Direct electrolytic splitting of seawater for the production of H2 using ocean energy is a promising technology that can help achieve carbon neutrality.However,owing to the high concentrations of chlorine ions in seaw...Direct electrolytic splitting of seawater for the production of H2 using ocean energy is a promising technology that can help achieve carbon neutrality.However,owing to the high concentrations of chlorine ions in seawater,the chlorine evolution reaction always competes with the oxygen evolution reaction(OER)at the anode,and chloride corrosion occurs on both the anode and cathode.Thus,effective electrocatalysts with high selectivity toward the OER and excellent resistance to chloride corrosion should be developed.In this critical review,we focus on the prospects of state-of-the-art metal-oxide electrocatalysts,including noble metal oxides,non-noble metal oxides and their compounds,and spinel-and perovskite-type oxides,for seawater splitting.We elucidate their chemical properties,excellent OER selectivity,outstanding anti-chlorine-corrosion performance,and reaction mechanisms.In particular,we review metal oxides that operate at high current densities,near industrial application levels,based on special catalyst design strategies.展开更多
Earth-abundant seawater resource has become an attractive candidate to produce hydrogen from electrolysis,which is of great significance to realize hydrogen economy and carbon neutrality.Nonetheless,developing highly ...Earth-abundant seawater resource has become an attractive candidate to produce hydrogen from electrolysis,which is of great significance to realize hydrogen economy and carbon neutrality.Nonetheless,developing highly active and stable electrocatalysts to meet the needs of highly effective seawater splitting is still challenging for the sluggish oxygen evolution dynamics and the existed competitive reaction of chlorine evolution reaction(CER).To this end,some newly-developed electrocatalysts with superior performance,such as noble metals,alloy,transition metals,oxides,carbides,nitrides,phosphides,and so on,have been synthesized for the seawater splitting in recent years.This review starts from the historical background and fundamental mechanisms,and summarizes the most recent progress in the development of seawater electrolysis technologies.Some existing issues in the process of seawater electrolysis are enumerated and the corresponded solutions are presented.The future of hydrogen production from seawater electrolysis,especially the design and synthesis of novel catalysts for seawater electrolysis,is prospected.展开更多
Spinel cobalt oxide(Co_(3)O_(4)),consisting of tetrahedral Co^(2+)(CoTd)and octahedral Co^(3+)(CoOh),is considered as promising earth-abundant electrocatalyst for chlorine evolution reaction(CER).Identifying the catal...Spinel cobalt oxide(Co_(3)O_(4)),consisting of tetrahedral Co^(2+)(CoTd)and octahedral Co^(3+)(CoOh),is considered as promising earth-abundant electrocatalyst for chlorine evolution reaction(CER).Identifying the catalytic contribution of geometric Co site in the electrocatalytic CER plays a pivotal role to precisely modulate electronic configuration of active Co sites to boost CER.Herein,combining density functional theory calculations and experiment results assisted with operando analysis,we found that the Co_(Oh) site acts as the main active site for CER in spinel Co_(3)O_(4),which shows better Cl^(-)adsorption and more moderate intermediate adsorption toward CER than CoTd site,and does not undergo redox transition under CER condition at applied potentials.Guided by above findings,the oxygen vacancies were further introduced into the Co_(3)O_(4) to precisely manipulate the electronic configuration of Co_(Oh) to boost Cl^(-)adsorption and optimize the reaction path of CER and thus to enhance the intrinsic CER activity significantly.Our work figures out the importance of geometric configuration dependent CER activity,shedding light on the rational design of advanced electrocatalysts from geometric configuration optimization at the atomic level.展开更多
