Real-time dynamic simulation of laser-induced N2 dissociation on two-dimensional graphene sheets.

Due to its relatively high inertness, nitrogen dissociation at ambient temperature and pressure has always been a challenging task. Plasmon driven photocatalysis has proved to be an effective method. Owing to their unique physical, chemical, and electronic properties, two-dimensional planar materials have become the most promising candidates to replace noble metal catalytic nitrogen reduction. In this study, real-time dynamics of N2 dissociation on graphene sheets under femtosecond laser irradiation was studied by using time-dependent density functional theory. We confirm that electrons generated by plasmon excitation of graphene transfer to the N2 molecular antibonding orbital and activate the N-N bond. The threshold of laser intensity of N2 dissociation can be effectively reduced by mixing CO molecules. This work provides basic insights for understanding the plasmon induced N2 activation process at the atomic scale and proves that graphene can be used as one of the candidate materials for N2 reduction photocatalysts with excellent performance.