All-Small-Molecule Organic Solar Cells Based on a Fluorinated Small Molecule Donor With High Open-Circuit Voltage of 1.07 V

Liu, CY (Liu, Chunyan)^{[ 1 ]} ; Qiu, NL (Qiu, Nailiang)^{[ 1 ]} ; Sun, YN (Sun, Yanna)^{[ 2,3 ]} ; Ke, X (Ke, Xin)^{[ 2,3 ]} ; Zhang, HT (Zhang, Hongtao)^{[ 2,3 ]} ; Li, CX (Li, Chenxi)^{[ 2,3 ]} ; Wan, XJ (Wan, Xiangjian)^{[ 2,3 ]} ; Chen, YS (Chen, Yongsheng)^{[ 2,3 ]}

FRONTIERS IN CHEMISTRY, 2020, 8: 文献号: 329

DOI: 10.3389/fchem.2020.00329

摘要

A new small molecule donor with an acceptor-donor-acceptor (A-D-A) structure, namely DRTB-FT, has been designed and synthesized for all-small-molecule organic solar cells (ASM-OSCs). By introducing fluorine atoms on the thienyl substituent of the central benzodithiophene unit, DRTB-FT shows a low-lying highest occupied molecular orbital (HOMO) energy level of -5.64 eV. Blending with an A-D-A type acceptor F-2Cl, DRTB-FT based ASM-OSCs gave a power conversion efficiency (PCE) of 7.66% with a high open-circuit voltage (V-oc) of 1.070 V and a low energy loss of 0.47 eV. The results indicate that high V-oc of ASM-OSC devices can be obtained through careful donor molecular optimization.