The metal promoted In_(2)O_(3) catalysts for CO_(2) hydrogenation to methanol have attracted wide attention because of their high activity with high methanol selectivity.However,there was still no experimental confirm...The metal promoted In_(2)O_(3) catalysts for CO_(2) hydrogenation to methanol have attracted wide attention because of their high activity with high methanol selectivity.However,there was still no experimental confirmation if copper could be a good promoter for In_(2)O_(3).Herein,the Cu promoted In_(2)O_(3) catalyst was prepared using a deposition-precipitation method.Such prepared Cu/In_(2)O_(3) catalyst shows significantly higher CO_(2) conversion and space time yield(STY)of methanol,compared to the un-promoted In_(2)O_(3) catalyst.The loading of Cu facilitates the activation of both H_(2) and CO_(2) with the interface between the Cu cluster and defective In_(2)O_(3) as the active site.The Cu/In_(2)O_(3) catalyst takes the CO hydrogenation pathway for methanol synthesis from CO_(2) hydrogenation.It exhibits a unique size effect on the CO adsorption.At temperatures below 250℃,CO adsorption on Cu/In_(2)O_(3) is stronger than that on In_(2)O_(3),causing higher methanol selectivity.With increasing temperatu res,the Cu catalyst aggregates,which leads to the formation of weak CO adsorption site and causes a decrease in the methanol selectivity.Compared with other metal promoted In_(2)O_(3) catalysts,it can be concluded that the catalyst with stronger CO adsorption possesses higher methanol selectivity.展开更多
系统研究了Ag Sn In Ni合金内氧化法制备Ag-Sn O_(2)-In_(2)O_(3)-Ni O电接触材料的微观组织演变机理及氧化物颗粒分布的调控。结果表明,退火工艺决定了Ag Sn In Ni的缺陷状态,随退火温度的升高,合金中缺陷密度降低,内氧化速度减慢。内...系统研究了Ag Sn In Ni合金内氧化法制备Ag-Sn O_(2)-In_(2)O_(3)-Ni O电接触材料的微观组织演变机理及氧化物颗粒分布的调控。结果表明,退火工艺决定了Ag Sn In Ni的缺陷状态,随退火温度的升高,合金中缺陷密度降低,内氧化速度减慢。内氧化过程中银合金同时发生回复与再结晶,但内氧化形成的Sn O_(2)和In_(2)O_(3)颗粒可钉扎位错、亚晶界等缺陷,抑制再结晶的发生。Ag-Sn O_(2)-In_(2)O_(3)-Ni O合金微观组织的差异是O原子沿着缺陷向样品内部扩散与Ag合金基体发生再结晶的相互竞争的结果,这导致了芯部组织为氧化物密度较低的颗粒状分布,而外侧组织为氧化物颗粒沿着缺陷墙呈现束装聚集分布。退火工艺为550℃/2 h、氧化工艺为700℃/0.3 MPa×26 h时,可获得氧化物尺寸和分布一致性高的Ag-Sn O_(2)-In_(2)O_(3)-Ni O材料。展开更多
利用可再生的电能将CO_(2)还原为高附加值的化学品和燃料,对于缓解温室效应并实现碳中和具有重要的意义。开发了一种简单有效的方法制备非金属P元素掺杂的In_(2)O_(3)纳米颗粒,并将其用于电催化CO_(2)还原制甲酸盐。在H型电解池中,在-1....利用可再生的电能将CO_(2)还原为高附加值的化学品和燃料,对于缓解温室效应并实现碳中和具有重要的意义。开发了一种简单有效的方法制备非金属P元素掺杂的In_(2)O_(3)纳米颗粒,并将其用于电催化CO_(2)还原制甲酸盐。在H型电解池中,在-1.45 V vs.RHE电位下,P掺杂的In_(2)O_(3)纳米催化剂的产甲酸法拉第效率达到88.2%,同时具有优异的稳定性。进一步的实验分析和理论研究表明,掺杂在In_(2)O_(3)晶格中的P元素显著促进了CO_(2)分子的吸附和活化,降低了形成*HCOO中间体的吉布斯自由能,同时加强了对*HCOO的吸附作用,最终促进了甲酸盐的合成。阐明了非金属元素P掺杂对提升CO_(2)还原反应性能的分子机制,同时也为其他金属氧化物基的高性能电催化剂的设计提供了一种可行的策略。展开更多
Indium oxide(In_(2)O_(3)),as a promising candidate for CO_(2)hydrogenation to C_(1) products,often suffers from sintering and activity decline,closely related to the undesirable structural evolution under reaction con...Indium oxide(In_(2)O_(3)),as a promising candidate for CO_(2)hydrogenation to C_(1) products,often suffers from sintering and activity decline,closely related to the undesirable structural evolution under reaction conditions.Based on the comprehension of the dynamic evolution,this study presents an efficient strategy to alleviate the agglomeration of In_(2)O_(3)nanoparticles by the surface decoration with highly dispersed silica species(SiO_(x)).Various structural characterizations combined with density functional theory calculations demonstrated that the sintering resulted from the over-reduction,while the enhanced stability originated from the anchoring effect of highly stable In-OSi bonds,which hinders the substantial formation of metallic In(In^(0))and the subsequent