In situ growth of FeCo sulfides on cobalt iron foam for efficient high-current-density hydrogen evolution reaction electrocatalysis

J Colloid Interface Sci. 2024 Dec 1:682:288-297. doi: 10.1016/j.jcis.2024.11.251. Online ahead of print.

Abstract

Hydrogen, with its high energy density and environmental friendliness, represents an ideal alternative to traditional fossil fuels. The development of cost-effective electrocatalysts is crucial for achieving efficient hydrogen production through water splitting. In this study, a novel three-dimensional octahedral cubic Cu9S5-Cu7S4-CuS-Co9S8-Cu5FeS4/CFF (FeCoCuSx/CFF) electrocatalyst was synthesized via a facile two-step hydrothermal method using a unique Fe-Co alloy foam as the substrate. The catalyst demonstrated exceptional hydrogen evolution reaction (HER) performance, achieving an overpotential of only 272 mV at a high current density of 1000 mA cm-2 and maintaining stability for over 100 h at 100 mA cm-2. Theoretical calculations indicate that the Co sites in CuS-Co9S8 heterostructure exhibits the highest HER catalytic activity because of the GH* is near zero. These results indicate that the unique octahedral cubic architecture not only enriched heterogeneous structures but also facilitated gas adsorption, enhancing catalytic activity. This non-precious metal-based electrocatalyst, prepared through a hydrothermal approach, exhibits high catalytic activity and stability, showing promising potential for industrial applications in water electrolysis and as a viable alternative to precious metal-based electrocatalysts.

Keywords: Electrocatalysis; Hydrothermal; In-situ growth; Transition metal sulfide; Water electrolysis.