Single Metal-Embedded Nitrogen Heterocycle Aromatic Catalysts for Efficient and Selective Two-Electron Water Electrolysis Toward Hydrogen Peroxide

Abstract

Hydrogen peroxide (H₂O₂) is an eco-friendly chemical with widespread industrial applications. However, the commercial anthraquinone process for H₂O₂ production is energy-intensive and environmentally harmful, highlighting the need for more sustainable alternatives. The electrochemical production of H₂O₂ via the two-electron water oxidation reaction (2e⁻ WOR) presents a promising route but is often hindered by low efficiency and selectivity, due to the competition with the oxygen evolution reaction. In this study, we employed high-throughput computational screening and microkinetic modeling to design a series of efficient 2e⁻ WOR electrocatalysts from a library of 240 single-metal-embedded nitrogen heterocycle aromatic molecules (M-NHAMs). These catalysts, primarily comprising post-transition metals, such as Cu, Ni, Zn, and Pd, exhibit high activity for H₂O₂ conversion with a limiting potential approaching the optimal value of 1.76 V. Additionally, they exhibit excellent selectivity, with Faradaic efficiencies exceeding 80% at overpotentials below 300 mV. Structure-performance analysis reveals that the d-band center and magnetic moment of the metal center correlated strongly with the oxygen adsorption free energy (${∆G}_{O^{*}}$), suggesting these parameters as key catalytic descriptors for efficient screening and performance optimization. This study contributes to the rational design of highly efficient and selective electrocatalysts for electrochemical production of H₂O₂, offering a sustainable solution for green energy and industrial applications.