Computational design of one FeCoNiCuZn high-entropy alloy for high-performance electrocatalytic nitrate reduction

The electrocatalytic nitrate reduction to ammonia (eNRA) is a promising solution for addressing nitrate pollution while also enabling efficient ammonia synthesis and resource utilization. In this study, we employ a combination of first-principle density functional theory (DFT) calculation and Monte Carlo simulation to investigate the feasibility of eNRA on different crystal planes of FeCoNiCuZn high-entropy alloy (HEA). Our computational results demonstrate that the (1 0 0) crystal plane of FeCoNiCuZn HEA exhibits excellent catalytic activity for eNRA, characterized by an ultra-low overpotential of 0.22 V and a kinetical barrier of 0.954 eV. Moreover, the HEA also demonstrates exceptional selectivity (99.9 %), which suppresses secondary reactions (HER). Through a thorough analysis of the electronic structure, we identify that the electrocatalytic activity of HEA is primarily attributed to the position of the d-band center. This work not only presents a high-performance electrocatalyst candidate for eNRA but also expands the research scope of HEAs.