Photocatalytic solar energy conversion has drawn increasing attention,which holds great potential to deal with the energy crisis and environmental issues.As a typical semiconductor photocatalyst,graphite nitrogen carb...Photocatalytic solar energy conversion has drawn increasing attention,which holds great potential to deal with the energy crisis and environmental issues.As a typical semiconductor photocatalyst,graphite nitrogen carbon(g-C_(3)N_(4))has been widely utilized owing to its nontoxicity and easy preparation properties.However,pristine g-C_(3)N_(4) also faces the limitations of unsatisfactory light absorption,few active sites,and a rapid combination of photo-induced charge.To further optimize the photochemical catalytic performance of g-C_(3)N_(4),tremendous efforts were devoted to modifying g-C_(3)N_(4),including morphological regulation,element doping,and heterogeneous engineering.Some considerable progress has been achieved in g-C_(3)N_(4)-based photocatalytic hydrogen generation(PHE)from water splitting,photocatalytic carbon dioxide reduction(PCR),photocatalytic nitrogen reduction(PNR),photocatalytic removal of pollutants,and photocatalytic bacteria elimination.However,a frontier and comprehensive summary of g-C_(3)N_(4)-based photocatalysis is rarely reported.Herein,we provide an all-inclusive and updated investigation of the recent advances in modification methods of g-C_(3)N_(4) and photocatalytic reactions based on g-C_(3)N_(4) in the past five years.This conclusive remark may provide a new physical insight into the development of g-C_(3)N_(4)-based solar energy conversion.展开更多
Electrocatalytic reduction of nitrate pollutants to produce ammonia offers an effective approach to realizing the artificial nitrogen cycle and replacing the energyintensive Haber-Bosch process.Nitrite is an important...Electrocatalytic reduction of nitrate pollutants to produce ammonia offers an effective approach to realizing the artificial nitrogen cycle and replacing the energyintensive Haber-Bosch process.Nitrite is an important intermediate product in the reduction of nitrate to ammonia.Therefore,the mechanism of converting nitrite into ammonia warrants further investigation.Molecular cobalt catalysts are regarded as promising for nitrite reduction reactions(NO_(2)^(−)RR).However,designing and controlling the coordination environment of molecular catalysts is crucial for studying the mechanism of NO_(2)^(−)RR and catalyst design.Herein,we develop a molecular platform of cobalt porphyrin with three coordination microenvironments(Co-N_(3)X_(1),X=N,O,S).Electrochemical experiments demonstrate that cobalt porphyrin with O coordination(CoOTPP)exhibits the lowest onset potential and the highest activity for NO_(2)^(−)RR in ammonia production.Under neutral,nonbuffered conditions over a wide potential range(−1.0 to−1.5 V versus AgCl/Ag),the Faradaic efficiency of nearly 90%for ammonia was achieved and reached 94.5%at−1.4 V versus AgCl/Ag,with an ammonia yield of 6,498μgh^(−1)and a turnover number of 22,869 at−1.5V versus AgCl/Ag.In situ characterization and density functional theory calculations reveal that modulating the coordination environment alters the electron transfer mode of the cobalt active center and the charge redistribution caused by the break of the ligand field.Therefore,this results in enhanced electrochemical activity for NO_(2)^(−)RR in ammonia production.This study provides valuable guidance for designing adjustments to the coordination environment of molecular catalysts to enhance catalytic activity.展开更多
Metal-organic frameworks(MOFs)have shown excellent adsorption and degradation performance towards different kinds of dyes but suffer problems in the desorption process,where adsorbates cannot be completely removed and...Metal-organic frameworks(MOFs)have shown excellent adsorption and degradation performance towards different kinds of dyes but suffer problems in the desorption process,where adsorbates cannot be completely removed and may cause energy waste or secondary pollution by the repeated washing with eluent,as well as their relatively weak stability in aqueous solutions.Thus,it is very attractive to integrate MOFs with active ingredients to prepare MOF-based composites with dye adsorption and degradation ability.The reported fabrication method of MOF@TiO_(2) usually involves high crystallization temperature or contains acid or base additives,which are unfriendly to MOF structures.Here,we report the design of MOF@TiO_(2) core-shell nanostructures via a surfactant-free amorphous TiO_(2) coating followed by water-assisted crystallization at a low temperature(100℃)below the decomposition temperature of most MOFs.Owing to the mild crystallization conditions,MOF cores are maintained and TiO_(2) shells crystallize to an active anatase phase.The obtained MOF@TiO_(2) core-shell nanostructures showed excellent dye removal efficiency and stability for anionic dyes,which can remove 98% dye after five adsorption and photodegradation cycles due to the synergistic effect of MOF cores and TiO_(2) shells.The design concept and synthetic strategy via the water-assisted crystallization method for labile MOF materials encapsulated in functional TiO_(2) shells may be used to construct other multifunctional MOF core-shell nanostructures,broadening their applications in diverse fields.展开更多
