▎ 摘　　要

The effect of incorporating graphene quantum dots (GQDs) synthesized by a hydrothermal method in the active layer of organic solar cells was investigated. The doping of GQDs into poly[N-9 ''-hepta-decanyl-2,7-carbazole-alt-5,5-(4',7-di-2-thienyl-2',1',3'-benzothiadiazole)]:C-71-butyric acid methyl ester (PCDTBT:PC71BM) active layer resulted in 21% enhancement in power conversion efficiency. The doped GQDs act as exciton dissociation centres in the PCDTBT:PC71BM system. The improvement can be mainly attributed to the fact that the GQDs provide plenty of exciton dissociation interfaces and improve the charge transport pathway. Moreover, the doping of GQDs also offered a general route to optimize the light absorption of organic photovoltaic devices. Our results indicate that doping of hydrothermally synthesized GQDs offers a facile approach to improve the performance of the polymer solar cells.