Photocatalytic molecular oxygen(O2)activation provides a sustainable approach to produce singlet oxygen(1O2)for organic contaminants detoxification.However,the charge carriers-involved pathway usually suffers...Photocatalytic molecular oxygen(O2)activation provides a sustainable approach to produce singlet oxygen(1O2)for organic contaminants detoxification.However,the charge carriers-involved pathway usually suffers from unsatisfactory1O2production efficiency owing to energy loss caused by photogenerated hole-mediated superoxide species(·O2-)oxidation.If the photoinduced species could be directly extracted onto photocatalysts surface rather than completely separated into electron and holes,traditional built-in electric field-triggering charge-carriers extraction process might be circumvented,promoting the electroneutral excitons-mediated1O2production.Herein,we demonstrate that introducing sulfate ions on bismuth oxybromide surface([SO4]-BiOBr)using a facile photoetching-coordination strategy can regulate its steric hindrance and surface excitonic states.Benefiting from the energy gradient from the bulk to surface excitonic states,[SO4]-BiOBr exhibits extremely high-efficiency bulk exciton extraction performance.Different from the counterparts favoring the O2chemisorption via a side-on mode,[SO4]-BiOBr with larger steric hindrance preferentially transfers the energy of long-lived excitons to physically absorbed O2,resulting in the photocatalytically generated reactive oxygen species(ROS)switching from·O2-to1O2and thereby boosting the dechlorination and degradation of 4-chlorophenol(4-CP).This study reveals the pivotal effect of surface modification on regulating the excitonic processes of semiconductors for efficient1O2photosynthesis and subsequent wastewater purification.展开更多
Direct synthesis of dimethyl carbonate(DMC)from CO2 is critical for achieving carbon neutrality,yet the sluggish formation and conversion of the key*CH₃OCOO intermediate-due to the difficulty of C-O coupling-limit ...Direct synthesis of dimethyl carbonate(DMC)from CO2 is critical for achieving carbon neutrality,yet the sluggish formation and conversion of the key*CH₃OCOO intermediate-due to the difficulty of C-O coupling-limit high DMC yields.Herein,we developed a boric acid-assisted recrystallization strategy to fabricate grain-boundary-rich CeO2 hollow nanospheres,which serve as an efficient catalyst for CO2 to DMC synthesis.The introduction of grain-boundary(GBs)induced the electron redistribution,which led a decrease in the electron density of bulk Ce ions and created a localized electron-rich region at homogeneous interface.This unique electronic landscape promoted reactive methoxy formation and stronger CO2 adsorption,thereby enabling more efficient coupling of*CH3O and*CO2 to form the*CH3OCOO.Concurrently,the enhanced CO2 adsorption facilitated the dissociation of*CH3OCOO and subsequent DMC formation.As a result,the 4%BCeO2-GBs achieved an advantageous DMC yield of 19.8 mmol/g.In the assistance of dehydrating agent,the catalyst delivered a remarkable 264.2 mmol/g DMC yield and 7.12%methanol conversion,which was 32 times higher than commercial CeO2.This study elucidated the intrinsic mechanisms governing*CH3OCOO intermediate behavior and offers valuable guidance for CO2 converting into high-value organic chemicals.展开更多
This study presents the successful synthesis of a novel Z-scheme heterojunction composite film consisting of Ag/Bi2MoO6/BiOBr through electrochemical processes and ionexchange techniques,followed by the photodep...This study presents the successful synthesis of a novel Z-scheme heterojunction composite film consisting of Ag/Bi2MoO6/BiOBr through electrochemical processes and ionexchange techniques,followed by the photodeposition of noble metal silver(Ag)onto the composite structure.The catalytic efficiency of semiconductor photocatalysts is greatly improved by utilizing the localized surface plasmon resonance(LSPR)effect observed in Ag nanoparticles(NPs).Furthermore,the noble metal Ag serves as an intermediary bridge facilitating charge transfer between Bi2MoO6and BiOBr,while the formation of a Schottky barrier effectively inhibits the recombination of photo-generated electron-hole pairs.As a result,the Ag-deposited Bi2MoO6/BiOBr