Metal–organic frameworks(MOFs)and layered double hydroxides(LDHs)have been considered to be one of the most promising and worthy hot spot materials to develop advanced catalysts for effi cient hydrogen evolution due ...Metal–organic frameworks(MOFs)and layered double hydroxides(LDHs)have been considered to be one of the most promising and worthy hot spot materials to develop advanced catalysts for effi cient hydrogen evolution due to their prominent characteristics,including unique structures,environmentally friendly nature,high redox activities,and homogeneously eff ective utilization of transition metal atoms.In this work,the delicate S-scheme heterojunction photocatalyst,CoAl LDH@Ni-MOF-74,was rationally designed and successfully constructed by coupling Ni-MOF-74 with CoAl LDH based on their peculiar structure,excellent electronic properties,and opposite surface potential for enhancing hydrogen generation activity under visible light irradiation.The CoAl LDH nanolayers evenly and dispersedly load on the surface of Ni-MOF-74.The CoAl LDH@Ni-MOF-74 exhibited higher photocatalytic hydrogen evolution activity compared with Ni-MOF-74 and CoAl LDH alone,mainly because the formation of the CoAl LDH@Ni-MOF-74 S-scheme heterojunction accelerated the recombination of several electrons(from conduction band(CB)of Ni-MOF-74)and holes(from valence band(VB)of CoAl LDH)and prevented the recombination of other electrons(from CB of CoAl LDH)and holes(from VB of Ni-MOF-74).展开更多
As an ideal secondary energy source,hydrogen has the title of clean energy and the product of its complete combustion is only water,which is not polluting to the environment.Photocatalytic hydrogen production technolo...As an ideal secondary energy source,hydrogen has the title of clean energy and the product of its complete combustion is only water,which is not polluting to the environment.Photocatalytic hydrogen production technology is an environmentally friendly,safe,and low-cost strategy that requires only an inexhaustible amount of solar energy and water as feedstock.This paper provides a detailed and detailed review of S-scheme heterojunction photocatalysts for photocatalytic hydrogen production,mainly including TiO_(2)-based,Perovskite-based,CdS-based,Graphitic phase carbon nitride-based,COF-based graphdiyne-based,ZnO-based,and ZnIn_(2)S_(4)-based S-scheme heterojunction photocatalysts.The classification of S-scheme heterojunctions is summarized.What’s more,various characterizations for direct verification of the charge migration mechanism of S-scheme heterojunctions are outlined.Based on the present study,the future potential challenges and future research trends for S-scheme heterojunctions in photocatalytic hydrogen evolution technology are pointed out,which provides feasible strategies for the development and design of S-scheme heterojunction photocatalysts in the field of photocatalytic hydrogen evolution.展开更多
A novel composite photocatalyst for photocatalytic decomposition of water for hydrogen evolution was successfully synthesized by in-situ growth of nitrogen and sulfur co-doped coal-based carbon quantum dots(NSCQDs)nan...A novel composite photocatalyst for photocatalytic decomposition of water for hydrogen evolution was successfully synthesized by in-situ growth of nitrogen and sulfur co-doped coal-based carbon quantum dots(NSCQDs)nanoparticles on the surface of sheet cobalt-based metal-organic framework(Co-MOF)and graphitic carbon nitride(g-C_(3)N_(4),CN).The structure and properties of the obtained catalysts were systematically analyzed.NSCQDs effectively broaden the absorption of Co-MOF and CN in the visible region.The new composite photocatalyst has high hydrogen production activity and the hydrogen production rate reaches 6254μmol/(g·h)at pH=9.At the same time,NSCQDs synergy Co-MOF/CN composites have good stability.After four cycles of hydrogen production,the performance remains relatively stable.The tran sient photocurrent response and Nyquist plot experimental results further demonstrate the improvement of carrier separation efficiency in composite catalysts.The semiconductor type(n-type semico nductor)of the single-phase catalyst was determined by the Mott-Schottky test,and the band structure was analyzed.The conductive and valence bands of CN are-0.99 and 1.72 eV,respectively,and the conduction and valence bands of Co-MOF are-1.85 and 1.33 eV,respectively.Th e mechanism of the photocatalytic reaction can be inferred,that is,Z-type heterojunction is formed between CN an d Co-MOF,and NSCQDs was used as cocatalyst.展开更多
