The Hierarchical Trimetallic FeCoNi LTH/MnMoO ₄ /GO Nanohybrid as an Active Catalyst with Enhanced Bifunctional Performance for Efficient Overall Water Splitting

High Resolution Image Download MS PowerPoint Slide The development of efficient and stable bifunctional electrocatalysts based on Earth-abundant elements for sustainable hydrogen production via water splitting is of significant importance. In this study, we present the design and synthesis of a novel and highly efficient electrode based on trimetallic FeCoNi layered triple hydroxide (LTH) nanoparticles decorated over MnMoO 4 nanorods and graphene oxide (GO) electrodeposited onto fluorine-doped tin oxide (FTO) substrates. The heterostructured interface among the FeCoNi LTH nanoparticles, MnMoO 4 nanorods, and GO also offers more available catalytic sites, enhances electronic interactions, and accelerates the kinetics of water dissociation. As a result, the FeCoNi LTH/MnMoO 4 /GO/FTO electrocatalyst shows improved bifunctional electrocatalytic activity toward both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), delivering a low overpotential of 238 mV for the OER and 92 mV for the HER at a current density of ±10 mA cm –2, along with small Tafel slopes of 53 and 46 mV dec –1, respectively. Furthermore, the electrocatalyst preserves outstanding stability over 31 h of continuous electrolysis with an overall water-splitting voltage of 1.57 V at 10 mA cm –2, surpassing the performance of commercial RuO 2 -based systems. This work presents a novel method for constructing high-performance and bifunctional electrocatalysts based on Earth-abundant elements for efficient water electrolysis, offering a promising pathway toward cost-effective large-scale hydrogen production.