film exhibits superior photocatalytic performance in the reduction of CO2compared to its unmodified counterpart.Our experimental results indicate a non-linear relationship between Ag deposition and the efficiency of photocatalytic CO2reduction to CO,characterized by an initial increase in efficiency followed by a decline.The optimized 1.5%-Ag/Bi2MoO6/BiOBr film demonstrates exceptional photocatalytic activity,attaining a CO production rate of 13.65μmol/(g·h).This research explores the fundamental mechanisms that lead to improved photocatalytic CO2reduction capabilities of the Ag/Bi2MoO6/BiOBr film.Our research offers important perspectives for the thoughtful design and production of highly efficient photocatalysts,which are essential for advancing sustainable energy solutions.展开更多
The restricted capture of visible light and high-speed electron-hole complexation efficiency of BiOBr impose limitations on its CO2 reduction photocatalytic activity.In this study,we successfully doped Eu into BiOB...The restricted capture of visible light and high-speed electron-hole complexation efficiency of BiOBr impose limitations on its CO2 reduction photocatalytic activity.In this study,we successfully doped Eu into BiOBr,which facilitates the catalytic reduction ability of carbon dioxide to yield carbon monoxide.Surface oxygen vacancies were introduced on BiOBr after Eu-doping.The Eu-BiOBr possesses high visible light absorption range and low photoelectron-hole recombination rate.In the absence of sacrificial agents,the best performance of photocatalytic reduction of CO2 to CO for Eu-BiOBr is achieved at a doping amount of 3%Eu(in mass fraction wt%).The amount of CO generated by 3%Eu-BiOBr is 22.3 mol/(g·h),which is 10 times greater than that of single BiOBr(2.2μmol/(g·h)).In conclusion,this study provides important reference for future research on catalysts for the reduction of carbon dioxide.展开更多
The excessive use of pesticides has exacerbated environmental pollution due to herbicide residues,while their persistent toxicity poses serious challenges to global ecological security.A magnetically recyclable CoFe_(...The excessive use of pesticides has exacerbated environmental pollution due to herbicide residues,while their persistent toxicity poses serious challenges to global ecological security.A magnetically recyclable CoFe2O4/BiOBr S-scheme heterojunctions was prepared by microwave-assisted co-precipitation method for photocatalytic degradation of Diuron(DUR) in water.The formation of S-scheme heterojunction enhances electron transfer and charge separation,which was demonstrated by free radical trapping,electrochemical experiments,and DFT calculations.The magnetic CoFe2O4/BiOBr catalysts can achieve 99.9 %removal of diuron in 50 min under visible light irradiation.Furthermore,the system maintains stable performance across a broad p H range(3-9),enabling adaptation to diverse water environments,effective elimination of multiple pollutants,and strong resistance to ionic interference.Using magnetic recovery,CoFe2O4/BiOBr exhibits a high removal rate of 99 % and a markedly low ion leaching rate(<20 μg/L) after six cycles photocatalytic process,confirming its excellent stability and durability.According to HPLCQTOF-MS and DFT calculation,the main ways of DUR degradation include dechlorinated hydroxylation,dealkylation and hydroxylation of aromatic ring and side chain.Toxicity analysis showed that the toxicity of the intermediates generated during degradation was generally lower than that of DUR.The magnetic CoFe2O4/BiOBr S-scheme heterojunction developed in this study exhibits excellent photocatalytic performance,high applicability,good stability,and durability,providing an effective magnetic for the removal of refractory pollutants.展开更多
