The effect of fluorination of naphthalene diimide copolymer based acceptor on energy level and blend morphology in all-polymer solar cells = The effect of fluorination of naphthalene diimide copolymer based acceptor on energy level and blend morphology in all-polymer solar cells

다국어 초록 (Multilingual Abstract)

Tuning the chemical structures of conjugated polymers by fluorination is a simple, yet powerful strategy for regulating their energy level and blend morphology between donor and acceptor. Herein, we investigate the effect of fluorination to P(NDI2OD-T2), the most generally used as acceptors in all-polymer solar cells (all-PSCs), on their photovoltaic properties. We developed all-PSCs based on PBDTTTPD as donor and P(NDI2OD-T2F) as acceptors, and examined their charge generation and recombination behaviors by TAS. These systems exhibit faster hole transports and longer polaron life time, and subsequently the high power conversion efficiency of 6.09%, compared with control devices using P(NDI2OD-T2) as acceptors (2.02%). Furthermore, higher miscibility of P(NDI2OD-T2F) with donors in blend films was also examined by AFM and R-SoXS. Therefore, we concluded that fluorination is effective strategy for high efficient all-PSCs due to deepening energy level and producing miscible morphology.