Clarifying the performance dominance of crystallization and phase separation on organic photovoltaics and photodetectors

Abstract

Herein, a series of photodiode devices based on PM6:BO-4Cl system with 100 nm (thin) or 300 nm (thick) active layer thicknesses treated by various additive ratios are carefully studied. Based on acquired morphological characteristics, device performance data, and carrier dynamic features, several new understandings can be concluded: (1) the additive-induced morphology evolution towards large agglomerates perform better in thick-film OPV than refined fibrillar structure does; (2) thick-film OPD doesn't show up significant performance advantages than thin-film counterpart; (3) energetic disorder shows no clear correlation with dark current, whereas trap density and charge generation coupling are more critical. In addition, the obtained 16.18 % PCE is located at the top level for thick-film OPV processed by ortho-xylene, a representative green solvent in research field. Our work establishes a comprehensive database for the typical donor/acceptor system, which helps deducing new understandings on property-performance relationship for film state morphology under both OPV and OPD working modes.