摘要
金属/金属氧化物复合材料凭借其独特的界面和电子结构已被广泛设计合成,并应用于碱性溶液中电催化析氧反应的电催化剂.然而,如何设计并获得丰富的金属/金属氧化物界面和均匀分散的金属相仍是一个挑战.此外,金属和金属氧化物在增强电催化活性方面的协同机理依然不清晰.本文以金属氧化物为基体,通过锂诱导的转化反应,制备了具有丰富界面和优异电接触的金属/金属氧化物复合物,增加了催化活性位点,并加速了电催化反应过程中的传质.利用该方法制备出的NiCo/NiCo2O4,NiMn/Ni Mn2O4和CoMn/CoMn2O4催化剂的析氧性能有显著提升.通过原位X射线吸收光谱和原位拉曼光谱技术,本文探索了复合催化剂的催化机理,揭示了析氧反应中的催化活性中心以及金属与金属氧化物之间的协同作用机理.密度泛函理论+U(DFT+U)计算证实了金属/金属氧化物材料中的金属组分可以优化催化反应路径并降低反应势垒,从而加速电催化动力学.
Due to the unique interface and electronic structure,metal/metal oxide composite electrocatalysts have been designed and exploited for electrocatalytic oxygen evolution reaction(OER)in alkaline solution.However,how to fabricate metal/metal oxides with abundant interfaces and well-dispersed metal phases is a challenge,and the synergistic effect between metal and metal oxides on boosting the electrocatalytic activities is still ambiguous.Herein,by controlling the lithium-induced conversion reaction of metal oxides,metal/metal oxide composites with plentiful interfaces and excellent electrical interconnection are fabricated,which can enhance the active sites,and accelerate the mass transfer during the electrocatalytic reaction.As a result,the electrocatalytic oxygen evolution activities of the as-fabricated metal/metal oxide composite catalysts including NiCo/NiCo2O4,NiMn/NiMn2O4 and CoMn/CoMn2O4 are greatly improved.The catalytic mechanism is also explored using the in-situ X-ray and Raman spectroscopic tracking to uncover the real active centers and the synergistic effect between the metal and metal oxides during water oxidation.Density functional theory plus U(DFT+U)calculation confirms the metal in the composite can optimize the catalytic reaction path and reduce the reaction barrier,thus boosting the electrocatalytic kinetics.
作者
Shahid Khan
王超
陆豪量
曹宇锋
冒泽阳
晏成林
王显福
Shahid Khan;Chao Wang;Haoliang Lu;Yufeng Cao;Zeyang Mao;Chenglin Yan;Xianfu Wang(Soochow Institute for Energy and Materials Innovations,College of Energy,Soochow University,Suzhou,215006,China;State Key Laboratory of Electronic Thin Films and Integrated Devices,University of Electronic Science and Technology of China,Chengdu,610054,China;School of Chemical and Environmental Engineering,College of Chemistry,Chemical Engineering and Material Science,Soochow University,Suzhou,215123,China)
基金
the National Natural Science Foundation of China(21603157)
Young Elite Scientists Sponsorship Program by CAST(2018QNRC001)
the support of Suzhou Key Laboratory for Advanced Carbon Materials and Wearable Energy Technologies and Soochow University Analysis and Testing Center。