The photocatalytic performance can be significantly improved by constructing suitable heterojunction photocatalysts.It is well known that graphdiyne possesses a unique conjugated carbon network nanostructure,which giv...The photocatalytic performance can be significantly improved by constructing suitable heterojunction photocatalysts.It is well known that graphdiyne possesses a unique conjugated carbon network nanostructure,which gives it ample active sites on its surface and facilitates the reduction of protons.In this study,a unique new double S-scheme heterojunction photocatalyst was constructed by simple self-assembly of GDY prepared via organic synthesis methods and ZnAl-LDH.According to the study,an internal electric field controlling the transfer direction of the electron hole is formed between the interface of CuI-GDY and ZnAl-LDH,which broadens the light absorption range of the catalyst and improves the redox ability of the photocatalytic system.CuI-GDY and ZnAl-LDH are tightly bound together,which helps to separate the photogenerated carriers while preserving the strong reduction electrons in the GDY conduction band and the strong oxidation holes in the ZnAl-LDH valence band so that they can fully participate in the redox reaction.The charge-transfer paths on the S-scheme heterojunction interface were analyzed by in situ irradiation XPS.This work provides an effective strategy for the construction of double S-scheme heterojunction photocatalysts.展开更多
In this study,the hydrogen evolution performance of CdS nanorods is improved using ZnCo_(2)O_(4).ZnCo_(2)O_(4)nanospheres are synthesized using the hydrothermal and calcination methods,and CdS nanorods are synthesized...In this study,the hydrogen evolution performance of CdS nanorods is improved using ZnCo_(2)O_(4).ZnCo_(2)O_(4)nanospheres are synthesized using the hydrothermal and calcination methods,and CdS nanorods are synthesized using the solvothermal method.From the perspective of morphology,numerous CdS nanorods are anchored on the ZnCo_(2)O_(4)microspheres.According to the experimental results of photocatalytic hydrogen evolution,the final hydrogen evolution capacity of 7417.5μmol·g^(-1)·h^(-1)is slightly more than two times that of the single CdS,which proves the feasibility of our study.Through various characterization methods,it is proved that the composite sample has suitable optoelectronic properties.In addition,ZnCo_(2)O_(4)itself exhibits good conductivity and low impedance,which shortens the charge-transfer path.Overall,the introduction of ZnCo_(2)O_(4)expands the adsorption range of light and improves the performance of photocatalytic hydrogen evolution.This design can provide reference for developing high-efficiency photocatalysts.展开更多
Interface engineering of photocatalysts is an effective way to enhance their photocatalytic activity.In this work,the MOF-on-MOF strategy was used to construct the ZIF-9(Co)/Cu_(3)BTC_(2) photocatalyst in situ.Moreove...Interface engineering of photocatalysts is an effective way to enhance their photocatalytic activity.In this work,the MOF-on-MOF strategy was used to construct the ZIF-9(Co)/Cu_(3)BTC_(2) photocatalyst in situ.Moreover,graph-diyne,possessing an inherent capability to facilitate rapid electron transfer at the interface,has been introduced into the ZIF-9(Co)/Cu_(3)BTC_(2) interface to regulate the interfacial carrier migration.The photogenerated carrier transfer capability has been significantly enhanced by the interfacial synergy,while retaining the original active sites and high specific surface area.The exceptional efficiency performance of the composite catalyst under identical conditions could be attributed to the following two key factors:(i)The interfacial S-scheme hetero-junction in ZIF-9(Co)/Cu_(3)BTC_(2) provides the composite catalyst with strong reduction activity,facilitating the involvement of additional electrons in the reduction reaction through bended bands and an internal electric field.(ii)Carrier dynamics analysis shows that graphdiyne,as an electron transport layer,accelerates the charge migration rate at the S-scheme heterojunction interface through the electron relay effect.The incorporation of graphdiyne greatly improves the catalytic activity of MOFs and also demonstrates the great potential of graph-diyne in photocatalysis.This work provides a feasible idea for the interface engineering design of graphdiyne in photocatalysts.展开更多
