▎ 摘　　要

Doping with heteroatoms is an effective way to modify the electronic structures and photophysical properties of graphene quantum dots (GQDs). However, there are few studies on phosphorus-doped GQDs (P-GQDs), espe-cially with respect to the dynamics of electron-hole recombination, which plays a crucial role in the energy conversion performance of P-GQDs. In the current study, we investigate the effect of phosphorus-containing groups (i.e., phosphine oxide, phosphonic acid, phosphate, and phosphinic acid) on the electronic structures, optical properties, and dynamics of nonradiative recombination of P-GQDs with different edge coverages and structural symmetries. Our results show that P-doping disrupts the integrity of the conjugated pi-skeleton of carbon system, leading to the localization of electrons in P-GQDs. The phosphine oxide has a stronger effect on the sp2 bonding environment of the carbon skeleton, leading to a greater impact on the geometrical and elec-tronic structures of the P-GQDs than in the other P-functionalized systems. The increase in the passivation density of phosphinic acid leads to localization of electron and hole densities at the periphery of the GQDs. In addition, the P-C bond in phosphonic acid dramatically increases the electronic coupling, leading to the fastest non-radiative decay rate. The overall photovoltaic performance of phosphate-and phosphine oxide-functionalized GQDs are better than the other P-functionalized GQDs. Our calculations provide guidance for the rational design of P-doping configurations in P-GQDs to improve their energy conversion efficiency.