Investigation of a molybdenum atom-modified bifunctional electrocatalyst (Mo-NiFe LDH) with high-efficiency hydrogen evolution reaction performance

Abstract

Nickel iron layered double hydroxide (NiFe-LDH) has attracted extensive attention as a highly active OER catalyst in alkaline solutions due to its unique chemical and physical properties, as well as its low cost and high catalytic activity. However, its alkaline hydrogen evolution reaction activity is relatively low, resulting in poor overall water splitting performance. To address this issue, a highly efficient bifunctional electrocatalyst with a multi-dimensional porous structure composed of interlaced nanocrystalline sheets, 10%Mo-NiFe-LDH, was successfully synthesized in this work via electrodeposition. At a current density of 10 mA cm⁻², the overpotentials for the hydrogen evolution reaction and oxygen evolution reaction are as low as 97 mV and 229 mV, respectively, outperforming most metal-based catalysts. When used in overall water splitting, a voltage of only 1.55 V is required to achieve a current density of 10 mA cm⁻², and its performance remained the same after 24 hours of stability testing. This study systematically investigated the application of a molybdenum metal atom-modified multi-level bifunctional electrocatalyst (Mo-NiFe LDH) for efficient overall water splitting and hydrogen evolution during water electrolysis, providing important theoretical guidance and practical basis for achieving efficient alkaline hydrogen production and overall water splitting.