氧电催化一般涉及到氧还原反应(ORR)和氧析出应(OER),是诸如燃料电池,金属空气电池和水电解池等能源转换与存储技术的关键步骤.其中,可充电的金属锌空气电池具有较高的能量密度,开发成本较低,运行安全且环境友好.然而,开发并采用高效,...氧电催化一般涉及到氧还原反应(ORR)和氧析出应(OER),是诸如燃料电池,金属空气电池和水电解池等能源转换与存储技术的关键步骤.其中,可充电的金属锌空气电池具有较高的能量密度,开发成本较低,运行安全且环境友好.然而,开发并采用高效,低成本且储量丰富的催化材料代替贵金属基电催化剂,仍旧是现阶段尚未完全解决的问题和挑战.最近,金属有机框架(MOFs)以及碳基的金属有机框架衍生物作为高效电催化剂,因其超乎寻常的形貌,结构,组分和功能性的可调节能力,已经逐渐引起了广泛的关注和研究兴趣.因此,本文报道了一种泡沫镍负载的二维金属有机框架及其衍生物耦合阵列作为无粘结剂型ORR/OER双效催化剂,能够实现高比表面积,高电导率和高双功能性,同时避免了使用有机粘结剂的复杂制备过程和不可避免的电池性能影响.与传统设计不同,本文主要通过集成各司其职的不同功能组分并充分暴露电化学活性面积来提高双效电极的整体活性.电化学测试结果表明,耦合阵列电极(R-NCM)相比于MOFs阵列(NCM)和MOFs衍生物阵列(A-NCM)等对比电极,具有显著提高的双效氧电极性能,氧还原反应的起峰电位约为0.90 V,而氧析出反应电流密度达到100 m Acm-2时的过电势为319 m V.由于其在生长–热裂解–再生长过程中所具有的稳定的站立多级二维纳米片结构,所制备的双效氧电极材料表现出显著增强的双官能团性,电化学活性面积,反应动力学和稳定性,并可进一步用于可充电的金属锌空气电池(ZABs).考虑到制备过程的可行性与简洁性,所提出的生长–热裂解–再生长策略不仅能够用于耦合型分级纳米片阵列结构的合成,还能为设计开发相关能源电化学装置的高活性电极结构提供借鉴.展开更多
Being a typical state of the art heterogeneous catalyst,supported noble metal catalyst often demonstrates enhanced catalytic properties.However,a facile synthetic method for realizing large-scale and low-cost supporte...Being a typical state of the art heterogeneous catalyst,supported noble metal catalyst often demonstrates enhanced catalytic properties.However,a facile synthetic method for realizing large-scale and low-cost supported noble metal catalyst is strictly indispensable.To this end,by making use of the strong metal-support interaction(SMSI)and mechanochemical reaction,we introduce an efficient synthetic route to obtain ultrafine Pt and Ir nanoclusters immobilized on diverse substrates by wet chemical milling.We further demonstrate the scaling-up effect of our approach by large-scale ball-milling production of Pt nanoclusters immobilized on TiO_(2)substrate.The synthesized Pt/Ir@Co_(3)O_(4)catalysts exhibit superior oxygen evolution reaction(OER)performance with only 230 and 290 mV overpotential to achieve current density of 10 and 100 mA·cm^(-2),beating the catalytic performance of Co_(3)O_(4)supported Pt or Ir clusters and commercial Ir/C.It is envisioned that the present work strategically directs facile ways for fabricating supported noble metal heterogeneous catalysts.展开更多
Cluster catalysts are rapidly growing into an important sub-field in heterogeneous catalysis,owing to their distinct geometric structure,neighboring metal sites,and unique electronic structure.Although the thermodynam...Cluster catalysts are rapidly growing into an important sub-field in heterogeneous catalysis,owing to their distinct geometric structure,neighboring metal sites,and unique electronic structure.Although the thermodynamics and kinetics of the formation of nanoparticles have been largely investigated,the precise synthesis of clusters in wet chemical methods still faces great challenges.In the study,a quenching strategy of asymmetric temperature in solution for the rapid generation of vacancy-defect rich clusters is reported.The quenching process can be used to synthesize multitudinous metal compound clusters,including metal oxides,fluorides,oxygen-sulfur compounds,and tungstate.For oxygen evolution reaction(OER),IrO_(2)clusters with abundant oxygen vacancies were obtained and uniformly dispersed in the solution.Compared to commercial IrO_(2),the prepared IrO_(2)cluster can be directly loaded on carbon paper and used as binder-free electrodes,which exhibit higher OER activity and long-term operational stability in alkaline electrolytes.The quenching strategy provides a simple and efficient method for the synthesis of clusters,which has tremendous potential for industrial-scale preparation and application,especially can be further applied to flow electrochemical generators.展开更多