agglomeration.0.6Si/In_(2)O_(3)exhibited CO_(2)conversion rate of10.0 mmol g^(-1)h^(-1)at steady state vs.3.5 mmol g^(-1)h^(-1)on In_(2)O_(3)in CO_(2)hydrogenation.Enhanced steady-state activity was also achieved on Pd-modified catalysts.Compared to the traditional Pd/In_(2)O_(3)catalyst,the methanol production rate of Pd catalyst supported on 0.6Si/In_(2)O_(3)was enhanced by 23%,showing the potential of In_(2)O_(3)modified by SiO_(x)in serving as a platform material.This work provides a promising method to design new In_(2)O_(3)-based catalysts with improved activity and stability in CO_(2)hydrogenation.展开更多
The development of an efficient artificial H_(2)O_(2) photosynthesis system is a challenging work using H_(2)O and O_(2) as starting materials.Herein,3D In_(2.77)S_(4) nanoflower precursor was in-situ deposited on K^(...The development of an efficient artificial H_(2)O_(2) photosynthesis system is a challenging work using H_(2)O and O_(2) as starting materials.Herein,3D In_(2.77)S_(4) nanoflower precursor was in-situ deposited on K^(+)-doped g-C_(3)N_(4)(KCN)nanosheets using a solvothermal method,then In_(2.77)S_(4)/KCN(IS/KCN)het-erojunction with an intimate interface was obtained after a calcination process.The investigation shows that the photocatalytic H_(2)O_(2) production rate of 50IS/KCN can reach up to 1.36 mmol g^(-1)h^(-1)without any sacrificial reagents under visible light irradiation,which is 9.2 times and 4.1 times higher than that of KCN and In_(2.77)S_(4)/respectively.The enhanced activity of the above composite can be mainly attributed to the S-scheme charge transfer route between KCN and In_(2.77)S_(4) according to density functional theory calculations,electron paramagnetic resonance and free radical capture tests,leading to an expanded light response range and rapid charge separation at their interface,as well as preserving the active electrons and holes for H_(2)O_(2) production.Besides,the unique 3D nanostructure and surface hydrophobicity of IS/KCN facilitate the diffusion and transportation of O_(2) around the active centers,the energy barriers of O_(2) protonation and H_(2)O_(2) desorption steps are ef-fectively reduced over the composite.In addition,this system also exhibits excellent light harvesting ability and stability.This work provides a potential strategy to explore a sustainable H_(2)O_(2) photo-synthesis pathway through the design of heterojunctions with intimate interfaces and desired reac-tion thermodynamics and kinetics.展开更多
Z-scheme photocatalytic system has been regarded as a popular field of research in photoelectrochemical(PEC)water splitting.Among the many obstacles facing a Z-scheme photocatalytic system,the analysis methods of inte...Z-scheme photocatalytic system has been regarded as a popular field of research in photoelectrochemical(PEC)water splitting.Among the many obstacles facing a Z-scheme photocatalytic system,the analysis methods of interfacial Z-scheme charge transfer still remain a significant challenge.Hence,in this study,CdS/Ti-Fe_(2)O_(3)heterojunction photoanodes are elaborately designed to explore the charge-transfer behavior in PEC water splitting.In this study,photophysical measurements,including the Kelvin probe measurement,surface photovoltage spectroscopy(SPV),and transient photovoltage spectroscopy(TPV),are used to monitor the migration behavior of photogenerated charges at the interface electric field of CdS/Ti-Fe_(2)O_(3)Z-scheme heterojunction photoanodes.The Kelvin probe and SPV measurements demonstrate that CdS/Ti-Fe_(2)O_(3)interfacial driving force