Affiliation: | 1. State Key Laboratory of Organic–Inorganic Composites, Beijing Key Laboratory of Energy Environmental Catalysis, Beijing University of Chemical Technology, Beijing, 100029 P. R. China GRINM Group Corporation Limited, Beijing, 100088 P. R. China Grirem Advanced Materials Co., Ltd., Beijing, 100088 P. R. China Hebei Province Rare Earth Functional Materials Manufacturing, Innovation Center, Xiongan, 071700 P. R. China These authors contributed equally to this work.;2. State Key Laboratory of Organic–Inorganic Composites, Beijing Key Laboratory of Energy Environmental Catalysis, Beijing University of Chemical Technology, Beijing, 100029 P. R. China These authors contributed equally to this work.;3. GRINM Group Corporation Limited, Beijing, 100088 P. R. China;4. GRINM Group Corporation Limited, Beijing, 100088 P. R. China Grirem Advanced Materials Co., Ltd., Beijing, 100088 P. R. China Hebei Province Rare Earth Functional Materials Manufacturing, Innovation Center, Xiongan, 071700 P. R. China;5. State Key Laboratory of Organic–Inorganic Composites, Beijing Key Laboratory of Energy Environmental Catalysis, Beijing University of Chemical Technology, Beijing, 100029 P. R. China |
Abstract: | Co-based nanoalloys show potential applications as nanocatalysts for the oxygen reduction reaction (ORR), but improving their activity is still a great challenge. In this paper, a strategy is proposed to design efficient Co-M (M=Au, Ag, Pd, Pt, Ir, and Rh) nanoalloys as ORR catalysts by using density functional theory (DFT) calculations. Through the Sabatier analysis, the overpotential as a function of ΔGOH* is identified as a quantitative descriptor for analyzing the effect of dopants and atomic structures on the activity of the Co-based nanoalloys. By adopting the suitable dopants and atomic structures, ΔGOH* accompanied by overpotential could be adjusted to the optimal range to enhance the activity of the Co-based nanoalloys. With this strategy, the core–shell structured Ag42Co13 nanoalloy is predicted to have the highest catalytic activity for ORR among these Co-based nanoalloys. To give a deeper insight into the properties of Ag-Co nanoalloys, the structure, thermal stability, and reaction mechanism of Ag-Co nanoalloys with different compositions are also studied by using molecular simulations and DFT calculations. It is found that core–shell Ag42Co13 exhibits the highest structural and thermal stability among these Ag-Co nanoalloys. In addition, the core–shell Ag42Co13 shows the lowest ORR reaction energy barriers among these Ag-Co nanoalloys. It is expected that this kind of strategy could provide a viable way to design highly efficient heterogeneous catalysts in extensive applications. |