Hydrogen oxidation reaction response of noble-metal based bulk metallic glasses
Hydrogen oxidation reaction response of noble-metal based bulk metallic glasses
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DOI：
10.1016/j.electacta.2020.136616
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发表时间：
2020-09
影响因子：
6.6
通讯作者：
V. Hasannaeimi;Chun-Yu Lin;Z. Xia;S. Mukherjee
中科院分区：
文献类型：
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作者：
V. Hasannaeimi;Chun-Yu Lin;Z. Xia;S. Mukherjee
贵金属基金属玻璃近年来在一系列催化反应中表现出优异的性能，这归功于其无序的原子结构和表面高密度的活性位点。深入了解促进非晶合金催化性能的机制将有助于设计和开发具有显著低贵金属负载的高效催化剂。采用循环伏安法和扫描电化学显微镜研究了非晶铂基和钯基金属玻璃对氢氧化反应的电催化行为。发现金属玻璃的电化学活性表面积比纯Pt和Pd高几倍。密度泛函理论计算表明，非晶合金表面的氢氧化优先遵循逆向的Heyrovsky-Volmer路径。与纯Pt和纯Pd相比，非晶合金的最小过电位明显降低，与实验趋势一致。非晶合金的催化活性增强是由于金属玻璃表面氢的化学吸附减少，特别是对于同时含有Pt和Pd的合金。
Noble-metal based metallic glasses have recently shown excellent performance towards a range of catalytic reactions, which is attributed to their disordered atomic structure and high density of active sites on the surface. An in-depth understanding of the mechanisms that promote the catalytic performance of amorphous alloys would facilitate the design and development of highly efficient catalysts with significantly lower precious metal loading. In the present study, the electro-catalytic behavior of amorphous Pt- and Pd-based metallic glasses was studied towards hydrogen oxidation reaction by cyclic voltammetry and scanning electrochemical microscopy. The electrochemically active surface area for the metallic glasses was found to be several folds higher compared to pure Pt and Pd. Density functional theory calculations showed that hydrogen oxidation on the surface of the amorphous alloys preferentially followed the reverse Heyrovsky-Volmer pathway. The minimum over-potential for the amorphous alloys was calculated to be significantly lower compared to pure Pt and Pd, consistent with the experimental trends. The enhanced catalytic activity for the amorphous alloys was attributed to the reduced chemisorption of hydrogen on the metallic glass surface, particularly for the alloys containing both Pt and Pd.