| 초록 |
Molecular doping has recently become an interesting topic for tuning the electronic properties of active layers in the field of organic solar cells. Herein, we introduced bis(pentafluorophenyl)zinc (BPFZn) as a dopant to the organic solar cells involving poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b’]dithiophene-co-3-fluorothieno[3,4-b]thiophene-2-carboxylate] (PTB7-Th) as a p-type and phenyl-C71-butyric acid methyl ester (PC70BM) as an n-type components. We found that BPFZn was beneficial for charge transport and transfer, in which the photogenerated excitons could be dissociated into free charges. A photoluminescence measurement revealed stronger quenching effect by 0.01 wt% BPFZn doping, implying a more efficient charge transfer. Besides, the external quantum efficiency increased from 63% to 66%, indicating an effective photon-to-electron conversion. As a result,, the efficiency increased from 7.67% to 8.69% in the pristine and doped solar cells, respectively. |