The Ni-Cu bimetallic nanoparticles were successfully anchorred on the surface of g-C3N4 nanosheets by a simple heat treatment process which was applied to the photocatalytic hydrogen evolution reaction.Insitu introduc...The Ni-Cu bimetallic nanoparticles were successfully anchorred on the surface of g-C3N4 nanosheets by a simple heat treatment process which was applied to the photocatalytic hydrogen evolution reaction.Insitu introduction of Ni-Cu could significantly improve the photocatalytic hydrogen evolution performance compared with pure g-C3N4 in the system sensitized by eosin Y under a visible irradiation condition.The hydrogen production activity of the composite reached 104.4μmol(2088.28μmol g^-1 h^-1)after using the Ni Cu double promoter strategy,which was 24.3 times higher than g-C3N4.The excellent electrical conductivity of the bimetallic Ni-Cu and the close interfacial contact between Ni Cu and g-C3N4 played an important role for increasing the charge transfer rate.They were also the reasons of more efficient charge separation,which ultimately led to a significant promotion on the photocatalytic hydrogen production reaction.Ni-Cu/g-C3N4 coupling with a close Schottky interface between metal and semiconductor which enhanced H2-evolution performance and TEOA oxidation kinetics.This work provided a new way to load Ni Cu bimetallic nanoparticles in situ onto g-C3N4 and a reference on relative semiconductor materials.展开更多
The charge separation efficiency is one of the main factors affecting the solar photocatalytic decomposition of water to produce hydrogen.Constructing a unique heterojunction can accelerate the separation and transfer...The charge separation efficiency is one of the main factors affecting the solar photocatalytic decomposition of water to produce hydrogen.Constructing a unique heterojunction can accelerate the separation and transfer of photo-generated charges,and effectively improve the photocatalytic efficiency,which is considered a potential strategy.Accordingly,the 2%Cu_(2)S/CZS step-scheme(S-scheme)heterojunction based on morphology and electronic structure was successfully prepared via simple hydrothermal method.Compared with the monomer Cu_(2)S and Cd Zn S,the hydrogen evolution rate of 2%Cu_(2)S/CZS samples is significantly increased.In particular,the 2%Cu_(2)S/CZS not only shows high hydrogen evolution rate of 5904μmol g^(-1)h^(-1)(3.19 times than original Cd Zn S),but also presents preferable cyclic endurance.According to the characterization,we believe that the introduction of Cu_(2)S has the following three advantages:(i)The snowflake structure of Cu_(2)S reduces the agglomeration of granular Cd Zn S.(ii)The Cu_(2)S with narrow band gap broadens the light response range of the composite catalyst.(iii)The Cu_(2)S was introduced into Cd Zn S to form S-scheme heterojunction,which accelerated the separation and transfer of photo-generated charge.This work broadens the idea of designing efficient photocatalyst of hydrogen evolution.展开更多
Reasonable design of heterojunction can greatly improve the photocatalytic hydrogen evolution activity of materials.Herein,p-n heterojunction of 2D/3D structure is constructed by the nanosheet of CoAl-LDH and rock-lik...Reasonable design of heterojunction can greatly improve the photocatalytic hydrogen evolution activity of materials.Herein,p-n heterojunction of 2D/3D structure is constructed by the nanosheet of CoAl-LDH and rock-like CuI.The introduction of CuI can make CoAl-LDH disperse better,which brings more reaction sites for the hydrogen evolution reaction.Meanwhile,the 2D/3D structure is conducive to the construction of p-n heterojunction between the CoAl-LDH and CuI.The optical and electrochemical properties of the material indicate that the separation and transference of photon-generated carriers are promoted by the p-n heterojunction.The activity of composite catalyst(CI-10)reaches a maximum of 3.59 mmol g^(−1) h^(−1) which is 28.5 times higher than that of CuI.Furthermore,the influence of the amount of CuI and pH value on the hydrogen evolution reaction is explored.Based on the band structures of CoAl-LDH and CuI,the mechanism of photocatalytic reaction of CI-10 is proposed.The p-n heterojunction constructed with the CuI as hole receptor provides a new way to enhance the activity of photocatalytic H_(2) evolution.展开更多
