Screening Highly Efficient Hetero-Diatomic Doped PC6 Electrocatalysts for Selective Nitrogen Reduction to Ammonia

Abstract

Searching for highly efficient electrocatalysts toward nitrogen reduction reaction (NRR) is an important but challenging task for nitrogen utilization in industry. Here we have systematically designed a series of hetero-diatomic catalysts (DACs), in which transition metal atoms (Ti, V, Cr, Mn, Fe, Co, and Ni) are dispersed on PC 6 monolayer to form AB@PC 6 (A, B = Ti, V, Cr, Mn, Fe, Co, and Ni). Employing density functional theory (DFT) calculation, the V and Cr co-doped PC 6 monolayer (VCr@PC 6 ) among the 21 AB@PC 6 catalysts is the most promising catalyst due to its low limiting potential of −0.41 V, relatively low energy barrier, and high ammonia selectivity toward hydrogen evolution reaction (HER). Insights on the high NRR activity of VCr@PC 6 are also explored. The synergistic effect in DACs facilitates the electron transfer from metal pairs to PC 6 monolayer, as well as suppresses the HER, leading to high selectivity and Faradaic efficiency. This work not only aims to seek the efficient DACs towards N 2 reduction but also provides insights towards synergistic effects between hetero-atoms for the rational design of DACs.