A Nickel Coated Copper Substrate as a Hydrogen Evolution Catalyst
Poshan Kumar Reddy Kuppam, K.M.M.D.K. Kimbulapitiya, Srikanth Vuppala, Kuangye Wang, Phaneendra Reddy Guddeti, Krishna Pande, Po-Tsung Lee, Yun-Lun Chueh
Abstract
Replacing precious metals with low-cost metals is the best solution for large scale production. Copper is known for its excellent conductivity and thermal management applications. When it comes to hydrogen evolution reaction, it is highly unstable, especially in KOH solution. In this paper, we approached a simple method to reduce corrosion and improve the performance by depositing nickel-molybdenum oxide and nickel on copper substrates and the achieved tafel slopes of 115 mV/dec and 117 mV/dec at 10 mA/cm2. While at first, molybdenum oxide coated samples showed better performance after 100 cycles of stability tests, the onset potential rapidly changed. Cu-Ni, which was deposited using the electron gun evaporation (e-gun), has shown better performance with 0.28 V at 10 mA/cm2 and led to stability after 100 cycles. Our results show that when copper is alloyed with nickel, it acts as a promising hydrogen evolution reaction (HER) catalyst.