CO2 photoreduction into carbon-based chemicals has been considered as an appropriate way to alleviate the energy issue and greenhouse effect.Herein,the 5,10,15,20-tetra(4-carboxyphenyl)porphyrin cobalt(II)(CoTCPP)h...CO2 photoreduction into carbon-based chemicals has been considered as an appropriate way to alleviate the energy issue and greenhouse effect.Herein,the 5,10,15,20-tetra(4-carboxyphenyl)porphyrin cobalt(II)(CoTCPP)has been integrated with BiOBr microspheres and formed the CoTCPP/BiOBr composite.The as-prepared CoTCPP/BiOBr-2 composite shows optimized photocatalytic performance for CO2 conversion into CO and CH4 upon irradiation with 300 W Xe lamp,which is 2.03 and 2.58 times compared to that of BiOBr,respectively.The introduced CoTCPP significantly enhanced light absorption properties,promoted rapid separation of photogenerated carriers and boosted the chemisorption of CO2 molecules.The metal Co2+ at the center of the porphyrin molecules also acts as adsorption center for CO2 molecules,accelerating the CO2 conversion into CO and CH4.The possible mechanism of CO2 photoreduction was explored by in-situ FT-IR spectra.This work offers a new possibility for the preparation of advanced photocatalysts.展开更多
The establishment of S-scheme heterojunctions has arisen as a promising strategy for the advancement of efficient photocatalytic systems with superior charge separation and redox ability,specifically for H2O2pro...The establishment of S-scheme heterojunctions has arisen as a promising strategy for the advancement of efficient photocatalytic systems with superior charge separation and redox ability,specifically for H2O2production.In this investigation,an innovative 2D/2D g-C3N4/BiOBr S-scheme heterojunction was meticulously engineered through an in situ growth methodology.The synthetic composites exhibit boosted H2O2production activity,achieving a peak generation rate of 392μmol L-1h-1,approximately 8.7-fold and 2.1-fold increase over the pristine BiOBr and g-C3N4,respectively.Such a superior activity should be attributed to the highly efficient charge separation and migration mechanisms,along with the sustained robust redox capability of S-scheme heterostructure,which are verified by time-resolved photoluminescence spectroscopy,photocurrent test and electron paramagnetic resonance measurements.Furthermore,the interfacial electric field induced S-scheme charge transfer mechanism between g-C3N4and BiOBr is systematically certificated by in situ irradiated X-ray photoelectron spectroscopy and density functional theory calculation.This research offers a comprehensive protocol for the systematic development and construction of highly efficient S-scheme heterojunction photocatalysts,specifically tailored for enhanced H2O2production.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant Nos.22306119 and 22206124)the Natural Science Foundation of Sichuan Province(Grant No.2025ZNSFSC0954)+2 种基金Sichuan Science and Technology Program(Grant No.2024NSFTD0014)the Key R&D Program of Heilongjiang Province(Grant No.2023ZX02C01)Sichuan University Interdisciplinary Innovation Fund and the Fundamental Research Funds for the Central Universities(Grant No.YJ202460)。
摘要Photocatalytic molecular oxygen(O2)activation provides a sustainable approach to produce singlet oxygen(1O2)for organic contaminants detoxification.However,the charge carriers-involved pathway usually suffers from unsatisfactory1O2production efficiency owing to energy loss caused by photogenerated hole-mediated superoxide species(·O2-)oxidation.If the photoinduced species could be directly extracted onto photocatalysts surface rather than completely separated into electron and holes,traditional built-in electric field-triggering charge-carriers extraction process might be circumvented,promoting the electroneutral excitons-mediated1O2production.Herein,we demonstrate that introducing sulfate ions on bismuth oxybromide surface([SO4]-BiOBr)using a facile photoetching-coordination strategy can regulate its steric hindrance and surface excitonic states.Benefiting from the energy gradient from the bulk to surface excitonic states,[SO4]-BiOBr exhibits extremely high-efficiency bulk exciton extraction performance.Different from the counterparts favoring the O2chemisorption via a side-on mode,[SO4]-BiOBr with larger steric hindrance preferentially transfers the energy of long-lived excitons to physically absorbed O2,resulting in the photocatalytically generated reactive oxygen species(ROS)switching from·O2-to1O2and thereby boosting the dechlorination and degradation of 4-chlorophenol(4-CP).This study reveals the pivotal effect of surface modification on regulating the excitonic processes of semiconductors for efficient1O2photosynthesis and subsequent wastewater purification.