favors the rapid transfer of photoexcited electrons to CdS.The double-beam strategy based on TPV indicates that more electrons of Ti-Fe_(2)O_(3)are combined with the holes of CdS owing to the intensive interface electric field.The results of these measurements successfully prove the Z-scheme migration mechanism of CdS/Ti-Fe_(2)O_(3)photoanodes.Benefiting from the desirable charge transfer at the interface electric field,CdS/Ti-Fe_(2)O_(3)photoanodes exhibit superior photocatalytic oxygen evolution reaction performance compared with that of pure Ti-Fe_(2)O_(3).The photocurrent density of the 25CdS/Ti-Fe_(2)O_(3)photoanode reaches 1.94 mA/cm^(2) at 1.23 V versus reversible hydrogen electrode without excess cocatalyst,and it is two times higher than that of pure Ti-Fe_(2)O_(3)photoanode.Therefore,an outstanding strategy is provided in this study to prove the Z-scheme charge-transfer mechanism of photocatalytic systems in PEC water splitting.展开更多
Photocatalytic water splitting for hydrogen production(H_(2))is one of the main potential applications of photocatalytic technology,which can use solar energy as the energy required for chemical reactions to alleviate...Photocatalytic water splitting for hydrogen production(H_(2))is one of the main potential applications of photocatalytic technology,which can use solar energy as the energy required for chemical reactions to alleviate the energy crisis.In this work,zero-dimensional/two-dimensional(0D/2D)contact surface CdS/α-Fe_(2)O_(3)(CF)heterojunction photocatalyst was synthesized via a simple solvothermal method.Photocatalytic hydrogen production experiments revealed that the CF-15 sample shows the optimal photocatalytic H_(2)rate(1806μmol·h^(-1)·g^(-1))and apparent quantum efficiency(AQE=13.7%atλ=420 nm).The enhancement of photocatalytic performance is mainly attributed to the contact of 0D/2D interface and the synergistic effect of Z-scheme electron transfer mechanism.This work provides an effective way for modified composite semiconductor photocatalyst by constructing special interface heterojunction to achieve highly efficiently catalysis.展开更多
基金supported by the National Natural Science Foundation of China(22138009)the Fundamental Research Funds for the Central Universities of China。
文摘The metal promoted In_(2)O_(3) catalysts for CO_(2) hydrogenation to methanol have attracted wide attention because of their high activity with high methanol selectivity.However,there was still no experimental confirmation if copper could be a good promoter for In_(2)O_(3).Herein,the Cu promoted In_(2)O_(3) catalyst was prepared using a deposition-precipitation method.Such prepared Cu/In_(2)O_(3) catalyst shows significantly higher CO_(2) conversion and space time yield(STY)of methanol,compared to the un-promoted In_(2)O_(3) catalyst.The loading of Cu facilitates the activation of both H_(2) and CO_(2) with the interface between the Cu cluster and defective In_(2)O_(3) as the active site.The Cu/In_(2)O_(3) catalyst takes the CO hydrogenation pathway for methanol synthesis from CO_(2) hydrogenation.It exhibits a unique size effect on the CO adsorption.At temperatures below 250℃,CO adsorption on Cu/In_(2)O_(3) is stronger than that on In_(2)O_(3),causing higher methanol selectivity.With increasing temperatu res,the Cu catalyst aggregates,which leads to the formation of weak CO adsorption site and causes a decrease in the methanol selectivity.Compared with other metal promoted In_(2)O_(3) catalysts,it can be concluded that the catalyst with stronger CO adsorption possesses higher methanol selectivity.
