Ruthenium single atoms implanted on NiS2-FeS2 nanosheet heterostructures for efficacious water electrolysis

Abstract

The catalytic potential of single atom incorporated heterostructures holds substantial promise because of their ability to offer customizable chemical functionality and abundant active sites. In this study, a novel approach is employed to synthesize ruthenium single atoms (Ru_SA) implanted on bimetallic NiFe-LDH derived sulfide nanosheet heterostructures (Ru_SA-NiS₂-FeS₂) via a facile technique. Experimental findings demonstrate that Ru_SA-NiS₂-FeS₂ exhibits lower overpotential (η) for water splitting. Specifically, the hydrogen evolution reaction (HER) overpotentials at current densities of (10 and 100) mA cm⁻² are measured to be (57 and 187) mV, respectively. Similarly, at (20 and 100) mA cm⁻², the oxygen evolution reaction (OER) overpotentials are recorded to be (242 and 304) mV, respectively. Conspicuously, the Ru_SA-NiS₂-FeS₂ (+, −) electrolyzer requires cell potentials of (1.47 and 1.74) V at (10 and 100) mA cm⁻², lower than the cell potentials of (1.57 and 1.92) V required by the RuO₂@NF (+)//Pt–C@NF (−) device to achieve similar current densities. These experimental results and the Density Functional Theory (DFT) calculations unveil that our research offers a promising method for single atom implanted heterostructures that can be used for large-scale clean hydrogen production through water electrolysis.