Impacts of static and dynamic disorders on the intramolecular exciton transport in organic solar cells

Abstract

Based on great importance of the exciton transport in the thick-film organic solar cells (OSCs), intramolecular exciton transport along polymer chains is theoretically studied with two types of static and dynamic intramolecular disorders, namely the diagonal disorder and the off-diagonal disorder included. The results demonstrate that the static diagonal disorder (SDD) has no impacts on the exciton transport, while the large static off-diagonal disorder (SOD) would result in large potential barriers to hinder the exciton transport. Especially, the strong SOD will result in some larger potential barriers that stop the exciton transport and form the trapped exciton state. Moreover, both dynamic diagonal disorder (DDD) and dynamic off-diagonal disorder (DOD) are found to be favorable to the exciton transport. Importantly, when considering the SOD and DOD simultaneously, the DOD is found to help the trapped exciton state to overcome the binding potential barriers derived from the SOD. These results provide valuable insights into developing high-efficiency thick-film OSCs.