrading pharmaceutical wastewater to address environmental challenges and antibiotic pollution.However,its efficacy is limited by suboptimal light abso...Solar-driven Fenton-like reactions are promising strategies for degrading pharmaceutical wastewater to address environmental challenges and antibiotic pollution.However,its efficacy is limited by suboptimal light absorption efficiency,rapid charge recombination,and inadequate interfacial charge transfer.In this study,an inorganic/organic S-scheme photo-Fenton system of pseudobrookite/carbon nitride(FTOCN)was synthesized via a hydrothermally coupled calcination process for the effective purification of tetracycline antibiotics under visible-light irradiation.The optimized FTOCN-2 heterostructure exhibits a significantly enhanced TC degradation capacity of 90%within 60 min.The rate constant of FTOCN-2 is 1.6 and 5.2 times greater than those of FTO and CN,respectively.Furthermore,FTOCN exhibits high antibacterial efficacy,highlighting its potential application in the purification of natural water.Measurements via a range of analytical techniques,including Kelvin probe force microscopy,density functional theory calculations,in situ X-ray photoelectron spectroscopy,and femtosecond transient absorption spectroscopy,corroborate the S-scheme mechanism.This study provides a novel perspective for the development of photo-Fenton systems with S-scheme heterojunctions for water purification.展开更多
Fenton method combined with light to accelerate the production of free radicals from H2O2 can achieve more efficient pollutant degradation.In this paper,a novel BiOI/FeWO4 S-scheme heterojunction photocatalyst was obt...Fenton method combined with light to accelerate the production of free radicals from H2O2 can achieve more efficient pollutant degradation.In this paper,a novel BiOI/FeWO4 S-scheme heterojunction photocatalyst was obtained by in situ synthesis,which can activate H2O2 and degrade the organic pollutant OFC(ofloxacin)under visible light.The S-scheme charge transfer mechanism was confirmed by XPS spectroscopy,in situ KPFM and theoretical calculation.The photogenerated electrons were transferred from FeWO4 to BiOI driven by the built-in electric field and band bending,which inhibited carrier recombination and facilitated the activation of H2O2.The BiFe-5/Vis/H2O2 system degraded OFC up to 96.4%in 60 min.This study provides new systematic insights into the activation of H2O2 by S-scheme heterojunctions,which is of great significance for the treatment of antibiotic wastewater.展开更多
Monotonic pore size and particles inseparability of metal-organic frameworks(MOFs)caused serious effects on its light absorption ability and charge separation,restricting its application for antibiotic such as levoflo...Monotonic pore size and particles inseparability of metal-organic frameworks(MOFs)caused serious effects on its light absorption ability and charge separation,restricting its application for antibiotic such as levofloxacin(LEV)degradation in water.In this study,a magnetically detachable nano-photocatalyst(ZnFe_(2)O_(4)@MIL-88A(Fe))was synthesized using a simple two-step hydrothermal technique.The morphology and microstructure analyses showed that n-type ZnFe_(2)O_(4)catalyst particleswere efficiently assembled onto the surface of MIL-88A(Fe)crystal.Photocatalytic activity studies indicated that the ZnFe_(2)O_(4)@MIL-88A(Fe)plus H_(2)O_(2)exhibiting a significantly boosted photo-Fenton activity toward LEV at visible light irradiation,compared to the pure ZnFe_(2)O_(4)and MIL-88A(Fe),the degradation efficiency accordingly reached up to nearly 82%and 25%within 60 min.This excellent photocatalytic performance was ascribed to the synergistic effects of the heterogeneous structure of ZnFe_(2)O_(4)and MIL-88A(Fe),whereby the efficient separation of charge carriers in the catalytic system is mutually reinforced with the efficient reduction of Fe^(3+)and Fe^(2+).Meanwhile,the degradationmechanism and intermediates of LEV during the photo-Fenton reaction process were also studied in depth through free radical burst,electron paramagnetic resonance,and mass spectrometry analyses,etc.Additionally,the ZnFe_(2)O_(4)@MIL-88A(Fe)composite catalyst displayed significant stability and ease of separation,indicating potential for the photooxidative degradation of organic pollutants.展开更多
