Characteristics of low-pressure-plasma-processed NiRu-MOFs/nickel foam for Hydrogen evolution reaction
Shuo-En Yu, Ying-Chyi Wang, Chia-Yun Tseng, I‐Chun Cheng, Jian‐Zhang Chen
Abstract
Abstract NiRu bimetallic metal–organic frameworks (NiRu-MOFs) are grown by a simple hydrothermal method on nickel foam (NF) as an the electrocatalyst for the hydrogen evolution reaction. Low-pressure plasmas of pure Ar, 95%Ar + 5%H 2 , and 95% Ar + 5%O 2 are used for the post-treatment of the NiRu-MOFs. NiRu-MOFs-AO with post-plasma treatment with 95%Ar + 5%O 2 show the lowest overpotential of 123.3 mV at a current density of 10 mA cm −2 and a Tafel slope of 72.0 mV dec −1 in 1 M KOH electrolyte. Electrochemical impedance spectroscopy results indicate that post-plasma treatment can further reduce the charge transfer resistance. Moreover, the electric double-layer capacitance (C dl ) is calculated based on the cyclic voltammetry results, and the electrocatalyst subjected to 95%Ar + 5%O 2 post-plasma treatment shows a 2C dl value of 3.69 mF/cm 2 , suggesting a larger electrochemically active surface area after oxygen-containing-plasma treatment.