Convex Cube-Shaped Pt34Fe5Ni20Cu31Mo9Ru High Entropy Alloy Catalysts toward High-Performance Multifunctional Electrocatalysis

作者：Chen, Zhaoqian; Wen, Jingbo; Wang, Chaohui; Kang, Xiongwu^*

来源：Small, 2022, 18(45): 2204255.

DOI：10.1002/smll.202204255

• convex cubes
• electrocatalysis
• high entropy alloys
• multifunction
• ruthenium

High entropy alloy (HEA) catalysts exhibit excellent multifunctional catalytic performance due to the synergistic effect of multi-metal components. However, shape-controlled synthesis of such kinds of HEA catalysts, especially those with high index facets, still faces great challenges, limiting further enhancement of their catalytic performance. Herein, one-pot synthesis of convex cube-shaped Pt34Fe5Ni20Cu31Mo9Ru HEA catalysts which possess rich (310) facets and a diagonal crystalline size of 38.5 nm is reported. Transmission electron microscopy measurements indicate cube-shaped nanocrystals are obtained first and further selective growth of pyramid on each facet of the cube-shaped nanocrystal results in a convex cube shape. Pt34Fe5Ni20Cu31Mo9Ru HEA catalysts show excellent electrocatalytic performance toward the oxygen reduction reaction (ORR), hydrogen evolution reaction (HER), and oxygen evolution reaction (OER), which exhibit a half-wave potential of 0.87 V for ORR in 0.1 m HClO4, and overpotential of 20 and 259 mV for HER and OER at a current density of 10 mA cm(-2) in an alkaline medium. A control experiment and density functional theory calculation indicate that the Ru element plays a decisive role in both the formation of the convex cube shape and also the high catalytic performance.