摘要Direct synthesis of dimethyl carbonate(DMC)from CO2 is critical for achieving carbon neutrality,yet the sluggish formation and conversion of the key*CH₃OCOO intermediate-due to the difficulty of C-O coupling-limit high DMC yields.Herein,we developed a boric acid-assisted recrystallization strategy to fabricate grain-boundary-rich CeO2 hollow nanospheres,which serve as an efficient catalyst for CO2 to DMC synthesis.The introduction of grain-boundary(GBs)induced the electron redistribution,which led a decrease in the electron density of bulk Ce ions and created a localized electron-rich region at homogeneous interface.This unique electronic landscape promoted reactive methoxy formation and stronger CO2 adsorption,thereby enabling more efficient coupling of*CH3O and*CO2 to form the*CH3OCOO.Concurrently,the enhanced CO2 adsorption facilitated the dissociation of*CH3OCOO and subsequent DMC formation.As a result,the 4%BCeO2-GBs achieved an advantageous DMC yield of 19.8 mmol/g.In the assistance of dehydrating agent,the catalyst delivered a remarkable 264.2 mmol/g DMC yield and 7.12%methanol conversion,which was 32 times higher than commercial CeO2.This study elucidated the intrinsic mechanisms governing*CH3OCOO intermediate behavior and offers valuable guidance for CO2 converting into high-value organic chemicals.
基金Supported by the National Natural Science Foundation of China(21978196)Natural Science Foundation of Shanxi Province(201801D211008,202403021211018)+1 种基金Shanxi Provincial Education Department(S202413597023)Jincheng High Efficiency Conversion and Utilization Technology Innovation Center of CO2 Energy and Biomass Energy。
摘要This study presents the successful synthesis of a novel Z-scheme heterojunction composite film consisting of Ag/Bi2MoO6/BiOBr through electrochemical processes and ionexchange techniques,followed by the photodeposition of noble metal silver(Ag)onto the composite structure.The catalytic efficiency of semiconductor photocatalysts is greatly improved by utilizing the localized surface plasmon resonance(LSPR)effect observed in Ag nanoparticles(NPs).Furthermore,the noble metal Ag serves as an intermediary bridge facilitating charge transfer between Bi2MoO6and BiOBr,while the formation of a Schottky barrier effectively inhibits the recombination of photo-generated electron-hole pairs.As a result,the Ag-deposited Bi2MoO6/BiOBr film exhibits superior photocatalytic performance in the reduction of CO2compared to its unmodified counterpart.Our experimental results indicate a non-linear relationship between Ag deposition and the efficiency of photocatalytic CO2reduction to CO,characterized by an initial increase in efficiency followed by a decline.The optimized 1.5%-Ag/Bi2MoO6/BiOBr film demonstrates exceptional photocatalytic activity,attaining a CO production rate of 13.65μmol/(g·h).This research explores the fundamental mechanisms that lead to improved photocatalytic CO2reduction capabilities of the Ag/Bi2MoO6/BiOBr film.Our research offers important perspectives for the thoughtful design and production of highly efficient photocatalysts,which are essential for advancing sustainable energy solutions.
基金Project supported by the National Natural Science Foundation of China(22302089,22066017,22462033)Jiangxi Province Natural Science Foundation(20242BAB20183)+1 种基金the Open Fund of Jiangxi Province Key Laboratory of Synthetic Chemistry(JXSC202003)Jiangxi Province“Double Thousand Plan”Project(jxsq2019201007,jxsq2020102027)。
摘要The restricted capture of visible light and high-speed electron-hole complexation efficiency of BiOBr impose limitations on its CO2 reduction photocatalytic activity.In this study,we successfully doped Eu into BiOBr,which facilitates the catalytic reduction ability of carbon dioxide to yield carbon monoxide.Surface oxygen vacancies were introduced on BiOBr after Eu-doping.The Eu-BiOBr possesses high visible light absorption range and low photoelectron-hole recombination rate.In the absence of sacrificial agents,the best performance of photocatalytic reduction of CO2 to CO for Eu-BiOBr is achieved at a doping amount of 3%Eu(in mass fraction wt%).The amount of CO generated by 3%Eu-BiOBr is 22.3 mol/(g·h),which is 10 times greater than that of single BiOBr(2.2μmol/(g·h)).In conclusion,this study provides important reference for future research on catalysts for the reduction of carbon dioxide.
