Affiliation:
1. College of Physics and Electronic Information, Inner Mongolia Normal University, Hohhot 010022, China
2. Inner Mongolia Key Laboratory for Physics and Chemistry of Functional Materials, Hohhot 010022, China
Abstract
Exploring highly active electrocatalysts as platinum (Pt) substitutes for the oxygen reduction reaction (ORR) remains a significant challenge. In this work, single Mn embedded nitrogen-doped graphene (MnN4) with and without halogen ligands (F, Cl, Br, and I) modifying were systematically investigated by density functional theory (DFT) calculations. The calculated results indicated that these ligands can transform the dyz and dxz orbitals of Mn atom in MnN4 near the Fermi-level into dz2 orbital, and shift the d-band center away from the Fermi-level to reduce the adsorption capacity for reaction intermediates, thus enhancing the ORR catalytic activity of MnN4. Notably, Br and I modified MnN4 respectively with the lowest overpotentials of 0.41 and 0.39 V, possess superior ORR catalytic activity. This work is helpful for comprehensively understanding the ligand modification mechanism of single-atom catalysts and develops highly active ORR electrocatalysts.
Funder
Natural Science Foundation of Inner Mongolia Autonomous Region
Research Program of Science and Technology at Universities of Inner Mongolia Autonomous Region
Fundamental Research Funds for the Inner Mongolia Normal University
Innovation and Entrepreneurship Training Program for College Students at Inner Mongolia Normal University