The fabrication of photocatalysts to achieve efficient utilization of renewable solar energy has attracted broad interest.Herein,a plasmonic spiky TiO_(2)/Au nanorod(NR)nanohybrid was prepared by in situ nucleation an...The fabrication of photocatalysts to achieve efficient utilization of renewable solar energy has attracted broad interest.Herein,a plasmonic spiky TiO_(2)/Au nanorod(NR)nanohybrid was prepared by in situ nucleation and growth of spiky TiO_(2)in AuNR colloidal solution.The spiky TiO_(2)/AuNR nanohybrids demonstrated enhanced hydrogen evolution activity and photocurrent generation under both visible light and simulated solar light irradiation as compared to bare spiky TiO_(2)nanoparticles and commercial TiO_(2).Specifically,the spiky nanohybrids displayed a high H2 production rate of 1.81 mmol g^(−1)h^(−1)under simulated solar light irradiation,which is 1.7 times higher than that of TiO_(2)/Au nanosphere nanohybrids,and remain stable for three cycles.The improved photocatalytic H2 evolution demonstrated by the nanohybrids can be ascribed to the coupling effect of the AuNRs and the unique spiky structure.Furthermore,the charge transfer process during H2 evolution was investigated by photocurrent and electrochemical impendence spectroscopy(EIS)measurements.A fast and stable photocurrent was observed for the spiky TiO_(2)/AuNR nanohybrid photoelectrode under both visible light and simulated solar light irradiation,while the EIS plots indicate a rapid charge transfer within the nanohybrids.Such a nanohybrid with a bioinspired structure will afford new insights for the fabrication of novel photocatalysts.展开更多
A supercapacitor electrode has been fabricated from macroscopic porous MnO2 aerogels,and has demonstrated an enhanced specific capacitance,a high rate capability and excellent cycling durability.The improvement of sup...A supercapacitor electrode has been fabricated from macroscopic porous MnO2 aerogels,and has demonstrated an enhanced specific capacitance,a high rate capability and excellent cycling durability.The improvement of supercapacitive performance can be attributed to the macro interconnected channels in the aerogel structure,which can not only facilitate mass transfer and reduce dead volume,but also provide an additional benefit of relieving stress.展开更多
Photocatalytic hydrogen evolution(PHE)is one of the most promising methods for clean energy production.However,current photocatalysts are still challenged by limited light absorption and rapid recombination of photoge...Photocatalytic hydrogen evolution(PHE)is one of the most promising methods for clean energy production.However,current photocatalysts are still challenged by limited light absorption and rapid recombination of photogenerated carriers.Constructing defects can effectively broaden light absorption and promote charge separation and transfer.The interface between heterogeneous catalysts is prone to generating multi-component active centers to facilitate the activation of reactants for enhanced catalytic activity.In this report,the combination of defective TiO_(2)and ZnIn_(2)S_(4)of sulfur-rich vacancies(TiO_(2)@ZIS)was developed,which achieved an optimized PHE rate of 9.63 mmol g^(-1)h^(-1).After loading 1.0 wt%Pt cocatalyst,TiO_(2)@ZIS exhibits the apparently-raised PHE rate of 83.41 mmol g^(-1)h^(-1)in the presence of triethanolamine(TEOA)as the sacrificial agent.Theoretical calculation and experimental results reveal that the remarkable hydrogen(H_(2))evolution performance is contributed by the unique Z-scheme charge transfer pathway,which reduces energy loss during charge transfer and facilitates the kinetics of surface H_(2)evolution.This report provides valuable insights into designing and engineering defective materials for solar-driven energy conversion.展开更多
基金supported by Jilin youth growth science and technology plan project(No.20220508019RC)the“Interdisciplinary integration and innovation”project of Jilin University in 2021(No.JLUXKJC2021QZ06)+6 种基金the Natural Science Foundation of Jilin Province(No.SKL202302017)the National Natural Science Foundation of China(Nos.22279041,22301099,and 82302277)the National Key Research and Development Program of China(No.2022YFC2105800)the 111 Project(No.B17020)the Science and Technology Innovation Program of Hunan Province(No.2022RC1232)Provincial Natural Science Foundation of Hunan(Grant No.2023JJ40087)Research Foundation of Education Bureau of Hunan Province(No.22B0896).