The integration of interfacial solar steam generation and photocatalytic degradation technology has pro-vided a promising platform to simultaneously produce freshwater and degrade pollutants.However,con-structing low-...The integration of interfacial solar steam generation and photocatalytic degradation technology has pro-vided a promising platform to simultaneously produce freshwater and degrade pollutants.However,con-structing low-cost,multi-functional evaporators for treating Cr(Ⅵ)-polluted water remains challenging,and the synergistic mechanism on Cr(Ⅵ)reduction is fuzzy.Herein,we propose the combined strategy of ball milling and solution mixing for the sustainable production of Bi-MOF microrod from waste poly(ethylene terephthalate),and construct Bi-MOF-based solar evaporators for simultaneous photo-Fenton Cr(Ⅵ)reduction and freshwater production.Firstly,the evaporator comprised of Bi-MOF microrod and graphene nanosheet possesses high light absorption,efficient photothermal conversion,and good hydro-philic property.Attributing to the advantages,the hybrid evaporator exhibits the evaporation rate of 2.16 kg m^(-2) h^(-1) and evaporation efficiency of 87.5%under 1 kW m^(-2) of irradiation.When integrating with photo-Fenton reaction,the Cr(Ⅵ)reduction efficiency is 91.3%,along with the reaction kinetics of 0.0548 min^(-1),surpassing many advanced catalysts.In the outdoor freshwater production and Cr(Ⅵ)reduction,the daily accumulative water yield is 5.17 kg m^(-2) h^(-1),and the Cr(Ⅵ)reduction efficiency is 99.9%.Furthermore,we prove that the localization effect derived from the interfacial solar-driven evap-oration enhances H_(2)O_(2) activation for the photo-Fenton reduction of Cr(Ⅵ).Based on the result of density functional theory,Bi-MOF microrod provides rich active centers for H_(2)O_(2) activation to produce active sites such as e-or-O_(2).This study not only proposes a new strategy to construct multi-functional solar evaporators for freshwater production and catalytic reduction of pollutants,but also advances the chem-ical upcycling of waste polyesters.展开更多
The insufficient F(Ⅲ)/Fe(Ⅱ)cycling rate resulted from high combination of photogenerated carriers severely hinders the photo-Fenton activity.In this work,0 dimensionalα-Fe_(2)O_(3)nanoclusters decorated Ti O_(2)het...The insufficient F(Ⅲ)/Fe(Ⅱ)cycling rate resulted from high combination of photogenerated carriers severely hinders the photo-Fenton activity.In this work,0 dimensionalα-Fe_(2)O_(3)nanoclusters decorated Ti O_(2)heterojunction(FT-x)was prepared via in-situ phase transformation strategy.FT-200 exhibited the optimal photo-Fenton activity for 2,4-dichlorophenol degradation with the kinetic rate constant reaching1.0806 min^(-1)under low H_(2)O_(2)dosage(1 mmol/L),which was 126.1 and 202.8 times higher than that of Ti O_(2)andα-Fe_(2)O_(3).Radical quenching experiments and electron spin resonance spectra proved that·OH was the leading reactive specie.The enhanced photo-Fenton activity was attributed to the accelerated F(III)/Fe(II)cycling rate induced by the direct Z-Scheme charge transfer mechanism.Benefiting from the abundant·OH production,the dechlorinate ratios and mineralization ratios of multiple chlorophenol pollutants(2,4-dichlorophenol,4-chlorophenol,2,4,6-trichlorophenol)all exceeded 98%.The biotoxicity of chlorophenol wastewater was greatly reduced after the treatment by Light/H_(2)O_(2)/FT-200 system.Overall,this work constructed a low-cost and highly efficient photo-Fenton system for refractory organic wastewater treatment.展开更多