Photocatalytic hydrogen evolution can convert intermittent and dispersive solar energy into hydrogen with high energy density,which is expected to fundamentally solve the problems of environmental pollution and energy...Photocatalytic hydrogen evolution can convert intermittent and dispersive solar energy into hydrogen with high energy density,which is expected to fundamentally solve the problems of environmental pollution and energy shortages.In this experiment,the performance of the catalyst is modified by introducing cocatalyst and morphology control.Ni(OH)2 nanoflowers are used as substrates to derive nanoplate stack Ni_(2)P by high-temperature phosphating method,and a great many of CeO_(2) nanoparticles are anchored in the Ni_(2)P.This unique 3D/0D combination effectively inhibits the agglomeration of CeO_(2) nanoparticles and shortens the electron transfer path.Secondly,the introduction of metal-like performance of Ni_(2)P broadens the light absorption range of the catalyst and reduces the overpotential of the catalyst,which is a key factor in enhancing the catalytic activity.The design ideas of this experiment have reference significance for the design of efficient and environmentally friendly photocatalysts.展开更多
Solar energy is the most important clean and renewable energy in the world.However,the unpredictability,seasonal variation day and night,uneven distribution and low energy density limit its practical application.Photo...Solar energy is the most important clean and renewable energy in the world.However,the unpredictability,seasonal variation day and night,uneven distribution and low energy density limit its practical application.Photocatalysis technology has a very broad application prospect in solving energy and environmental problems.展开更多
基金supported by the National Natural Science Foundation of China(21433007,21603274,41663012)the Ningxia Low-Grade Resource High Value Utilization and Environmental Chemical Integration Technology Innovation Team Project,North Minzu University~~
基金supported by the National Natural Science Foundation of China(21862002,41663012)the Innovation Team Project of North Minzu University(YCX18082)the Scientific Research Project of North Minzu University(2016 HG-KY 06)~~
基金This work was financially supported by the Natural Science Foundation of the Ningxia Hui Autonomous Region(No.2020AAC02026).
文摘Metal–organic frameworks(MOFs)and layered double hydroxides(LDHs)have been considered to be one of the most promising and worthy hot spot materials to develop advanced catalysts for effi cient hydrogen evolution due to their prominent characteristics,including unique structures,environmentally friendly nature,high redox activities,and homogeneously eff ective utilization of transition metal atoms.In this work,the delicate S-scheme heterojunction photocatalyst,CoAl LDH@Ni-MOF-74,was rationally designed and successfully constructed by coupling Ni-MOF-74 with CoAl LDH based on their peculiar structure,excellent electronic properties,and opposite surface potential for enhancing hydrogen generation activity under visible light irradiation.The CoAl LDH nanolayers evenly and dispersedly load on the surface of Ni-MOF-74.The CoAl LDH@Ni-MOF-74 exhibited higher photocatalytic hydrogen evolution activity compared with Ni-MOF-74 and CoAl LDH alone,mainly because the formation of the CoAl LDH@Ni-MOF-74 S-scheme heterojunction accelerated the recombination of several electrons(from conduction band(CB)of Ni-MOF-74)and holes(from valence band(VB)of CoAl LDH)and prevented the recombination of other electrons(from CB of CoAl LDH)and holes(from VB of Ni-MOF-74).
基金supported by the Chinese National Natural Science Foundation(No.22062001).
