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 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
Both citrate and hypophosphite in aqueous solution were degraded by advanced oxidation processes （Fe^2＋/H2O2, UV/Fe^2＋/H2O2, and electrolysis/Fe^2＋/H2O2） in this study. Comparison of these techniques in oxidation...Both citrate and hypophosphite in aqueous solution were degraded by advanced oxidation processes （Fe^2＋/H2O2, UV/Fe^2＋/H2O2, and electrolysis/Fe^2＋/H2O2） in this study. Comparison of these techniques in oxidation efficiency was undertaken. It was found that Fenton process could not completely degrade citrate in the presence of hypophosphite since it caused a series inhibition. Therefore, UV light （photo-Fenton） or electron current （electro-Fenton） was applied to improve the degradation efficiency of the Fenton process. Results showed that both photo-Fenton and electro-Fenton processes could overcome the inhibition of hypophosphite, especially the electro-Fenton.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 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.
基金The authors thank the "National" Science Council, Taiwan, China for financially supporting (No. NSC95- 2211-E-006-032).
文摘Both citrate and hypophosphite in aqueous solution were degraded by advanced oxidation processes （Fe^2＋/H2O2, UV/Fe^2＋/H2O2, and electrolysis/Fe^2＋/H2O2） in this study. Comparison of these techniques in oxidation efficiency was undertaken. It was found that Fenton process could not completely degrade citrate in the presence of hypophosphite since it caused a series inhibition. Therefore, UV light （photo-Fenton） or electron current （electro-Fenton） was applied to improve the degradation efficiency of the Fenton process. Results showed that both photo-Fenton and electro-Fenton processes could overcome the inhibition of hypophosphite, especially the electro-Fenton.
