Ultra-small Cu-Ni nanoalloy as a high-performance supercapacitor electrode material and highly durable methanol oxidation electrocatalyst

Ultra-small, pristine nanoalloy particles have attracted considerable attention for applications ranging from electrocatalysis to electrochemical energy storage owing to their high conductivity and large specific surface area. However, their practical deployment relies on a controllable process is low-cost, scalable, and results in numerous monodispersed particles. In this work, we demonstrate an alcohothermal process that is scalable to obtain ultra-small (r < 4 nm) and monodispersed (similar to 4.1 +/- 0.5 nm) Cu-Ni nanoalloy particles. Ethylene-glycol was used as a reaction medium that also acts as an in situ reducing and capping agent responsible for nanoalloy formation. The prepared nanoalloy particles were electrochemically tested for supercapacitor and methanol-oxidation applications. The nanoalloy electrode showed a desirable specific capacitance of 858F g(-1) at a current density of 1 Ag-1 with good cyclic stability. As a catalyst for methanol-oxidation, the nanoalloy showed a high current density of similar to 191.5 mA cm(-2). The methanol-oxidation reaction current reached 156 mA while maintaining 83% of its initial value, even after 300 cycles. The observed superior electrochemical performance is attributed to the high conductivity, fast electron transport, and large specific surface associated with ultra-small Cu-Ni nanoalloy particles. (C) 2021 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.

Automated summary

This study demonstrates a scalable alcohothermal process to obtain ultra-small and monodispersed Cu-Ni nanoalloy particles, showing excellent electrochemical performance for supercapacitor and methanol oxidation applications. The high conductivity, fast electron transport, and large specific surface area of the ultra-small nanoalloy particles contribute to their superior electrochemical properties.