文摘Photocatalytic solar energy conversion has drawn increasing attention,which holds great potential to deal with the energy crisis and environmental issues.As a typical semiconductor photocatalyst,graphite nitrogen carbon(g-C_(3)N_(4))has been widely utilized owing to its nontoxicity and easy preparation properties.However,pristine g-C_(3)N_(4) also faces the limitations of unsatisfactory light absorption,few active sites,and a rapid combination of photo-induced charge.To further optimize the photochemical catalytic performance of g-C_(3)N_(4),tremendous efforts were devoted to modifying g-C_(3)N_(4),including morphological regulation,element doping,and heterogeneous engineering.Some considerable progress has been achieved in g-C_(3)N_(4)-based photocatalytic hydrogen generation(PHE)from water splitting,photocatalytic carbon dioxide reduction(PCR),photocatalytic nitrogen reduction(PNR),photocatalytic removal of pollutants,and photocatalytic bacteria elimination.However,a frontier and comprehensive summary of g-C_(3)N_(4)-based photocatalysis is rarely reported.Herein,we provide an all-inclusive and updated investigation of the recent advances in modification methods of g-C_(3)N_(4) and photocatalytic reactions based on g-C_(3)N_(4) in the past five years.This conclusive remark may provide a new physical insight into the development of g-C_(3)N_(4)-based solar energy conversion.
基金National Key Research and Development Program of China,Grant/Award Number:2022YFC2105800National Natural Science Foundation of China,Grant/Award Numbers:21901084,21905106,22279041+2 种基金Higher Education Discipline Innovation Project,Grant/Award Number:B17020Specific Research Fund of the Innovation Platform for Academicians of Hainan Province,China,Grant/Award Number:YSPTZX202321Natural Science Foundation of Jilin Province,Grant/Award Number:SKL202302017.
文摘Electrocatalytic reduction of nitrate pollutants to produce ammonia offers an effective approach to realizing the artificial nitrogen cycle and replacing the energyintensive Haber-Bosch process.Nitrite is an important intermediate product in the reduction of nitrate to ammonia.Therefore,the mechanism of converting nitrite into ammonia warrants further investigation.Molecular cobalt catalysts are regarded as promising for nitrite reduction reactions(NO_(2)^(−)RR).However,designing and controlling the coordination environment of molecular catalysts is crucial for studying the mechanism of NO_(2)^(−)RR and catalyst design.Herein,we develop a molecular platform of cobalt porphyrin with three coordination microenvironments(Co-N_(3)X_(1),X=N,O,S).Electrochemical experiments demonstrate that cobalt porphyrin with O coordination(CoOTPP)exhibits the lowest onset potential and the highest activity for NO_(2)^(−)RR in ammonia production.Under neutral,nonbuffered conditions over a wide potential range(−1.0 to−1.5 V versus AgCl/Ag),the Faradaic efficiency of nearly 90%for ammonia was achieved and reached 94.5%at−1.4 V versus AgCl/Ag,with an ammonia yield of 6,498μgh^(−1)and a turnover number of 22,869 at−1.5V versus AgCl/Ag.In situ characterization and density functional theory calculations reveal that modulating the coordination environment alters the electron transfer mode of the cobalt active center and the charge redistribution caused by the break of the ligand field.Therefore,this results in enhanced electrochemical activity for NO_(2)^(−)RR in ammonia production.This study provides valuable guidance for designing adjustments to the coordination environment of molecular catalysts to enhance catalytic activity.
基金the National Natural Science Foundation of China(grants 21920102005,21871104,and 22172058)the 111 Project of China(B17020)for supporting this work.
