Correlation of the spin state and catalytic property of M-N single-atom catalysts in oxygen reduction reactions.

The rational design of high-performance catalysts for oxygen reduction reactions (ORRs) is of great importance for large-scale applications in the field of proton-exchange membrane fuel cells and the green synthesis of HO. The effect of spin states of paramagnetic metal ions on the selectivity of ORRs is significant for single-atom catalysts (SACs). In this work, spin-polarization density functional theory (DFT) calculations, we systematically investigated the popular paramagnetic metal-nitrogen graphene (M-N-C, M = Mn, Fe, and Co) SACs to mainly focus on the correlation of spin states and catalytic performance ( activity and selectivity).

Dual effect of the coordination field and sulphuric acid on the properties of a single-atom catalyst in the electrosynthesis of HO.

Electrocatalytic synthesis of hydrogen peroxide (HO) the two-electron oxygen reduction reaction (2e ORR) is the ideal solution for on-site HO production. Herein, we propose a new strategy for creating new 2e ORR catalysts by introducing electron-deficient B atoms and electron-rich N atoms to regulate the coordination field of metal ions on a graphene substrate. Through the first-principles density functional theory (DFT) calculations, NiNB-h was screened out as it had a low overpotential (0.

High-performance single-atom Ni catalyst loaded graphyne for HO green synthesis in aqueous media.

The electrochemical synthesis of hydrogen peroxide (HO) provides a greener and more efficient method compared with classic catalysts containing toxic metals. Herein, we used first-principles density functional theory (DFT) calculations to investigate 174 different single-atom catalysts with graphyne substrates, and conducted a three-step screening strategy to identify the optimal noble metal-free single atom catalyst. It is found that a single Ni atom loaded on γ-graphyne with carbon vacancies (Ni@V-γ-GY) displayed remarkable thermodynamic stability, excellent selectivity, and high activity with an ultralow overpotential of 0.