Coupling porous Ni doped LaFeO3 nanoparticles with amorphous FeOOH nanosheets yields an interfacial electrocatalyst for electrocatalytic oxygen evolution

Abstract

Perovskite oxides (ABO₃) with flexible structural and chemical properties have attracted wide attention in electrocatalytic water splitting. However, their poor intrinsic activity and unsuitable adsorption energy for oxygenated species greatly limit their application. Heteroatom doping has been demonstrated to be an efficient strategy to modulate the electronic structure of the host and thus improve its OER properties. And FeOOH can effectively adsorb OER intermediates and provide abundant active sites for the OER. Herein, a novel hybrid OER electrocatalyst consisting of Ni-doped LaFeO₃ with a porous structure combined with ultra-thin amorphous FeOOH nanosheets (NiFe–LFO) is successfully designed and prepared via a simple two-step hydrothermal method. The prepared catalyst exhibited an extremely low overpotential of 186 mV at 10 mA cm⁻². Density functional theory calculations reveal that the strong electronic interactions at the interface of the composite play a crucial role in the enhancement of catalytic performance. And the Ni²⁺ doping effectively modulates the electronic structure of LFO and enhances the electron transport at the interface of LFO and FeOOH, resulting in an elevated d-band centre of FeOOH, thus leading to high OER activity. This work provides an approach for designing other advanced OER electrocatalysts for sustainable energy devices.