文摘氧电催化一般涉及到氧还原反应(ORR)和氧析出应(OER),是诸如燃料电池,金属空气电池和水电解池等能源转换与存储技术的关键步骤.其中,可充电的金属锌空气电池具有较高的能量密度,开发成本较低,运行安全且环境友好.然而,开发并采用高效,低成本且储量丰富的催化材料代替贵金属基电催化剂,仍旧是现阶段尚未完全解决的问题和挑战.最近,金属有机框架(MOFs)以及碳基的金属有机框架衍生物作为高效电催化剂,因其超乎寻常的形貌,结构,组分和功能性的可调节能力,已经逐渐引起了广泛的关注和研究兴趣.因此,本文报道了一种泡沫镍负载的二维金属有机框架及其衍生物耦合阵列作为无粘结剂型ORR/OER双效催化剂,能够实现高比表面积,高电导率和高双功能性,同时避免了使用有机粘结剂的复杂制备过程和不可避免的电池性能影响.与传统设计不同,本文主要通过集成各司其职的不同功能组分并充分暴露电化学活性面积来提高双效电极的整体活性.电化学测试结果表明,耦合阵列电极(R-NCM)相比于MOFs阵列(NCM)和MOFs衍生物阵列(A-NCM)等对比电极,具有显著提高的双效氧电极性能,氧还原反应的起峰电位约为0.90 V,而氧析出反应电流密度达到100 m Acm-2时的过电势为319 m V.由于其在生长–热裂解–再生长过程中所具有的稳定的站立多级二维纳米片结构,所制备的双效氧电极材料表现出显著增强的双官能团性,电化学活性面积,反应动力学和稳定性,并可进一步用于可充电的金属锌空气电池(ZABs).考虑到制备过程的可行性与简洁性,所提出的生长–热裂解–再生长策略不仅能够用于耦合型分级纳米片阵列结构的合成,还能为设计开发相关能源电化学装置的高活性电极结构提供借鉴.
基金This study was supported by the National Natural Science Foundations of China(Nos.51902027,61874014,61874013,51788104,61974011 and 61976025)the Basic Science Center Program of the National Natural Science Foundation of China(No.51788104)+2 种基金National Basic Research of China(Nos.2016YFE0102200 and 2018YFB0104404)Beijing Natural Science Foundation(No.JQ19005)Fund of State Key Laboratory of Information Photonics and Optical Communications(Beijing University of Posts and Telecommunications,China).
文摘Being a typical state of the art heterogeneous catalyst,supported noble metal catalyst often demonstrates enhanced catalytic properties.However,a facile synthetic method for realizing large-scale and low-cost supported noble metal catalyst is strictly indispensable.To this end,by making use of the strong metal-support interaction(SMSI)and mechanochemical reaction,we introduce an efficient synthetic route to obtain ultrafine Pt and Ir nanoclusters immobilized on diverse substrates by wet chemical milling.We further demonstrate the scaling-up effect of our approach by large-scale ball-milling production of Pt nanoclusters immobilized on TiO_(2)substrate.The synthesized Pt/Ir@Co_(3)O_(4)catalysts exhibit superior oxygen evolution reaction(OER)performance with only 230 and 290 mV overpotential to achieve current density of 10 and 100 mA·cm^(-2),beating the catalytic performance of Co_(3)O_(4)supported Pt or Ir clusters and commercial Ir/C.It is envisioned that the present work strategically directs facile ways for fabricating supported noble metal heterogeneous catalysts.
基金the National Natural Science Foundation of China(Nos.51902027,51788104,61874014,61874013,61974011,and 61976025)the National Basic Research of China(Nos.2016YFE0102200 and 2018YFB0104404)+4 种基金Beijing Natural Science Foundation(No.JQ19005)Fund of State Key Laboratory of Information Photonics and Optical Communications(Beijing University of Posts and Telecommunications,China),BUPT Excellent Ph.D.Students Foundation(No.CX2020119)Guangdong Hydrogen Energy Institute of WHUT under Guangdong Key Areas Research and Development Program(No.2019B090909003)Guangdong Basic and Applied Basic Research Foundation(No.2020B1515120042)Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory(No.XHD2020-002).
文摘Cluster catalysts are rapidly growing into an important sub-field in heterogeneous catalysis,owing to their distinct geometric structure,neighboring metal sites,and unique electronic structure.Although the thermodynamics and kinetics of the formation of nanoparticles have been largely investigated,the precise synthesis of clusters in wet chemical methods still faces great challenges.In the study,a quenching strategy of asymmetric temperature in solution for the rapid generation of vacancy-defect rich clusters is reported.The quenching process can be used to synthesize multitudinous metal compound clusters,including metal oxides,fluorides,oxygen-sulfur compounds,and tungstate.For oxygen evolution reaction(OER),IrO_(2)clusters with abundant oxygen vacancies were obtained and uniformly dispersed in the solution.Compared to commercial IrO_(2),the prepared IrO_(2)cluster can be directly loaded on carbon paper and used as binder-free electrodes,which exhibit higher OER activity and long-term operational stability in alkaline electrolytes.The quenching strategy provides a simple and efficient method for the synthesis of clusters,which has tremendous potential for industrial-scale preparation and application,especially can be further applied to flow electrochemical generators.
