Insights into electrocatalytic hydrogen evolution reaction in acidic medium at in-situ dispersed Pt atoms on nanoporous gold films
Insights into electrocatalytic hydrogen evolution reaction in acidic medium at in-situ dispersed Pt atoms on nanoporous gold films
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DOI：
10.1016/j.jcat.2018.10.026
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发表时间：
2018-12
影响因子：
7.3
通讯作者：
Ruike Guo;Xiaoxing Xu;Yue Xia;Wei Huang;Zelin Li;Botao Teng
中科院分区：
文献类型：
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作者：
Ruike Guo;Xiaoxing Xu;Yue Xia;Wei Huang;Zelin Li;Botao Teng
高分散铂原子在纳米多孔表面上的电催化析氢反应具有重要的理论和实践意义。本工作首次采用循环伏安法在纳米多孔金膜上原位分散了微量Pt（NPGF-t-Pt）。它涉及在循环伏安法期间在表面处的Au和Pt原子的同时氧化还原和合金化。在原位优化的0.5at%的临界Pt含量下，NPGF-t-Pt电极具有与具有几乎相同的表面粗糙度的纳米多孔Pt表面几乎相同的HER几何电流密度。非原位合金化纳米Au_（95）Pt_（55）电极的铂质量HER电流密度约为纳米Pt电极的20倍。基于实验结果提出了一个包含7个表面基元反应步骤的改进的HER机理，并得到了密度泛函理论计算的支持。它给出了一个更深入的洞察HER在分散的Pt原子（约5at%）的NPGF表面上。我们希望这项工作将促进电催化HER在分散的活性原子的临界含量。
Electrocatalytic hydrogen evolution reaction (HER) at highly dispersed Pt atoms on nanoporous surfaces is of significance both in practice and in theory. In this work, in situ surface dispersion of tiny amount of Pt (NPGF-t-Pt) on a nanoporous gold film for HER has been carried out by repeated cyclic voltammetry for the first time. It involves simultaneous redox and alloying of Au and Pt atoms at the surface during the cyclic voltammetry. At a critical Pt content of ∼5 at% that is in situ optimized, the NPGF-t-Pt electrode has nearly the same HER geometrical current density as the nanoporous Pt surface with almost the same surface roughness. The Pt-mass HER current density on the ex situ alloyed nano-Au95Pt5electrode is about 20 times that on the nano-Pt electrode. A modified HER mechanism containing seven surface elementary reaction steps has been proposed based on the experimental results, which is also supported by density functional theoretical calculation. It gives a deeper insight into the HER at the dispersed Pt atoms (∼5 at%) on the NPGF surface. We expect that this work will promote the electrocatalytic HER at dispersed active atoms with a critical content.