Tailoring Mott−Schottky RuO2/MgFe‐LDH Heterojunctions in Electrospun Microfibers: A Bifunctional Electrocatalyst for Water Electrolysis

Abstract Hydrogen is a fuel of the future that has the potential to replace conventional fossil fuels in several applications. The quickest and most effective method of producing pure hydrogen with no carbon emissions is water electrolysis. Developing highly active electrocatalysts is crucial due to the slow kinetics of oxygen and hydrogen evolution, which limit the usage of precious metals in water splitting. Interfacial engineering of heterostructures has sparked widespread interest in improving charge transfer efficiency and optimizing adsorption/desorption energetics. The emergence of a built‐in‐electric field between RuO 2 and MgFe‐LDH improves the catalytic efficiency toward water splitting reaction. However, LDH‐based materials suffer from poor conductivity, necessitating the design of 1D materials by integration of RuO 2 / MgFe‐LDH to enhance catalytic properties through large surface areas and high electronic conductivity. Experimental results demonstrate lower overpotentials (273 and 122 mV at 10 mA cm −2 ) and remarkable stability (60 h) for the RuO 2 /MgFe‐LDH/Fiber heterostructure in OER (1 m KOH) and HER (0.5 m H 2 SO 4 ) reactions. Density functional theory (DFT) unveils a synergistic mechanism at the RuO 2 /MgFe‐LDH interface, leading to enhanced catalytic activity in OER and improved adsorption energy for hydrogen atoms, thereby facilitating HER catalysis.