Scalable Plasma-Processed NiMo Electrocatalysts for Efficient Hydrogen Evolution: Enhancement of Catalytic Efficiency through Plasma Surface Modification

Abstract

Given the rising global energy demands and environmental concerns, developing efficient, non-hazardous methods for producing electrocatalysts is crucial. The challenge lies not only in enhancing catalyst performance but also in finding scalable, cost-effective techniques for large-scale production. Plasma technologies, with their adaptability and versatility in energy conversion and storage, have garnered significant attention. These chemical-free methods provide precise control over material properties and enable the fabrication of high-performance electrocatalysts in a single step. In this work, plasma technology is leveraged to fabricate a durable, high-performance NiMo electrocatalyst in varying ratios (3:1, 3:2, 3:3) for the hydrogen evolution reaction (HER) using atmospheric plasma spray. The NiMo(3:3) composition demonstrates superior catalytic performance with an overpotential of 112 mV at a current density of 20 mA cm⁻². Further, Low-pressure nitrogen plasma treatment for 15 minutes significantly reduces the overpotential to 78 mV, enhancing HER performance by altering surface properties and boosting active site exposure. The catalyst also shows a lower Tafel value of 57.16 mV dec⁻¹ and high stability in chronoamperometry under acidic conditions for 30 hours, proving its sustainability in harsh environments. This work provides solid evidence of plasma's suitability as a powerful and sustainable approach for fabricating advanced electrocatalysts in energy applications