Trap State Suppression Enabled by Modulated Donor Crystallization in Non-Halogenated Organic Photovoltaics
발표자
이다민 (경북대학교)
연구책임자
차효정 (경북대학교)
초록
내용
This study investigates tail states as key contributors to recombination-induced voltage loss through enhanced bimolecular recombination in organic photovoltaics (OPVs) processed with non-halogenated solvents. Grazing incidence wide-angle X-ray scattering (GIWAXS) reveals that the incorporation of PM6 promotes a more ordered face-on molecular orientation within the D18 donor layer. This improved molecular ordering suppresses carrier trapping associated with tail-state-induced energetic disorder—one of the primary causes of bimolecular recombination and voltage loss. Transient photovoltage and photocurrent measurements further confirm that the reduction in tail-state energy levels limits charge recombination and prolongs carrier lifetimes, ultimately leading to enhanced device efficiency. Collectively, these findings highlight the critical role of donor molecular orientation in regulating energetic disorder in LbL-processed OPVs.