The chlorine evolution reaction(CER)is a crucial step in the production of chlorine gas and active chlorine by chlor-alkali electrolysis.Currently,the endeavor to fabricate electrodes capable of yielding high current ...The chlorine evolution reaction(CER)is a crucial step in the production of chlorine gas and active chlorine by chlor-alkali electrolysis.Currently,the endeavor to fabricate electrodes capable of yielding high current density at minimal overpotential remains a central challenge in advancing the realm of chlorine evolution reactions.Here,we grow TiO_(2)and RuO_(2)on MXene@carbon cloth(CC)through the favorable affinity and induced deposition effect between the surface functional groups of MXene and the metal.A self-supported electrode(RuTiO_(2)/MXene@CC)with strong binding at the electrocatalyst-support interface and weak adhesion at electrocatalyst-bubble interface is constructed.The RuTiO_(2)/MXene@CC can reduce the electron density of RuO_(2)by regulating the electron redistribution at the heterogeneous interface,thus enhancing the adsorption of Cl−.RuTiO_(2)/MXene@CC could achieve a high current density of 1000 mA·cm^(−2)at a small overpotential of 220 mV,superior to commercial dimensionally stable anodes(DSA).This study provides a new strategy for constructing efficient CER catalysts at high current density.展开更多
Chlorine(Cl2)is one of the most important chemicals produced by the electrolysis of brine solutions and is a key raw material for many areas of industrial chemistry.For nearly half a century,dimensionally stable anode...Chlorine(Cl2)is one of the most important chemicals produced by the electrolysis of brine solutions and is a key raw material for many areas of industrial chemistry.For nearly half a century,dimensionally stable anode(DSA)made from a mixture of RuO_(2) and TiO_(2) solid oxides coated on Ti substrate has been the most widely used electrode for chlorine evolution reaction(CER).In harsh operating environments,the stability of DSAs remains a major challenge greatly affecting their lifetime.The deactivation of DSAs significantly increases the cost of the chlor-alkali industry due to the corrosion of Ru and the formation of the passivation layer TiO_(2).Therefore,it is urgent to develop catalysts with higher activity and stability,which requires a thorough understanding of the deactivation mechanism of DSA catalysts.This paper reviews existing references on the deactivation mechanisms of DSA catalysts,including both experimental and theoretical studies.Studies on how CER selectivity affects electrode stability are also discussed.Furthermore,studies on the effects of the preparation process,elemental composition,and surface/interface structures on the DSA stability and corresponding improvement strategies are summarized.The development of other non-DSA-type catalysts with comparable stability is also reviewed,and future opportunities in this exciting field are also outlined.展开更多
为了提高电极的析氯活性并降低生产成本,采用热分解法制备低Ir掺杂的Ti/IrRuSnSbO_(x)电极,通过材料表征和电化学测试研究了电极的微观结构和电化学性能。结果表明,在0~30%范围内,随着Ir摩尔分数的增加,表面裂纹逐渐增多且加深,增大了...为了提高电极的析氯活性并降低生产成本,采用热分解法制备低Ir掺杂的Ti/IrRuSnSbO_(x)电极,通过材料表征和电化学测试研究了电极的微观结构和电化学性能。结果表明,在0~30%范围内,随着Ir摩尔分数的增加,表面裂纹逐渐增多且加深,增大了内表面活性面积占比,而析氯活性和析氯效率均先升高后降低,其中,掺杂摩尔分数10%的电极具有最低的电荷转移电阻、最高的反应速率,电流密度为10 mA/cm^(2)时析氯电位为1.118 V vs.SCE,析氯效率为99.6%。展开更多
The oxygen evolution reaction(OER) plays a crucial role in many electrochemical energy technologies,and creating multiple beneficial factors for OER catalysis is desirable for achieving high catalytic efficiency.Here,...The oxygen evolution reaction(OER) plays a crucial role in many electrochemical energy technologies,and creating multiple beneficial factors for OER catalysis is desirable for achieving high catalytic efficiency.Here,we highlight a new halogen-chlorine(Cl)-anion doping strategy to boost the OER activity of perovskite oxides.As a proof-of-concept,proper Cl doping at the oxygen site of LaFeO3(LFO) perovskite can induce multiple favorable characteristics for catalyzing the OER,including rich oxygen vacancies,increased electrical conductivity and enhanced Fe-O covalency.Benefiting from these factors,the LaFeO2.9-δCl0.1(LFOCl) perovskite displays significant intrinsic activity enhancement by a factor of around three relative to its parent LFO.This work uncovers the effect of Cl-anion doping in perovskites on promoting OER performance and paves a new way to design highly efficient electrocatalysts.展开更多