文摘系统研究了Ag Sn In Ni合金内氧化法制备Ag-Sn O_(2)-In_(2)O_(3)-Ni O电接触材料的微观组织演变机理及氧化物颗粒分布的调控。结果表明,退火工艺决定了Ag Sn In Ni的缺陷状态,随退火温度的升高,合金中缺陷密度降低,内氧化速度减慢。内氧化过程中银合金同时发生回复与再结晶,但内氧化形成的Sn O_(2)和In_(2)O_(3)颗粒可钉扎位错、亚晶界等缺陷,抑制再结晶的发生。Ag-Sn O_(2)-In_(2)O_(3)-Ni O合金微观组织的差异是O原子沿着缺陷向样品内部扩散与Ag合金基体发生再结晶的相互竞争的结果,这导致了芯部组织为氧化物密度较低的颗粒状分布,而外侧组织为氧化物颗粒沿着缺陷墙呈现束装聚集分布。退火工艺为550℃/2 h、氧化工艺为700℃/0.3 MPa×26 h时,可获得氧化物尺寸和分布一致性高的Ag-Sn O_(2)-In_(2)O_(3)-Ni O材料。
文摘利用可再生的电能将CO_(2)还原为高附加值的化学品和燃料,对于缓解温室效应并实现碳中和具有重要的意义。开发了一种简单有效的方法制备非金属P元素掺杂的In_(2)O_(3)纳米颗粒,并将其用于电催化CO_(2)还原制甲酸盐。在H型电解池中,在-1.45 V vs.RHE电位下,P掺杂的In_(2)O_(3)纳米催化剂的产甲酸法拉第效率达到88.2%,同时具有优异的稳定性。进一步的实验分析和理论研究表明,掺杂在In_(2)O_(3)晶格中的P元素显著促进了CO_(2)分子的吸附和活化,降低了形成*HCOO中间体的吉布斯自由能,同时加强了对*HCOO的吸附作用,最终促进了甲酸盐的合成。阐明了非金属元素P掺杂对提升CO_(2)还原反应性能的分子机制,同时也为其他金属氧化物基的高性能电催化剂的设计提供了一种可行的策略。
基金financially supported by the National Natural Science Foundation of China(22172013)the Special Project for Key Research and Development Program of Xinjiang Autonomous Region(2022B01033-3)+3 种基金the Liaoning Revitalization Talent Program(XLYC2008032 and XLYC2203126)the Fundamental Research Funds for the Central Universities(DUT22LK24,DUT22QN207 and DUT22LAB602)the CUHK Research Startup Fund(No.#4930981)financial support from Catalyst:Seeding funding(CSG-VUW2201)provided by the New Zealand Ministry of Business,Innovation and Employment and administered by the Royal Society Aparangi。
文摘Indium oxide(In_(2)O_(3)),as a promising candidate for CO_(2)hydrogenation to C_(1) products,often suffers from sintering and activity decline,closely related to the undesirable structural evolution under reaction conditions.Based on the comprehension of the dynamic evolution,this study presents an efficient strategy to alleviate the agglomeration of In_(2)O_(3)nanoparticles by the surface decoration with highly dispersed silica species(SiO_(x)).Various structural characterizations combined with density functional theory calculations demonstrated that the sintering resulted from the over-reduction,while the enhanced stability originated from the anchoring effect of highly stable In-OSi bonds,which hinders the substantial formation of metallic In(In^(0))and the subsequent agglomeration.0.6Si/In_(2)O_(3)exhibited CO_(2)conversion rate of10.0 mmol g^(-1)h^(-1)at steady state vs.3.5 mmol g^(-1)h^(-1)on In_(2)O_(3)in CO_(2)hydrogenation.Enhanced steady-state activity was also achieved on Pd-modified catalysts.Compared to the traditional Pd/In_(2)O_(3)catalyst,the methanol production rate of Pd catalyst supported on 0.6Si/In_(2)O_(3)was enhanced by 23%,showing the potential of In_(2)O_(3)modified by SiO_(x)in serving as a platform material.This work provides a promising method to design new In_(2)O_(3)-based catalysts with improved activity and stability in CO_(2)hydrogenation.
