Probing the Irregular Lattice Strain-Induced Electronic Structure Variations on Late Transition Metals for Boosting the Electrocatalyst Activity

Owing to the simplicity in practice and continuous fine-tuning ability toward the binding strengths of adsorbates, the strain effect is intensively explored, especially focused on the modulation of catalytic activity in transition metal (TM) based electrocatalysts. Recently, more and more abnormal cases have been found that cannot be explained by the conventional simplified models. In this work, the strain effects in five late TMs, Fe, Co, Ni, Pd, and Pt are studied in-depth regarding the facet engineering, the surface atom density, and the d-band center. Interestingly, the irregular response of Fe lattice to the applied strain is identified, indicating the untapped potential of achieving the phase change by precise strain modulation. For the complicated high-index facets, the surface atom density has become the pivotal factor in determining the surface stability and electroactivity, which identifies the potential of high entropy alloys (HEA) in electrocatalysis. The work supplies insightful understanding and significant references for future research in subtle modulation of electroactivity based on the precise facet engineering in the more complex facets and morphologies. © 2020 Wiley-VCH GmbH.