Surface defect-abundant one-dimensional graphitic carbon nitride nanorods boost photocatalytic nitrogen fixation

Abstract

The synthesis of ammonia via the Haber–Bosch process requires high temperature and high pressure, which causes about 1.6% of global CO₂ emission every year. the development of a low-cost, facile ammonia synthesis method under ambient conditions is urgently required. Herein, we employed a facile approach to prepare defective g-C₃N₄ nanorods with a narrower bandgap and a sub-gap, which can significantly enhance the light utilization ratio. More importantly, the defects of g-C₃N₄ nanorods can also enhance the light adsorption and boost cleavage of N₂ molecules, which is the rate-determining step of nitrogen fixation. Compared with bulk g-C₃N₄, the photocatalytic N₂ reduction rate of defective g-C₃N₄ nanorods as the catalysts was increased by 3.66 times. According to the density functional theory calculation results, the active sites should be an extra carbon in the ring formed in s-triazine rings. This work may provide in-depth insights into the development of novel defective photocatalysts for N₂ fixation.