One-pot, large-scale, simple synthesis of CoxP nanocatalysts for electrochemical hydrogen evolution

Abstract

Non-noble metal based and earth-abundant electrocatalysts with high hydrogen evolution reaction (HER) activities are highly desirable as replacements for the scarce and expensive platinum-based catalysts. Cobalt phosphides (Co_xP) have been recently demonstrated as one of the most promising HER candidates in acidic electrolytes. However, the fabrication methods are normally tedious and produce only a small amount (few milligrams) of catalyst. In this paper, we report a one-pot, large-scale (tens of grams), simple synthesis of cobalt phosphide nanoparticles with impressive HER activities. The Co_xP catalyst, when obtained using suitable reaction conditions, shows a high cathodic current density at a low overpotential and a small Tafel slope (approximately 58 mV dec⁻¹). Thus, this study provides a practically promising approach to fabricate cost effective catalysts at a large scale for electrochemical hydrogen production.