基金supported by the National Natural Science Foundation of China (No.52370174)the Natural Science Foundation of Shandong Province,China (No.ZR2022ME128)Special Projects in Key Areas of Colleges and Universities in Guangdong Province (No.2023ZDZX4050)。
摘要The excessive use of pesticides has exacerbated environmental pollution due to herbicide residues,while their persistent toxicity poses serious challenges to global ecological security.A magnetically recyclable CoFe2O4/BiOBr S-scheme heterojunctions was prepared by microwave-assisted co-precipitation method for photocatalytic degradation of Diuron(DUR) in water.The formation of S-scheme heterojunction enhances electron transfer and charge separation,which was demonstrated by free radical trapping,electrochemical experiments,and DFT calculations.The magnetic CoFe2O4/BiOBr catalysts can achieve 99.9 %removal of diuron in 50 min under visible light irradiation.Furthermore,the system maintains stable performance across a broad p H range(3-9),enabling adaptation to diverse water environments,effective elimination of multiple pollutants,and strong resistance to ionic interference.Using magnetic recovery,CoFe2O4/BiOBr exhibits a high removal rate of 99 % and a markedly low ion leaching rate(<20 μg/L) after six cycles photocatalytic process,confirming its excellent stability and durability.According to HPLCQTOF-MS and DFT calculation,the main ways of DUR degradation include dechlorinated hydroxylation,dealkylation and hydroxylation of aromatic ring and side chain.Toxicity analysis showed that the toxicity of the intermediates generated during degradation was generally lower than that of DUR.The magnetic CoFe2O4/BiOBr S-scheme heterojunction developed in this study exhibits excellent photocatalytic performance,high applicability,good stability,and durability,providing an effective magnetic for the removal of refractory pollutants.
基金financially supported by National Natural Science Foundation of China(Nos.22138011,22108106 and 22108108)China Postdoctoral Science Foundation(Nos.2022M721380 and 2020M680065)Hong Kong Scholar Program(XJ2021021).
摘要CO2 photoreduction into carbon-based chemicals has been considered as an appropriate way to alleviate the energy issue and greenhouse effect.Herein,the 5,10,15,20-tetra(4-carboxyphenyl)porphyrin cobalt(II)(CoTCPP)has been integrated with BiOBr microspheres and formed the CoTCPP/BiOBr composite.The as-prepared CoTCPP/BiOBr-2 composite shows optimized photocatalytic performance for CO2 conversion into CO and CH4 upon irradiation with 300 W Xe lamp,which is 2.03 and 2.58 times compared to that of BiOBr,respectively.The introduced CoTCPP significantly enhanced light absorption properties,promoted rapid separation of photogenerated carriers and boosted the chemisorption of CO2 molecules.The metal Co2+ at the center of the porphyrin molecules also acts as adsorption center for CO2 molecules,accelerating the CO2 conversion into CO and CH4.The possible mechanism of CO2 photoreduction was explored by in-situ FT-IR spectra.This work offers a new possibility for the preparation of advanced photocatalysts.
摘要The establishment of S-scheme heterojunctions has arisen as a promising strategy for the advancement of efficient photocatalytic systems with superior charge separation and redox ability,specifically for H2O2production.In this investigation,an innovative 2D/2D g-C3N4/BiOBr S-scheme heterojunction was meticulously engineered through an in situ growth methodology.The synthetic composites exhibit boosted H2O2production activity,achieving a peak generation rate of 392μmol L-1h-1,approximately 8.7-fold and 2.1-fold increase over the pristine BiOBr and g-C3N4,respectively.Such a superior activity should be attributed to the highly efficient charge separation and migration mechanisms,along with the sustained robust redox capability of S-scheme heterostructure,which are verified by time-resolved photoluminescence spectroscopy,photocurrent test and electron paramagnetic resonance measurements.Furthermore,the interfacial electric field induced S-scheme charge transfer mechanism between g-C3N4and BiOBr is systematically certificated by in situ irradiated X-ray photoelectron spectroscopy and density functional theory calculation.This research offers a comprehensive protocol for the systematic development and construction of highly efficient S-scheme heterojunction photocatalysts,specifically tailored for enhanced H2O2production.