In this work, through adding an iridium complex material, (tfmppy)2Ir(tpip), in the active layer, a highly efficient ternary polymer solar cell (PSC) is obtained. By modifying the ratio of (tfmppy)2Ir(tpip) in poly[(5,6-difluoro-2,1,3-benzothiadiazol-4,7-diyl)-alt-(3,3′′′-di(2-octyldodecyl)- 2,2′;5′,2′′;5′′,2′′′-quaterthiophen-5,5′′′-diyl)] (PffBT4T-2OD): [6,6]-phenyl C71-butyric acidmethyl ester (PC71BM) blends, the short circuit current and fill factor are simultaneously enhanced, resulting in a 20.3% improvement in power conversion efficiency from 8.59% to 10.33%. Improved photovoltaic performance of ternary PSCs is mainly due to enhanced charge transportation by appropriate energy cascade alignment and enhancement crystallinity and morphology of ternary blends. It was also found that the incorporation of (tfmppy)2Ir(tpip) increased the charge carrier lifetime, ensuring efficient charge carrier transport and collection with suppressed bimolecular recombination.

Toward performance enhancement in PffBT4T-2OD-based ternary polymer solar cells by optimizing morphology and efficient charge carrier transfer

2019 Spring National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.