Rationally manipulating the in‐situ formed catalytically active surface of catalysts remains a great challenge for a highly efficient water electrolysis.Here,we report a cationic oxidation method which can adjust the...Rationally manipulating the in‐situ formed catalytically active surface of catalysts remains a great challenge for a highly efficient water electrolysis.Here,we report a cationic oxidation method which can adjust the leaching of the in‐situ catalyst and promote the reconstruction of dynamic surface for the oxygen evolution reaction(OER).The chlorine doping can reduce the possibility of triggering in‐situ cobalt oxidation and chlorine leaching,leading to a transformation of the surface chlorine doped LaCoO_(3)(Cl‐LaCoO_(3))into an intricate amorphous(oxygen)hydroxide phase.And thus,Cl‐LaCoO_(3)nanocrystals shows an ultralow overpotential of 342 mV at the current density of 10 mA cm^(–2)and Tafel slope of 76.2 mV dec–1.Surface reconstructed Cl‐LaCoO_(3)is better than many of the most advanced OER catalysts and has proven significant stability.This work provides a new prospect for designing a high‐efficiency electrocatalyst with optimized perovskite‐structure in renewable energy system.展开更多
Scaled-up industrial water electrolysis equipment that can be used with abundant seawater is key for affordable hydrogen production.The search for highly stable,dynamic,and economical electrocatalysts could have a sig...Scaled-up industrial water electrolysis equipment that can be used with abundant seawater is key for affordable hydrogen production.The search for highly stable,dynamic,and economical electrocatalysts could have a significant impact on hydrogen commercialization.Herein,we prepared energy-efficient,scalable,and engineering electronic structure modulated Mn-Ni bimetal oxides(Mn_(0.25)Ni_(0.75)O)through simple hydrothermal followed by calcination method.As-optimized Mn_(0.25)Ni_(0.75)O displayed enhanced oxygen and hydrogen evolution reaction(OER and HER)performance with overpotentials of 266 and115 mV at current densities of 10 mA cm^(-2)in alkaline KOH added seawater electrolyte solution.Additionally,Mn-Ni oxide catalytic benefits were attributed to the calculated electronic configurations and Gibbs free energy for OER,and HER values were estimated using first principles calculations.In real-time practical application,we mimicked industrial operating conditions with modified seawater electrolysis using Mn_(0.25)Ni_(0.75)O‖Mn_(0.25)Ni_(0.75)O under various temperature conditions,which performs superior to the commercial IrO_(2)‖Pt-C couple.These findings demonstrate an inexpensive and facile technique for feasible large-scale hydrogen production.展开更多
Electrochemical technologies for the on-site treatment of spent acid etchant have received great attention due their ease of operation and economic benefits. On the other hand, a large amount of Cl2 is generated durin...Electrochemical technologies for the on-site treatment of spent acid etchant have received great attention due their ease of operation and economic benefits. On the other hand, a large amount of Cl2 is generated during the electrolysis process, which leads to potential environmental risks. In the present work, a novel threecompartment ceramic membrane flow reactor, including a cathode chamber, an anode chamber, and a gas absorption chamber was developed. The three chambers were divided by an Al2O3 ceramic membrane and a breathable hydrophobic anode diffusion electrode(ADE). The Cl2 evolution onset potential of the ADE was increased to 1.19 V from 1.05 V of the graphite felt, effectively inhibiting the chlorine evolution reaction(CER).The anode-generated Cl2 diffused into the gas absorption chamber through the ADE and was eventually consumed by the H2O2 adsorbent. Cu could be recovered without emitting chlorine due to the special structure of reactor. The current efficiency of copper precipitation and cathode reduction from Cu2+to Cu+reached 97.7%at a working current of 150 m A. These results indicated that the novel membrane reactor had high potential for application in the copper recovery industry.展开更多
基金This work is supported by ZiQoo Chemical Co.Ltd.,Japan,and Hydrogen Energy Systems Society of Japan.Chen and Feng gratefully acknowledge the State Scholarship Fund of China Scholarship Council,China.Kitiphatpiboon gratefully acknowledges MEXT of Japan for the scholarship,Japan.