文摘As an ideal secondary energy source,hydrogen has the title of clean energy and the product of its complete combustion is only water,which is not polluting to the environment.Photocatalytic hydrogen production technology is an environmentally friendly,safe,and low-cost strategy that requires only an inexhaustible amount of solar energy and water as feedstock.This paper provides a detailed and detailed review of S-scheme heterojunction photocatalysts for photocatalytic hydrogen production,mainly including TiO_(2)-based,Perovskite-based,CdS-based,Graphitic phase carbon nitride-based,COF-based graphdiyne-based,ZnO-based,and ZnIn_(2)S_(4)-based S-scheme heterojunction photocatalysts.The classification of S-scheme heterojunctions is summarized.What’s more,various characterizations for direct verification of the charge migration mechanism of S-scheme heterojunctions are outlined.Based on the present study,the future potential challenges and future research trends for S-scheme heterojunctions in photocatalytic hydrogen evolution technology are pointed out,which provides feasible strategies for the development and design of S-scheme heterojunction photocatalysts in the field of photocatalytic hydrogen evolution.
基金Project supported by the Ningxia Natural Science Foundation of China(2023AAC03285)National Natural Science Foundation of China(21666001)+1 种基金Innovative Team for Transforming Waste Cooking Oil into Clean Energy and High Value-added Chemicals,ChinaNingxia Low-grade Resource High Value Utilization and Environmental Chemical Integration Technology Innovation Team Project,China。
文摘A novel composite photocatalyst for photocatalytic decomposition of water for hydrogen evolution was successfully synthesized by in-situ growth of nitrogen and sulfur co-doped coal-based carbon quantum dots(NSCQDs)nanoparticles on the surface of sheet cobalt-based metal-organic framework(Co-MOF)and graphitic carbon nitride(g-C_(3)N_(4),CN).The structure and properties of the obtained catalysts were systematically analyzed.NSCQDs effectively broaden the absorption of Co-MOF and CN in the visible region.The new composite photocatalyst has high hydrogen production activity and the hydrogen production rate reaches 6254μmol/(g·h)at pH=9.At the same time,NSCQDs synergy Co-MOF/CN composites have good stability.After four cycles of hydrogen production,the performance remains relatively stable.The tran sient photocurrent response and Nyquist plot experimental results further demonstrate the improvement of carrier separation efficiency in composite catalysts.The semiconductor type(n-type semico nductor)of the single-phase catalyst was determined by the Mott-Schottky test,and the band structure was analyzed.The conductive and valence bands of CN are-0.99 and 1.72 eV,respectively,and the conduction and valence bands of Co-MOF are-1.85 and 1.33 eV,respectively.Th e mechanism of the photocatalytic reaction can be inferred,that is,Z-type heterojunction is formed between CN an d Co-MOF,and NSCQDs was used as cocatalyst.
基金financially supported by the Innovative team for transforming waste cooking oil into clean energy and high valueadded chemicals,China and Ningxia lowgrade resource high value utilization and environmental chemical integration technology innovation team project.
文摘The photocatalytic performance can be significantly improved by constructing suitable heterojunction photocatalysts.It is well known that graphdiyne possesses a unique conjugated carbon network nanostructure,which gives it ample active sites on its surface and facilitates the reduction of protons.In this study,a unique new double S-scheme heterojunction photocatalyst was constructed by simple self-assembly of GDY prepared via organic synthesis methods and ZnAl-LDH.According to the study,an internal electric field controlling the transfer direction of the electron hole is formed between the interface of CuI-GDY and ZnAl-LDH,which broadens the light absorption range of the catalyst and improves the redox ability of the photocatalytic system.CuI-GDY and ZnAl-LDH are tightly bound together,which helps to separate the photogenerated carriers while preserving the strong reduction electrons in the GDY conduction band and the strong oxidation holes in the ZnAl-LDH valence band so that they can fully participate in the redox reaction.The charge-transfer paths on the S-scheme heterojunction interface were analyzed by in situ irradiation XPS.This work provides an effective strategy for the construction of double S-scheme heterojunction photocatalysts.
基金supported by the National Natural Science Foundation of China(Grant No.22062001)the graduate innovation project of North Minzu University(Grant No.YCX22166).
