Modulation and engineering of MOF-derived transition metal selenides/NiFe LDH for application in electrocatalytic hydrogen evolution

Abstract

Alkaline electrolysis represents a commercially viable technology for the eco-friendly production of high-purity hydrogen. Metal–organic frameworks (MOFs), with their abundant morphology, tunable electronic structure, and stability, are frequently employed as precursors for electrocatalysts. In this study, a heterogeneous triangular column array was in situ constructed on nickel foam (NF) by coupling metal–organic framework (MOF) derived Ni–Co–Se with NiFe layered double hydroxides (LDHs) through hydrothermal and electrodeposition methods. The electrocatalytic performance of the bifunctional catalyst during the water splitting reaction was systematically investigated. The unique design of this hybrid catalyst in terms of electronic engineering and morphology regulation facilitated the generation and exposure of numerous active sites, enhanced the permeability of the electrolyte, and promoted the release of gases during the reaction, all of which are crucial for improving reaction efficiency. The resulting composite electrode of Ni–Co–Se@NiFe LDH demonstrates superior performance in the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), delivering a current density of 10 mA cm⁻² at an overpotential of 78 mV for the HER and 234 mV@50 mA cm⁻² for the OER. Notably, the Ni–Co–Se@NiFe LDH catalyst also displays outstanding overall water-splitting activity, requiring only a low cell voltage of 1.52 V to provide a current density of 10 mA cm⁻², outperforming the noble metal catalyst RuO₂/NF‖Pt–C/NF (1.60 V@10 mA cm⁻²). This research presents a feasible strategy for the advancement and application of bifunctional electrocatalysts for overall water splitting.