文摘Metal-organic frameworks(MOFs)have shown excellent adsorption and degradation performance towards different kinds of dyes but suffer problems in the desorption process,where adsorbates cannot be completely removed and may cause energy waste or secondary pollution by the repeated washing with eluent,as well as their relatively weak stability in aqueous solutions.Thus,it is very attractive to integrate MOFs with active ingredients to prepare MOF-based composites with dye adsorption and degradation ability.The reported fabrication method of MOF@TiO_(2) usually involves high crystallization temperature or contains acid or base additives,which are unfriendly to MOF structures.Here,we report the design of MOF@TiO_(2) core-shell nanostructures via a surfactant-free amorphous TiO_(2) coating followed by water-assisted crystallization at a low temperature(100℃)below the decomposition temperature of most MOFs.Owing to the mild crystallization conditions,MOF cores are maintained and TiO_(2) shells crystallize to an active anatase phase.The obtained MOF@TiO_(2) core-shell nanostructures showed excellent dye removal efficiency and stability for anionic dyes,which can remove 98% dye after five adsorption and photodegradation cycles due to the synergistic effect of MOF cores and TiO_(2) shells.The design concept and synthetic strategy via the water-assisted crystallization method for labile MOF materials encapsulated in functional TiO_(2) shells may be used to construct other multifunctional MOF core-shell nanostructures,broadening their applications in diverse fields.
基金supported by the National Natural Science Foundation of China(NSFC,21471067 and 51772121)Province Joint Fund(SXGJSF2017-2-4 and SXGJQY2017-1)Program for JLU Science and Technology Innovative Research Team(JLUSTIRT).
文摘The fabrication of photocatalysts to achieve efficient utilization of renewable solar energy has attracted broad interest.Herein,a plasmonic spiky TiO_(2)/Au nanorod(NR)nanohybrid was prepared by in situ nucleation and growth of spiky TiO_(2)in AuNR colloidal solution.The spiky TiO_(2)/AuNR nanohybrids demonstrated enhanced hydrogen evolution activity and photocurrent generation under both visible light and simulated solar light irradiation as compared to bare spiky TiO_(2)nanoparticles and commercial TiO_(2).Specifically,the spiky nanohybrids displayed a high H2 production rate of 1.81 mmol g^(−1)h^(−1)under simulated solar light irradiation,which is 1.7 times higher than that of TiO_(2)/Au nanosphere nanohybrids,and remain stable for three cycles.The improved photocatalytic H2 evolution demonstrated by the nanohybrids can be ascribed to the coupling effect of the AuNRs and the unique spiky structure.Furthermore,the charge transfer process during H2 evolution was investigated by photocurrent and electrochemical impendence spectroscopy(EIS)measurements.A fast and stable photocurrent was observed for the spiky TiO_(2)/AuNR nanohybrid photoelectrode under both visible light and simulated solar light irradiation,while the EIS plots indicate a rapid charge transfer within the nanohybrids.Such a nanohybrid with a bioinspired structure will afford new insights for the fabrication of novel photocatalysts.
基金supported by the National Natural Science Foundation of China(NSFC,21471067,51402121,and 51375204)Jilin Provincial Science&Technology Department(20140520163JH and 20140101056JC)Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry.
文摘A supercapacitor electrode has been fabricated from macroscopic porous MnO2 aerogels,and has demonstrated an enhanced specific capacitance,a high rate capability and excellent cycling durability.The improvement of supercapacitive performance can be attributed to the macro interconnected channels in the aerogel structure,which can not only facilitate mass transfer and reduce dead volume,but also provide an additional benefit of relieving stress.
基金National Key Research and Development Program of China(2022YFC2105800)National Natural Science Foundation of China(22301099 and 22279041)+2 种基金the 111 Project(B17020)the Jilin Province Science and Technology Development Program(20250102085JC)the Australian Research Council(ARC)through the Discovery Project programs(FT230100192)。
文摘Photocatalytic hydrogen evolution(PHE)is one of the most promising methods for clean energy production.However,current photocatalysts are still challenged by limited light absorption and rapid recombination of photogenerated carriers.Constructing defects can effectively broaden light absorption and promote charge separation and transfer.The interface between heterogeneous catalysts is prone to generating multi-component active centers to facilitate the activation of reactants for enhanced catalytic activity.In this report,the combination of defective TiO_(2)and ZnIn_(2)S_(4)of sulfur-rich vacancies(TiO_(2)@ZIS)was developed,which achieved an optimized PHE rate of 9.63 mmol g^(-1)h^(-1).After loading 1.0 wt%Pt cocatalyst,TiO_(2)@ZIS exhibits the apparently-raised PHE rate of 83.41 mmol g^(-1)h^(-1)in the presence of triethanolamine(TEOA)as the sacrificial agent.Theoretical calculation and experimental results reveal that the remarkable hydrogen(H_(2))evolution performance is contributed by the unique Z-scheme charge transfer pathway,which reduces energy loss during charge transfer and facilitates the kinetics of surface H_(2)evolution.This report provides valuable insights into designing and engineering defective materials for solar-driven energy conversion.