A low cycle of Fe^(2+)/Fe^(3+),additional H_(2)O_(2)use,and low mineralization efficiency have limited the wide application of Fe-MOFs.Herein,a novel Z-scheme r-MIL-88A/OV-BiOBr composites(OV-BM)with oxygen vacancies(...A low cycle of Fe^(2+)/Fe^(3+),additional H_(2)O_(2)use,and low mineralization efficiency have limited the wide application of Fe-MOFs.Herein,a novel Z-scheme r-MIL-88A/OV-BiOBr composites(OV-BM)with oxygen vacancies(OV)were fabricated by polyvinylpyrrolidone/ethylene glycol solvothermal method.The optimal OV-BM-25 showed the highest degradation efficiency of 97.8%for chloroquine phosphate(CQ)by initiat-ing H_(2)O_(2)under LED visible light irradiation within 60 min.The presence of oxygen vacancies enhanced the electron/hole separation in OV-BM composites and the electron transfer from OV-BiOBr to r-MIL-88A,driving Fe^(2+)/Fe^(3+)cycling and in-situ H_(2)O_(2)generation.Quenching experiments and EPR analysis demon-strated that O 2-,1 O 2,and e-were the main active species,inducing deamination,decarbonization,and cleavage of ring structures in CQ.The possible decomposition pathways of CQ and the ecotoxicity of in-termediates were evaluated through UPLC-MS and QSAR analysis.This study provides a theoretical basis for developing Fe-MOFs-based heterojunctions photocatalysts in a Z-scheme photo-Fenton system to treat CQ-bearing organic wastewater.展开更多
Industrial effluents from textile, tannery or printing activities often have a significant pollutant load composed of dyes that are difficult to biodegrade. These dyes pose a threat to the environment. To overcome thi...Industrial effluents from textile, tannery or printing activities often have a significant pollutant load composed of dyes that are difficult to biodegrade. These dyes pose a threat to the environment. To overcome this problem, various processes have been developed to eliminate these dyes in wastewater before their release into nature. Conventional biological or physical processes most often prove to be ineffective and expensive. It is therefore necessary to resort to other processes such as advanced oxidation processes (POA). This work therefore focuses on the study of the influence of clay in the degradation of Methylene Blue by the photo-Fenton process which is one of the advanced oxidation processes (POA), with the source of irradiation, natural light. To do this, two clays from Côte d’Ivoire referenced AB and Aga were the subject of a physicochemical and mineralogical characterization. The results showed that Aga clay is composed of 75.43% quartz, 12.72% kaolinite, 8.75% illite and 3.12% goethite and AB clay consists of 61, 36% kaolinite, 28.6% quartz and 10.10% illite. Under natural light irradiation the optimal amounts of Fenton reagents (iron: 10 mg;H2O2: 0.1 mL) were determined. Finally, the addition of clay to the photo-Fenton process made it possible to improve the degradation of the pollutant (Methylene Blue). Indeed, the yield increased from 92% for the photo-Fenton process to 98.43% with the addition of AB clay and 98.13% for the addition of Aga clay. The results of the degradation kinetics clearly show that the degradation follows the pseudo-second order kinetics with correlation coefficients greater than 0.99.展开更多
The anaerobic digestion of sludge has recently received increased interest because of the potential to transform organic matter into methane‐rich biogas. However, digested sludge, the residue produced in that process...The anaerobic digestion of sludge has recently received increased interest because of the potential to transform organic matter into methane‐rich biogas. However, digested sludge, the residue produced in that process, still contains high levels of heavy metals and other harmful substances that might make traditional disposal difficult. We have devised a facile method of converting digested sludge into a mesoporous material that acts as an effective and stable heterogeneous catalyst for the photo‐Fenton reaction. A comparison of the removal of rhodamine B under different conditions showed that FAS‐1‐350, which was synthesized by mixing the digested sludge with a 1 mol/L（NH4）2Fe（SO4）2 solution followed by calcination at 350 °C, exhibited the best catalytic activity owing to its faster reaction rate and lower degree of Fe leaching. The results indicate that Fe^（2＋）‐loaded catalysts have significant potential to act as stable and efficient heterogeneous promoters for the photo‐Fenton reaction, with better performance than Fe^3＋‐loaded catalysts because the Fe（II）/Fe（III）compounds formed in the calcination process are necessary to sustain the Fenton reaction. This protocol provides an alternative, environmentally friendly method of reusing digested sludge and demonstrates an easily synthesized mesoporous material that effectively degrades azo dyes.展开更多