文摘Direct electrolytic splitting of seawater for the production of H2 using ocean energy is a promising technology that can help achieve carbon neutrality.However,owing to the high concentrations of chlorine ions in seawater,the chlorine evolution reaction always competes with the oxygen evolution reaction(OER)at the anode,and chloride corrosion occurs on both the anode and cathode.Thus,effective electrocatalysts with high selectivity toward the OER and excellent resistance to chloride corrosion should be developed.In this critical review,we focus on the prospects of state-of-the-art metal-oxide electrocatalysts,including noble metal oxides,non-noble metal oxides and their compounds,and spinel-and perovskite-type oxides,for seawater splitting.We elucidate their chemical properties,excellent OER selectivity,outstanding anti-chlorine-corrosion performance,and reaction mechanisms.In particular,we review metal oxides that operate at high current densities,near industrial application levels,based on special catalyst design strategies.
基金supported by ZiQoo Chemical Co.Ltd.,Japan,and Hydrogen Energy Systems Society of Japan.Feng and Chen gratefully acknowledge the State Scholarship Fund of China Scholarship Council,China.
文摘Earth-abundant seawater resource has become an attractive candidate to produce hydrogen from electrolysis,which is of great significance to realize hydrogen economy and carbon neutrality.Nonetheless,developing highly active and stable electrocatalysts to meet the needs of highly effective seawater splitting is still challenging for the sluggish oxygen evolution dynamics and the existed competitive reaction of chlorine evolution reaction(CER).To this end,some newly-developed electrocatalysts with superior performance,such as noble metals,alloy,transition metals,oxides,carbides,nitrides,phosphides,and so on,have been synthesized for the seawater splitting in recent years.This review starts from the historical background and fundamental mechanisms,and summarizes the most recent progress in the development of seawater electrolysis technologies.Some existing issues in the process of seawater electrolysis are enumerated and the corresponded solutions are presented.The future of hydrogen production from seawater electrolysis,especially the design and synthesis of novel catalysts for seawater electrolysis,is prospected.
基金the National Natural Science Foundation of China(U21A20286,22206054 and 21805069)Natural Science Foundation of Hubei(2021CFB094)the Fundamental Research Funds for the Central China Normal University(CCNU)for financial support。
文摘Spinel cobalt oxide(Co_(3)O_(4)),consisting of tetrahedral Co^(2+)(CoTd)and octahedral Co^(3+)(CoOh),is considered as promising earth-abundant electrocatalyst for chlorine evolution reaction(CER).Identifying the catalytic contribution of geometric Co site in the electrocatalytic CER plays a pivotal role to precisely modulate electronic configuration of active Co sites to boost CER.Herein,combining density functional theory calculations and experiment results assisted with operando analysis,we found that the Co_(Oh) site acts as the main active site for CER in spinel Co_(3)O_(4),which shows better Cl^(-)adsorption and more moderate intermediate adsorption toward CER than CoTd site,and does not undergo redox transition under CER condition at applied potentials.Guided by above findings,the oxygen vacancies were further introduced into the Co_(3)O_(4) to precisely manipulate the electronic configuration of Co_(Oh) to boost Cl^(-)adsorption and optimize the reaction path of CER and thus to enhance the intrinsic CER activity significantly.Our work figures out the importance of geometric configuration dependent CER activity,shedding light on the rational design of advanced electrocatalysts from geometric configuration optimization at the atomic level.
基金the National Natural Science Foundation of China(Nos.21971132,52072197,and 52272222)Youth Innovation and Technology Foundation of Shandong Higher Education Institutions,China(No.2019KJC004)+5 种基金Major Scientific and Technological Innovation Project(No.2019JZZY020405)Major Basic Research Program of Natural Science Foundation of Shandong Province(No.ZR2020ZD09)Taishan Scholar Young Talent Program(No.tsqn201909114)the 111 Project of China(No.D20017)Shandong Province Double-Hundred Talent Plan(No.WST2020003)State Key Laboratory of Heavy Oil Processing(No.SKLHOP202202006).
