Anatomy of the energetic driving force for charge generation in organic solar cells.

ABSTRACT: Eliminating the excess energetic driving force in organic solar cells leads to a smaller energy loss and higher device performance; hence, it is vital to understand the relation between the interfacial energetics and the photoelectric conversion efficiency. In this study, we systematically investigate 16 combinations of four donor polymers and four acceptors in planar heterojunction. The charge generation efficiency and its electric field dependence correlate with the energy difference between the singlet excited state and the interfacial charge transfer state. The threshold energy difference is 0.2 to 0.3 eV, below which the efficiency starts dropping and the charge generation becomes electric field-dependent. In contrast, the charge generation efficiency does not correlate with the energ

SUBMITTER: Nakano K 

PROVIDER: S-EPMC6555791 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature