Adsorption energy as a promising single-parameter descriptor for single atom catalysis in the oxygen evolution reaction

Abstract

Rationalizing a single-parameter descriptor that can conveniently and accurately evaluate the catalytic performance of single-atom catalysts (SACs) for the oxygen evolution reaction (OER) is one of the most important and challenging goals in electrochemical energy applications. Herein, the OER processes for different SACs based on various mono-layer materials, such as transition-metal dichalcogenide (TMDs) and group-III monochalcogenide mono-layers, have been systematically investigated, based on which we demonstrate that the adsorption energy (E_ad) of transition-metal (TM) atoms can serve as a promising single-parameter descriptor in conveniently and efficiently predicting the catalytic performance of SACs for the OER. A favorable linear relationship between E_ad and adsorption free energy of reaction intermediates as well as the overpotential of the OER was evidenced. The reliability of the proposed descriptor was verified using nearly 100 samples together with the consistent results compared with the available experimental data. More importantly, such a single-parameter descriptor, E_ad, can be obtained directly from the initial optimized structures, offering a simple and efficient strategy for evaluating the performance of SACs. Thus, this highlighted descriptor without the need for considering the complicated reaction process can not only reduce the computational cost but also assist in designing non-noble SACs to substitute experimentally identified Ru/Ir-based catalysts.