Zhao Di, Jia Pengcheng, Li Ling, Tang Yang, Cui Qiuhong, Zhan Chuanlang, Hou Yanbing, Hu Yufeng, Lou Zhidong, Teng Feng
Key Laboratory of Luminescence and Optical Information, Ministry of Education, Beijing Jiaotong University Beijing 100044 China
Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences Beijing 100190 China
RSC Adv. 2020 Dec 9;10(71):43508-43513. doi: 10.1039/d0ra08090j. eCollection 2020 Nov 27.
The use of ternary polymer solar cells (PSCs) is a promising strategy to enhance photovoltaic performance while improving the fill factor (FF) of a device, but is still a challenge due to the complicated morphology. Herein, ternary PSCs are fabricated adding the conjugated small molecule -DTS(FBTTh) into a well-known blended film, PTB7-Th:IEICO-4F. The ternary blend morphology and device characterization reveal that the addition of -DTS(FBTTh) can improve crystallinity and optimize morphology, leading to the FF of the optimized device increasing to 73.69%. In combination with the advantages of an ultra-narrow bandgap material, IEICO-4F, with a broad optical absorption spectrum, the optimized ternary solar cell exhibits a high short-circuit current-density ( ) of 25.22 mA cm. The best power conversion efficiency (PCE) is 12.84% for this optimized ternary device with 10 wt% -DTS(FBTTh) in the donors. This work indicates that incorporating a small molecule with high crystallinity into host binary non-fullerene PSCs would give an active layer with high crystallinity, thus greatly enhancing the FFs and PCEs of PSCs.
使用三元聚合物太阳能电池（PSC）是一种很有前景的策略，可在提高器件填充因子（FF）的同时增强光伏性能，但由于其复杂的形态，这仍然是一个挑战。在此，通过将共轭小分子-DTS(FBTTh)添加到著名的混合薄膜PTB7-Th:IEICO-4F中来制备三元PSC。三元混合形态和器件表征表明，添加-DTS(FBTTh)可以提高结晶度并优化形态，从而使优化器件的FF提高到73.69%。结合具有宽光学吸收光谱的超窄带隙材料IEICO-4F的优点，优化后的三元太阳能电池表现出25.22 mA cm的高短路电流密度（ ）。对于在供体中含有10 wt%-DTS(FBTTh)的这种优化三元器件，最佳功率转换效率（PCE）为12.84%。这项工作表明，将具有高结晶度的小分子掺入主体二元非富勒烯PSC中会得到具有高结晶度的活性层，从而极大地提高PSC的FF和PCE。
