Density functional theory study of N2 adsorption and dissociation on 3d transition metal atoms doped Ir(100) surface

Ammonia is among the chemicals that are produced in large amounts worldwide and therefore play an important role in global economy. Recently, the electrocatalytic nitrogen reduction reaction (NRR) has attracted significant research attention as the most promising technology for ammonia synthesis. Therefore, designing an efficient electrocatalyst is a crucial issue that needs to be addressed. In this study, using density functional theory calculations, we designed a series of electrocatalysts containing 3d transition metal (TM = Ti-Zn) atoms doped on Ir (100) surface (TM@Ir(100)) and studied the effect of TM@Ir(100) on N-2 adsorption, activation, and dissociation. The doping of TM atoms regulated the electronic structure of Ir(100) and promoted its catalytic activity. TM@Ir(100) (TM = Ti, V, Cr, Mn, Fe, and Co) effectively activated N-2, and the N-N bond was elongated to similar to 1.290 angstrom. The doping of TM atoms promoted charge transfer between N-2 and TM@Ir(100) and activated the N=N bond, affording high catalytic activity. Furthermore, the dissociation behavior of N-2 on TM@Ir(100) was investigated. Mn@Ir(100) exhibited the highest catalytic activity and a low energy barrier for N-2 dissociation (0.598 eV), making it a potential NRR electrocatalyst.