Design and Synthesis of a Novel n‐Type Polymer Based on Asymmetric Rylene Diimide for the Application in All‐Polymer Solar Cells

A novel n‐type polymer of PTDI‐T based on asymmetric rylene diimide and thiophene is designed and synthesized. The highest power conversion efficiency of 4.70% is achieved for PTB7‐Th:PTDI‐T‐based devices, which is obviously higher than those of the analogue polymers of PPDI‐2T and PDTCDI. When using PBDB‐T as a donor, an open‐circuit voltage (VOC) as high as 1.03 V is obtained. The results indicate asymmetric rylene diimide is a kind of promising building block to construct n‐type photovoltaic polymers. The first n‐type polymer based on the asymmetric rylene diimide is designed and synthesized. PTDI‐T could realize a power conversion efficiency of 4.70% by using PTB7‐Th as a donor polymer, which is obviously higher than those of the analogue polymers of PPDI‐2T and PDTCDI.