Crystal Phase Transition Creates a Highly Active and Stable RuCX Nanosurface for Hydrogen Evolution Reaction in Alkaline Media

• DOI: 10.1002/adma.202105248
• Publication Date: 2021-10-08T05:07:35Z
• Authors: Jeonghyeon Kim; Hee Jin Kim; Bibi Ruqia; Mi Ji Kim; Yeong‐Ji Jang; Tae Hwan Jo; Hionsuck Baik; Hyung‐Suk Oh; Hee‐Suk Chung; Kangkyun Baek; Siwoo Noh; Moonjung Jung; Ki‐jeong Kim; Hyung‐Kyu Lim; Young‐Sang Youn; Sang‐Il Choi
• Keywords: Overpotential; Metastability; Crystal (programming language)

Abstract Although metastable crystal structures have received much attention owing to their utilization in various fields, phase‐transition a thermodynamic structure has attracted comparably little interest. In the case of nanoscale crystals, such an exothermic releases high energy within confined surface area and reconstructs atomic arrangement short time. Thus, this high‐energy nanosurface may create novel when some elements are supplied. work, creation ruthenium carbide (RuC X , < 1) phase on Ru nanocrystal is discovered during from cubic‐close‐packed hexagonal‐close‐packed structure. When electrocatalytic hydrogen evolution reaction (HER) tested alkaline media, RuC exhibits lower overpotential good stability relative counterpart Ru‐based catalysts state‐of‐the‐art Pt/C catalyst. Density functional theory calculations predict that local heterogeneity outermost promotes bifunctional HER mechanism by providing catalytic sites for both H adsorption facile water dissociation.