Efficient ternary organic solar cells based on a twin spiro-type non-fullerene acceptor

摘要: Abstract A novel small-molecule (SM) acceptor DTF-IC is designed and synthesized in this work. The power conversion efficiency (PCE) of ternary OSCs increased up to 12.14% from 10.90% by incorporating 10 wt% as second acceptors into the binary consisting PBDB-T donor IT-M acceptor. This was mainly due large increase short-circuit current (Jsc) 16.18 17.95 mA/cm2, without any drop open-circuit voltage (Voc) fill factor (FF). addition enabled form a distinct complementary absorption profile visible-light region, which boosted photon harvesting range 730–800 nm consequently Jsc system 11%. Moreover, there an energy transfer between two SM acceptors, favorable for enhancing charge separation well reducing recombination at PBDB-T:IT-M PBDB-T:DTF-IC interface. Simultaneously, HOMO LUMO levels were lower than those PBDB-T, but still higher IT-M. Thus, able provide cascading level with host are beneficial efficient facilitating exciton dissociation carrier transport. Meanwhile, highly crystalline third component can improve crystallization process active layer while maintaining proper phase separation. work proposes idea non-fullerene achieved via twin spiro-type structure modifying indanone provides new direction selection solar cell materials.