Photovoltaic contribution of photo-generated excitons in acceptor material of organic solar cells

摘要

Abstract Contribution of exciton generation in acceptor material to the photovoltaic performance of three bulk-heterojunction organic solar cells (BHJ OSCs), PTB7:PC71BM, P3HT:ICBA and P3HT:PC61BM are studied. Singlet and triplet rates of absorption and dissociation and diffusion lengths are calculated and compared with those when excitons are generated in the donor of these BHJ OSCs. It is found that the rates of absorption and dissociation and diffusion lengths are comparable whether excitons are generated in donor or acceptor of these BHJ OSCs. Therefore, it is proposed that the contribution of exciton generation in acceptor may not be negligible.