文摘Solar-driven Fenton-like reactions are promising strategies for degrading pharmaceutical wastewater to address environmental challenges and antibiotic pollution.However,its efficacy is limited by suboptimal light absorption efficiency,rapid charge recombination,and inadequate interfacial charge transfer.In this study,an inorganic/organic S-scheme photo-Fenton system of pseudobrookite/carbon nitride(FTOCN)was synthesized via a hydrothermally coupled calcination process for the effective purification of tetracycline antibiotics under visible-light irradiation.The optimized FTOCN-2 heterostructure exhibits a significantly enhanced TC degradation capacity of 90%within 60 min.The rate constant of FTOCN-2 is 1.6 and 5.2 times greater than those of FTO and CN,respectively.Furthermore,FTOCN exhibits high antibacterial efficacy,highlighting its potential application in the purification of natural water.Measurements via a range of analytical techniques,including Kelvin probe force microscopy,density functional theory calculations,in situ X-ray photoelectron spectroscopy,and femtosecond transient absorption spectroscopy,corroborate the S-scheme mechanism.This study provides a novel perspective for the development of photo-Fenton systems with S-scheme heterojunctions for water purification.
基金supported by the National Key Research and Development Program of China(2020YFD1100501)Thanks zkec(www.zjkec.cc)for XRD.
文摘Fenton method combined with light to accelerate the production of free radicals from H2O2 can achieve more efficient pollutant degradation.In this paper,a novel BiOI/FeWO4 S-scheme heterojunction photocatalyst was obtained by in situ synthesis,which can activate H2O2 and degrade the organic pollutant OFC(ofloxacin)under visible light.The S-scheme charge transfer mechanism was confirmed by XPS spectroscopy,in situ KPFM and theoretical calculation.The photogenerated electrons were transferred from FeWO4 to BiOI driven by the built-in electric field and band bending,which inhibited carrier recombination and facilitated the activation of H2O2.The BiFe-5/Vis/H2O2 system degraded OFC up to 96.4%in 60 min.This study provides new systematic insights into the activation of H2O2 by S-scheme heterojunctions,which is of great significance for the treatment of antibiotic wastewater.
基金supported by the National Natural Science Foundation of China(No.22178325)Jinhua Science and Technology Plan Project.
文摘Monotonic pore size and particles inseparability of metal-organic frameworks(MOFs)caused serious effects on its light absorption ability and charge separation,restricting its application for antibiotic such as levofloxacin(LEV)degradation in water.In this study,a magnetically detachable nano-photocatalyst(ZnFe_(2)O_(4)@MIL-88A(Fe))was synthesized using a simple two-step hydrothermal technique.The morphology and microstructure analyses showed that n-type ZnFe_(2)O_(4)catalyst particleswere efficiently assembled onto the surface of MIL-88A(Fe)crystal.Photocatalytic activity studies indicated that the ZnFe_(2)O_(4)@MIL-88A(Fe)plus H_(2)O_(2)exhibiting a significantly boosted photo-Fenton activity toward LEV at visible light irradiation,compared to the pure ZnFe_(2)O_(4)and MIL-88A(Fe),the degradation efficiency accordingly reached up to nearly 82%and 25%within 60 min.This excellent photocatalytic performance was ascribed to the synergistic effects of the heterogeneous structure of ZnFe_(2)O_(4)and MIL-88A(Fe),whereby the efficient separation of charge carriers in the catalytic system is mutually reinforced with the efficient reduction of Fe^(3+)and Fe^(2+).Meanwhile,the degradationmechanism and intermediates of LEV during the photo-Fenton reaction process were also studied in depth through free radical burst,electron paramagnetic resonance,and mass spectrometry analyses,etc.Additionally,the ZnFe_(2)O_(4)@MIL-88A(Fe)composite catalyst displayed significant stability and ease of separation,indicating potential for the photooxidative degradation of organic pollutants.