文摘The chlorine evolution reaction(CER)is a crucial step in the production of chlorine gas and active chlorine by chlor-alkali electrolysis.Currently,the endeavor to fabricate electrodes capable of yielding high current density at minimal overpotential remains a central challenge in advancing the realm of chlorine evolution reactions.Here,we grow TiO_(2)and RuO_(2)on MXene@carbon cloth(CC)through the favorable affinity and induced deposition effect between the surface functional groups of MXene and the metal.A self-supported electrode(RuTiO_(2)/MXene@CC)with strong binding at the electrocatalyst-support interface and weak adhesion at electrocatalyst-bubble interface is constructed.The RuTiO_(2)/MXene@CC can reduce the electron density of RuO_(2)by regulating the electron redistribution at the heterogeneous interface,thus enhancing the adsorption of Cl−.RuTiO_(2)/MXene@CC could achieve a high current density of 1000 mA·cm^(−2)at a small overpotential of 220 mV,superior to commercial dimensionally stable anodes(DSA).This study provides a new strategy for constructing efficient CER catalysts at high current density.
文摘Chlorine(Cl2)is one of the most important chemicals produced by the electrolysis of brine solutions and is a key raw material for many areas of industrial chemistry.For nearly half a century,dimensionally stable anode(DSA)made from a mixture of RuO_(2) and TiO_(2) solid oxides coated on Ti substrate has been the most widely used electrode for chlorine evolution reaction(CER).In harsh operating environments,the stability of DSAs remains a major challenge greatly affecting their lifetime.The deactivation of DSAs significantly increases the cost of the chlor-alkali industry due to the corrosion of Ru and the formation of the passivation layer TiO_(2).Therefore,it is urgent to develop catalysts with higher activity and stability,which requires a thorough understanding of the deactivation mechanism of DSA catalysts.This paper reviews existing references on the deactivation mechanisms of DSA catalysts,including both experimental and theoretical studies.Studies on how CER selectivity affects electrode stability are also discussed.Furthermore,studies on the effects of the preparation process,elemental composition,and surface/interface structures on the DSA stability and corresponding improvement strategies are summarized.The development of other non-DSA-type catalysts with comparable stability is also reviewed,and future opportunities in this exciting field are also outlined.
文摘为了提高电极的析氯活性并降低生产成本,采用热分解法制备低Ir掺杂的Ti/IrRuSnSbO_(x)电极,通过材料表征和电化学测试研究了电极的微观结构和电化学性能。结果表明,在0~30%范围内,随着Ir摩尔分数的增加,表面裂纹逐渐增多且加深,增大了内表面活性面积占比,而析氯活性和析氯效率均先升高后降低,其中,掺杂摩尔分数10%的电极具有最低的电荷转移电阻、最高的反应速率,电流密度为10 mA/cm^(2)时析氯电位为1.118 V vs.SCE,析氯效率为99.6%。
基金financially supported by the Australian Research Council (Discovery Early Career Researcher Award No. DE190100005)the support of the Australian Research Council (Grant No. FT160100207)the ontinued support from the Queensland University of Technology (QUT) through the centre for Materials Science。
文摘The oxygen evolution reaction(OER) plays a crucial role in many electrochemical energy technologies,and creating multiple beneficial factors for OER catalysis is desirable for achieving high catalytic efficiency.Here,we highlight a new halogen-chlorine(Cl)-anion doping strategy to boost the OER activity of perovskite oxides.As a proof-of-concept,proper Cl doping at the oxygen site of LaFeO3(LFO) perovskite can induce multiple favorable characteristics for catalyzing the OER,including rich oxygen vacancies,increased electrical conductivity and enhanced Fe-O covalency.Benefiting from these factors,the LaFeO2.9-δCl0.1(LFOCl) perovskite displays significant intrinsic activity enhancement by a factor of around three relative to its parent LFO.This work uncovers the effect of Cl-anion doping in perovskites on promoting OER performance and paves a new way to design highly efficient electrocatalysts.