文摘The development of an efficient artificial H_(2)O_(2) photosynthesis system is a challenging work using H_(2)O and O_(2) as starting materials.Herein,3D In_(2.77)S_(4) nanoflower precursor was in-situ deposited on K^(+)-doped g-C_(3)N_(4)(KCN)nanosheets using a solvothermal method,then In_(2.77)S_(4)/KCN(IS/KCN)het-erojunction with an intimate interface was obtained after a calcination process.The investigation shows that the photocatalytic H_(2)O_(2) production rate of 50IS/KCN can reach up to 1.36 mmol g^(-1)h^(-1)without any sacrificial reagents under visible light irradiation,which is 9.2 times and 4.1 times higher than that of KCN and In_(2.77)S_(4)/respectively.The enhanced activity of the above composite can be mainly attributed to the S-scheme charge transfer route between KCN and In_(2.77)S_(4) according to density functional theory calculations,electron paramagnetic resonance and free radical capture tests,leading to an expanded light response range and rapid charge separation at their interface,as well as preserving the active electrons and holes for H_(2)O_(2) production.Besides,the unique 3D nanostructure and surface hydrophobicity of IS/KCN facilitate the diffusion and transportation of O_(2) around the active centers,the energy barriers of O_(2) protonation and H_(2)O_(2) desorption steps are ef-fectively reduced over the composite.In addition,this system also exhibits excellent light harvesting ability and stability.This work provides a potential strategy to explore a sustainable H_(2)O_(2) photo-synthesis pathway through the design of heterojunctions with intimate interfaces and desired reac-tion thermodynamics and kinetics.
文摘Z-scheme photocatalytic system has been regarded as a popular field of research in photoelectrochemical(PEC)water splitting.Among the many obstacles facing a Z-scheme photocatalytic system,the analysis methods of interfacial Z-scheme charge transfer still remain a significant challenge.Hence,in this study,CdS/Ti-Fe_(2)O_(3)heterojunction photoanodes are elaborately designed to explore the charge-transfer behavior in PEC water splitting.In this study,photophysical measurements,including the Kelvin probe measurement,surface photovoltage spectroscopy(SPV),and transient photovoltage spectroscopy(TPV),are used to monitor the migration behavior of photogenerated charges at the interface electric field of CdS/Ti-Fe_(2)O_(3)Z-scheme heterojunction photoanodes.The Kelvin probe and SPV measurements demonstrate that CdS/Ti-Fe_(2)O_(3)interfacial driving force favors the rapid transfer of photoexcited electrons to CdS.The double-beam strategy based on TPV indicates that more electrons of Ti-Fe_(2)O_(3)are combined with the holes of CdS owing to the intensive interface electric field.The results of these measurements successfully prove the Z-scheme migration mechanism of CdS/Ti-Fe_(2)O_(3)photoanodes.Benefiting from the desirable charge transfer at the interface electric field,CdS/Ti-Fe_(2)O_(3)photoanodes exhibit superior photocatalytic oxygen evolution reaction performance compared with that of pure Ti-Fe_(2)O_(3).The photocurrent density of the 25CdS/Ti-Fe_(2)O_(3)photoanode reaches 1.94 mA/cm^(2) at 1.23 V versus reversible hydrogen electrode without excess cocatalyst,and it is two times higher than that of pure Ti-Fe_(2)O_(3)photoanode.Therefore,an outstanding strategy is provided in this study to prove the Z-scheme charge-transfer mechanism of photocatalytic systems in PEC water splitting.
基金the founding support from the National Natural Science Foundation of China(21906072 and 22006057)the Natural Science Foundation of Jiangsu Province(BK20190982)+1 种基金“Doctor of Mass entrepreneurship and innovation”Project in Jiangsu ProvinceDoctoral Scientific Research Foundation of Jiangsu University of Science and Technology(China)(1062931806 and 1142931803)。
文摘Photocatalytic water splitting for hydrogen production(H_(2))is one of the main potential applications of photocatalytic technology,which can use solar energy as the energy required for chemical reactions to alleviate the energy crisis.In this work,zero-dimensional/two-dimensional(0D/2D)contact surface CdS/α-Fe_(2)O_(3)(CF)heterojunction photocatalyst was synthesized via a simple solvothermal method.Photocatalytic hydrogen production experiments revealed that the CF-15 sample shows the optimal photocatalytic H_(2)rate(1806μmol·h^(-1)·g^(-1))and apparent quantum efficiency(AQE=13.7%atλ=420 nm).The enhancement of photocatalytic performance is mainly attributed to the contact of 0D/2D interface and the synergistic effect of Z-scheme electron transfer mechanism.This work provides an effective way for modified composite semiconductor photocatalyst by constructing special interface heterojunction to achieve highly efficiently catalysis.