基金supported by the National Natural Science Foundation of China(52373099)the Innovation and Talent Recruitment Base of New Energy Chemistry and Device(B21003)。
文摘The integration of interfacial solar steam generation and photocatalytic degradation technology has pro-vided a promising platform to simultaneously produce freshwater and degrade pollutants.However,con-structing low-cost,multi-functional evaporators for treating Cr(Ⅵ)-polluted water remains challenging,and the synergistic mechanism on Cr(Ⅵ)reduction is fuzzy.Herein,we propose the combined strategy of ball milling and solution mixing for the sustainable production of Bi-MOF microrod from waste poly(ethylene terephthalate),and construct Bi-MOF-based solar evaporators for simultaneous photo-Fenton Cr(Ⅵ)reduction and freshwater production.Firstly,the evaporator comprised of Bi-MOF microrod and graphene nanosheet possesses high light absorption,efficient photothermal conversion,and good hydro-philic property.Attributing to the advantages,the hybrid evaporator exhibits the evaporation rate of 2.16 kg m^(-2) h^(-1) and evaporation efficiency of 87.5%under 1 kW m^(-2) of irradiation.When integrating with photo-Fenton reaction,the Cr(Ⅵ)reduction efficiency is 91.3%,along with the reaction kinetics of 0.0548 min^(-1),surpassing many advanced catalysts.In the outdoor freshwater production and Cr(Ⅵ)reduction,the daily accumulative water yield is 5.17 kg m^(-2) h^(-1),and the Cr(Ⅵ)reduction efficiency is 99.9%.Furthermore,we prove that the localization effect derived from the interfacial solar-driven evap-oration enhances H_(2)O_(2) activation for the photo-Fenton reduction of Cr(Ⅵ).Based on the result of density functional theory,Bi-MOF microrod provides rich active centers for H_(2)O_(2) activation to produce active sites such as e-or-O_(2).This study not only proposes a new strategy to construct multi-functional solar evaporators for freshwater production and catalytic reduction of pollutants,but also advances the chem-ical upcycling of waste polyesters.
基金supported by the National Key Research and Development Program of China(No.2023YFE0100900)the National Outstanding Youth Science Fund Project of National Natural Science Foundation of China(No.51522805)。
文摘The insufficient F(Ⅲ)/Fe(Ⅱ)cycling rate resulted from high combination of photogenerated carriers severely hinders the photo-Fenton activity.In this work,0 dimensionalα-Fe_(2)O_(3)nanoclusters decorated Ti O_(2)heterojunction(FT-x)was prepared via in-situ phase transformation strategy.FT-200 exhibited the optimal photo-Fenton activity for 2,4-dichlorophenol degradation with the kinetic rate constant reaching1.0806 min^(-1)under low H_(2)O_(2)dosage(1 mmol/L),which was 126.1 and 202.8 times higher than that of Ti O_(2)andα-Fe_(2)O_(3).Radical quenching experiments and electron spin resonance spectra proved that·OH was the leading reactive specie.The enhanced photo-Fenton activity was attributed to the accelerated F(III)/Fe(II)cycling rate induced by the direct Z-Scheme charge transfer mechanism.Benefiting from the abundant·OH production,the dechlorinate ratios and mineralization ratios of multiple chlorophenol pollutants(2,4-dichlorophenol,4-chlorophenol,2,4,6-trichlorophenol)all exceeded 98%.The biotoxicity of chlorophenol wastewater was greatly reduced after the treatment by Light/H_(2)O_(2)/FT-200 system.Overall,this work constructed a low-cost and highly efficient photo-Fenton system for refractory organic wastewater treatment.
基金sponsored by the Science&Technology Innovation Action Plan of Shanghai(Nos.20230742100 and 21230714000)the Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste.