文摘Rationally manipulating the in‐situ formed catalytically active surface of catalysts remains a great challenge for a highly efficient water electrolysis.Here,we report a cationic oxidation method which can adjust the leaching of the in‐situ catalyst and promote the reconstruction of dynamic surface for the oxygen evolution reaction(OER).The chlorine doping can reduce the possibility of triggering in‐situ cobalt oxidation and chlorine leaching,leading to a transformation of the surface chlorine doped LaCoO_(3)(Cl‐LaCoO_(3))into an intricate amorphous(oxygen)hydroxide phase.And thus,Cl‐LaCoO_(3)nanocrystals shows an ultralow overpotential of 342 mV at the current density of 10 mA cm^(–2)and Tafel slope of 76.2 mV dec–1.Surface reconstructed Cl‐LaCoO_(3)is better than many of the most advanced OER catalysts and has proven significant stability.This work provides a new prospect for designing a high‐efficiency electrocatalyst with optimized perovskite‐structure in renewable energy system.
基金supported by the GEONJI Research support programsupported by Basic Science Research through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF-2021R1I1A1A01050905)+1 种基金supported by grants from the Medical Research Center Program(NRF-2017R1A5A2015061)through the National Research Foundation(NRF),which is funded by the Korean government(MSIP)supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT and Future Planning(NRF-2020R1A2B5B01001458)。
文摘Scaled-up industrial water electrolysis equipment that can be used with abundant seawater is key for affordable hydrogen production.The search for highly stable,dynamic,and economical electrocatalysts could have a significant impact on hydrogen commercialization.Herein,we prepared energy-efficient,scalable,and engineering electronic structure modulated Mn-Ni bimetal oxides(Mn_(0.25)Ni_(0.75)O)through simple hydrothermal followed by calcination method.As-optimized Mn_(0.25)Ni_(0.75)O displayed enhanced oxygen and hydrogen evolution reaction(OER and HER)performance with overpotentials of 266 and115 mV at current densities of 10 mA cm^(-2)in alkaline KOH added seawater electrolyte solution.Additionally,Mn-Ni oxide catalytic benefits were attributed to the calculated electronic configurations and Gibbs free energy for OER,and HER values were estimated using first principles calculations.In real-time practical application,we mimicked industrial operating conditions with modified seawater electrolysis using Mn_(0.25)Ni_(0.75)O‖Mn_(0.25)Ni_(0.75)O under various temperature conditions,which performs superior to the commercial IrO_(2)‖Pt-C couple.These findings demonstrate an inexpensive and facile technique for feasible large-scale hydrogen production.
基金Supported by the National Natural Science Foundation of China(21838005,21676139)the Higher Education Natural Science Foundation of Jiangsu Province(15KJA530001)+1 种基金the Key Scientific Research and Development Projects of Jiangsu Province(BE201800901)Research Fund of State Key Laboratory of MaterialsOriented Chemical Engineering(ZK201604).
文摘Electrochemical technologies for the on-site treatment of spent acid etchant have received great attention due their ease of operation and economic benefits. On the other hand, a large amount of Cl2 is generated during the electrolysis process, which leads to potential environmental risks. In the present work, a novel threecompartment ceramic membrane flow reactor, including a cathode chamber, an anode chamber, and a gas absorption chamber was developed. The three chambers were divided by an Al2O3 ceramic membrane and a breathable hydrophobic anode diffusion electrode(ADE). The Cl2 evolution onset potential of the ADE was increased to 1.19 V from 1.05 V of the graphite felt, effectively inhibiting the chlorine evolution reaction(CER).The anode-generated Cl2 diffused into the gas absorption chamber through the ADE and was eventually consumed by the H2O2 adsorbent. Cu could be recovered without emitting chlorine due to the special structure of reactor. The current efficiency of copper precipitation and cathode reduction from Cu2+to Cu+reached 97.7%at a working current of 150 m A. These results indicated that the novel membrane reactor had high potential for application in the copper recovery industry.
