Atomic Metal-Support Interaction Enables Reconstruction-Free Dual-Site Electrocatalyst
Atomic Metal-Support Interaction Enables Reconstruction-Free Dual-Site Electrocatalyst
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DOI：
10.1021/jacs.1c08890
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发表时间：
2021-12-22
影响因子：
15
通讯作者：
Chen, Hao Ming
中科院分区：
文献类型：
--
作者：
Sun, Huachuan;Tung, Ching-Wei;Chen, Hao Ming
真实的双功能电催化剂必须在反应过程中和反应后表现出稳定的构型，没有不可逆的结构转变或表面重构。否则，它们可以被称为“预催化剂”而不是真实的催化剂。在本文中，通过强烈的原子金属-载体相互作用，将原子分散的Ru修饰到镍-钒层状双氢氧化物（LDH）支架上的单原子分散催化剂可以表现出优异的HER和OER活性。原位X射线吸收光谱和操作拉曼光谱研究表明，Ru原子在镍钒LDH表面的存在对稳定富悬键表面起着至关重要的作用，并进一步导致无重构表面。通过由镍-钒LDH提供的强金属-载体相互作用，显著的相互作用可以稳定反应性原子Ru位点以达到朝向阴极HER的氧化态的小波动而没有重建，而原子Ru位可以稳定Ni位，从而对阳极OER期间由氧化Ni位引起的键收缩和结构畸变具有更大的结构容忍度，并提高氧化态Ni位的增加有助于其上级OER性能。与许多双功能催化剂不同，所提出的Ru/Ni 3V-LDH具有稳定的双反应位点的特征，存在强的金属-载体相互作用（即，Ru和Ni位点）的水裂解中的单独催化，并显示被称为真实的双功能电催化剂。
Real bifunctional electrocatalysts for hydrogen evolution reaction and oxygen evolution reaction have to be the ones that exhibit a steady configuration during/after reaction without irreversible structural transformation or surface reconstruction. Otherwise, they can be termed as "precatalysts" rather than real catalysts. Herein, through a strongly atomic metal-support interaction, single-atom dispersed catalysts decorating atomically dispersed Ru onto a nickel-vanadium layered double hydroxide (LDH) scaffold can exhibit excellent HER and OER activities. Both in situ X-ray absorption spectroscopy and operando Raman spectroscopic investigation clarify that the presence of atomic Ru on the surface of nickel-vanadium LDH is playing an imperative role in stabilizing the dangling bond-rich surface and further leads to a reconstruction-free surface. Through strong metal-support interaction provided by nickel-vanadium LDH, the significant interplay can stabilize the reactive atomic Ru site to reach a small fluctuation in oxidation state toward cathodic HER without reconstruction, while the atomic Ru site can stabilize the Ni site to have a greater structural tolerance toward both the bond constriction and structural distortion caused by oxidizing the Ni site during anodic OER and boost the oxidation state increase in the Ni site that contributes to its superior OER performance. Unlike numerous bifunctional catalysts that have suffered from the structural reconstruction/transformation for adapting the HER/OER cycles, the proposed Ru/Ni3V-LDH is characteristic of steady dual reactive sites with the presence of a strong metal-support interaction (i.e., Ru and Ni sites) for individual catalysis in water splitting and is revealed to be termed as a real bifunctional electrocatalyst.