文摘In this study,the hydrogen evolution performance of CdS nanorods is improved using ZnCo_(2)O_(4).ZnCo_(2)O_(4)nanospheres are synthesized using the hydrothermal and calcination methods,and CdS nanorods are synthesized using the solvothermal method.From the perspective of morphology,numerous CdS nanorods are anchored on the ZnCo_(2)O_(4)microspheres.According to the experimental results of photocatalytic hydrogen evolution,the final hydrogen evolution capacity of 7417.5μmol·g^(-1)·h^(-1)is slightly more than two times that of the single CdS,which proves the feasibility of our study.Through various characterization methods,it is proved that the composite sample has suitable optoelectronic properties.In addition,ZnCo_(2)O_(4)itself exhibits good conductivity and low impedance,which shortens the charge-transfer path.Overall,the introduction of ZnCo_(2)O_(4)expands the adsorption range of light and improves the performance of photocatalytic hydrogen evolution.This design can provide reference for developing high-efficiency photocatalysts.
基金supprted by the“Fundamental Research Funds for the Central Universities”,North Minzu University(2023XYZHG01)Ningxia low-grade resource high value utilization and environmental chemical integration technology innovation team projectInnovative team for transforming waste cooking oil into clean energy and high value-added chemicals,China
文摘Interface engineering of photocatalysts is an effective way to enhance their photocatalytic activity.In this work,the MOF-on-MOF strategy was used to construct the ZIF-9(Co)/Cu_(3)BTC_(2) photocatalyst in situ.Moreover,graph-diyne,possessing an inherent capability to facilitate rapid electron transfer at the interface,has been introduced into the ZIF-9(Co)/Cu_(3)BTC_(2) interface to regulate the interfacial carrier migration.The photogenerated carrier transfer capability has been significantly enhanced by the interfacial synergy,while retaining the original active sites and high specific surface area.The exceptional efficiency performance of the composite catalyst under identical conditions could be attributed to the following two key factors:(i)The interfacial S-scheme hetero-junction in ZIF-9(Co)/Cu_(3)BTC_(2) provides the composite catalyst with strong reduction activity,facilitating the involvement of additional electrons in the reduction reaction through bended bands and an internal electric field.(ii)Carrier dynamics analysis shows that graphdiyne,as an electron transport layer,accelerates the charge migration rate at the S-scheme heterojunction interface through the electron relay effect.The incorporation of graphdiyne greatly improves the catalytic activity of MOFs and also demonstrates the great potential of graph-diyne in photocatalysis.This work provides a feasible idea for the interface engineering design of graphdiyne in photocatalysts.
基金financially supported by the Open Project of State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering,Ningxia University(No.2019-KF-36)the Chinese National Natural Science Foundation(Nos.21862002 and 41663012)+2 种基金the new technology and system for clean energy catalytic productionMajor scientific project of North Minzu University(No.ZDZX201803)The Ningxia low-grade resource high value utilization and environmental chemical integration technology innovation team project,North Minzu University。
文摘The Ni-Cu bimetallic nanoparticles were successfully anchorred on the surface of g-C3N4 nanosheets by a simple heat treatment process which was applied to the photocatalytic hydrogen evolution reaction.Insitu introduction of Ni-Cu could significantly improve the photocatalytic hydrogen evolution performance compared with pure g-C3N4 in the system sensitized by eosin Y under a visible irradiation condition.The hydrogen production activity of the composite reached 104.4μmol(2088.28μmol g^-1 h^-1)after using the Ni Cu double promoter strategy,which was 24.3 times higher than g-C3N4.The excellent electrical conductivity of the bimetallic Ni-Cu and the close interfacial contact between Ni Cu and g-C3N4 played an important role for increasing the charge transfer rate.They were also the reasons of more efficient charge separation,which ultimately led to a significant promotion on the photocatalytic hydrogen production reaction.Ni-Cu/g-C3N4 coupling with a close Schottky interface between metal and semiconductor which enhanced H2-evolution performance and TEOA oxidation kinetics.This work provided a new way to load Ni Cu bimetallic nanoparticles in situ onto g-C3N4 and a reference on relative semiconductor materials.