文摘A low cycle of Fe^(2+)/Fe^(3+),additional H_(2)O_(2)use,and low mineralization efficiency have limited the wide application of Fe-MOFs.Herein,a novel Z-scheme r-MIL-88A/OV-BiOBr composites(OV-BM)with oxygen vacancies(OV)were fabricated by polyvinylpyrrolidone/ethylene glycol solvothermal method.The optimal OV-BM-25 showed the highest degradation efficiency of 97.8%for chloroquine phosphate(CQ)by initiat-ing H_(2)O_(2)under LED visible light irradiation within 60 min.The presence of oxygen vacancies enhanced the electron/hole separation in OV-BM composites and the electron transfer from OV-BiOBr to r-MIL-88A,driving Fe^(2+)/Fe^(3+)cycling and in-situ H_(2)O_(2)generation.Quenching experiments and EPR analysis demon-strated that O 2-,1 O 2,and e-were the main active species,inducing deamination,decarbonization,and cleavage of ring structures in CQ.The possible decomposition pathways of CQ and the ecotoxicity of in-termediates were evaluated through UPLC-MS and QSAR analysis.This study provides a theoretical basis for developing Fe-MOFs-based heterojunctions photocatalysts in a Z-scheme photo-Fenton system to treat CQ-bearing organic wastewater.
文摘Industrial effluents from textile, tannery or printing activities often have a significant pollutant load composed of dyes that are difficult to biodegrade. These dyes pose a threat to the environment. To overcome this problem, various processes have been developed to eliminate these dyes in wastewater before their release into nature. Conventional biological or physical processes most often prove to be ineffective and expensive. It is therefore necessary to resort to other processes such as advanced oxidation processes (POA). This work therefore focuses on the study of the influence of clay in the degradation of Methylene Blue by the photo-Fenton process which is one of the advanced oxidation processes (POA), with the source of irradiation, natural light. To do this, two clays from Côte d’Ivoire referenced AB and Aga were the subject of a physicochemical and mineralogical characterization. The results showed that Aga clay is composed of 75.43% quartz, 12.72% kaolinite, 8.75% illite and 3.12% goethite and AB clay consists of 61, 36% kaolinite, 28.6% quartz and 10.10% illite. Under natural light irradiation the optimal amounts of Fenton reagents (iron: 10 mg;H2O2: 0.1 mL) were determined. Finally, the addition of clay to the photo-Fenton process made it possible to improve the degradation of the pollutant (Methylene Blue). Indeed, the yield increased from 92% for the photo-Fenton process to 98.43% with the addition of AB clay and 98.13% for the addition of Aga clay. The results of the degradation kinetics clearly show that the degradation follows the pseudo-second order kinetics with correlation coefficients greater than 0.99.
基金supported by the National Key Technology Research&Development Program of China(2014BAL02B02)the National Natural Science Foundation of China(51578397)~~
文摘The anaerobic digestion of sludge has recently received increased interest because of the potential to transform organic matter into methane‐rich biogas. However, digested sludge, the residue produced in that process, still contains high levels of heavy metals and other harmful substances that might make traditional disposal difficult. We have devised a facile method of converting digested sludge into a mesoporous material that acts as an effective and stable heterogeneous catalyst for the photo‐Fenton reaction. A comparison of the removal of rhodamine B under different conditions showed that FAS‐1‐350, which was synthesized by mixing the digested sludge with a 1 mol/L（NH4）2Fe（SO4）2 solution followed by calcination at 350 °C, exhibited the best catalytic activity owing to its faster reaction rate and lower degree of Fe leaching. The results indicate that Fe^（2＋）‐loaded catalysts have significant potential to act as stable and efficient heterogeneous promoters for the photo‐Fenton reaction, with better performance than Fe^3＋‐loaded catalysts because the Fe（II）/Fe（III）compounds formed in the calcination process are necessary to sustain the Fenton reaction. This protocol provides an alternative, environmentally friendly method of reusing digested sludge and demonstrates an easily synthesized mesoporous material that effectively degrades azo dyes.
