▎ 摘　　要

In situ-derived boron-doped graphene quantum dots can significantly improve the activity of boron carbide nanosheets for artificial N-2 fixation and reduction with superior electrocatalytic activity (NH3 yield: 28.6 mu g h(-1) mg(cat.)(-1) at -0.45 V vs. RHE; faradaic efficiency: 16.7%), high electrochemical stability, and high selectivity in 0.1 M HCl under ambient conditions.