基金the Chinese National Natural Science Foundation(No.22062001)the Natural Science Foundation of the Ningxia Hui Autonomous Region(Nos.2020AAC03209 and 2020AAC02026)+2 种基金The Ningxia low-grade resource high value utilization and environmental chemical integration technology innovation team project,North Minzu UniversityThe Innovation team of clean energy and green chemical Engineering,State Ethnic Affairs Commissionthe Fifth Batch of Ningxia Young Scientific and Technological Talents Promotion Project for financial support。
文摘The charge separation efficiency is one of the main factors affecting the solar photocatalytic decomposition of water to produce hydrogen.Constructing a unique heterojunction can accelerate the separation and transfer of photo-generated charges,and effectively improve the photocatalytic efficiency,which is considered a potential strategy.Accordingly,the 2%Cu_(2)S/CZS step-scheme(S-scheme)heterojunction based on morphology and electronic structure was successfully prepared via simple hydrothermal method.Compared with the monomer Cu_(2)S and Cd Zn S,the hydrogen evolution rate of 2%Cu_(2)S/CZS samples is significantly increased.In particular,the 2%Cu_(2)S/CZS not only shows high hydrogen evolution rate of 5904μmol g^(-1)h^(-1)(3.19 times than original Cd Zn S),but also presents preferable cyclic endurance.According to the characterization,we believe that the introduction of Cu_(2)S has the following three advantages:(i)The snowflake structure of Cu_(2)S reduces the agglomeration of granular Cd Zn S.(ii)The Cu_(2)S with narrow band gap broadens the light response range of the composite catalyst.(iii)The Cu_(2)S was introduced into Cd Zn S to form S-scheme heterojunction,which accelerated the separation and transfer of photo-generated charge.This work broadens the idea of designing efficient photocatalyst of hydrogen evolution.
基金financially supported by the National Natural Science Foundation of China(22062001)。
文摘Reasonable design of heterojunction can greatly improve the photocatalytic hydrogen evolution activity of materials.Herein,p-n heterojunction of 2D/3D structure is constructed by the nanosheet of CoAl-LDH and rock-like CuI.The introduction of CuI can make CoAl-LDH disperse better,which brings more reaction sites for the hydrogen evolution reaction.Meanwhile,the 2D/3D structure is conducive to the construction of p-n heterojunction between the CoAl-LDH and CuI.The optical and electrochemical properties of the material indicate that the separation and transference of photon-generated carriers are promoted by the p-n heterojunction.The activity of composite catalyst(CI-10)reaches a maximum of 3.59 mmol g^(−1) h^(−1) which is 28.5 times higher than that of CuI.Furthermore,the influence of the amount of CuI and pH value on the hydrogen evolution reaction is explored.Based on the band structures of CoAl-LDH and CuI,the mechanism of photocatalytic reaction of CI-10 is proposed.The p-n heterojunction constructed with the CuI as hole receptor provides a new way to enhance the activity of photocatalytic H_(2) evolution.
基金This work was financially supported by the Chinese National Natural Science Foundation(201862002).
文摘Photocatalytic hydrogen evolution can convert intermittent and dispersive solar energy into hydrogen with high energy density,which is expected to fundamentally solve the problems of environmental pollution and energy shortages.In this experiment,the performance of the catalyst is modified by introducing cocatalyst and morphology control.Ni(OH)2 nanoflowers are used as substrates to derive nanoplate stack Ni_(2)P by high-temperature phosphating method,and a great many of CeO_(2) nanoparticles are anchored in the Ni_(2)P.This unique 3D/0D combination effectively inhibits the agglomeration of CeO_(2) nanoparticles and shortens the electron transfer path.Secondly,the introduction of metal-like performance of Ni_(2)P broadens the light absorption range of the catalyst and reduces the overpotential of the catalyst,which is a key factor in enhancing the catalytic activity.The design ideas of this experiment have reference significance for the design of efficient and environmentally friendly photocatalysts.
文摘Solar energy is the most important clean and renewable energy in the world.However,the unpredictability,seasonal variation day and night,uneven distribution and low energy density limit its practical application.Photocatalysis technology has a very broad application prospect in solving energy and environmental problems.
