Li Zhe, Feng Yi, Liang Yu-Lin, Cheng Chuan-Qi, Dong Cun-Ku, Liu Hui, Du Xi-Wen
Institute of New-Energy Materials, School of Materials Science and Engineering, Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education, Tianjin University, Tianjin, 300072, China.
Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800, China.
Adv Mater. 2020 Jun;32(25):e1908521. doi: 10.1002/adma.201908521. Epub 2020 May 17.
Water electrolysis in alkaline electrolyte is an attractive way toward clean hydrogen energy via the hydrogen evolution reaction (HER), whereas the sluggish water dissociation impedes the following hydrogen evolution. Noble metal oxides possess promising capability for catalyzing water dissociation and hydrogen evolution; however, they are never utilized for the HER due to the instability under the reductive potential. Here it is shown that compressive strain can stabilize RhO clusters and promote their catalytic activity. To this end, a strawberry-like structure with RhO clusters embedded in the surface layer of Rh nanoparticles is engineered, in which the incompatibility between the oxide cluster and the metal substrate causes intensive compressive strain. As such, RhO clusters remain stable at a reduction potential up to -0.3 V versus reversible hydrogen electrode and present an alkaline HER activity superior to commercial Pt/C.
在碱性电解质中进行水电解是通过析氢反应（HER）获取清洁氢能的一种有吸引力的方法，然而缓慢的水离解过程阻碍了后续的析氢反应。贵金属氧化物具有催化水离解和析氢的潜在能力；然而，由于在还原电位下的不稳定性，它们从未被用于析氢反应。在此表明，压缩应变可以稳定RhO团簇并提高其催化活性。为此，设计了一种草莓状结构，其中RhO团簇嵌入Rh纳米颗粒的表层，氧化物团簇与金属基底之间的不相容性导致强烈的压缩应变。因此，RhO团簇在相对于可逆氢电极高达-0.3 V的还原电位下仍保持稳定，并表现出优于商业Pt/C的碱性析氢活性。
