Vacancy Sealing with Pyridine Molecules Lowers Interfacial Trap Density and Accelerates Charge Extraction in Organic Photovoltaics.

ABSTRACT: In organic photovoltaics (OPVs) using zinc oxide (ZnO) as the electron transport layer (ETL), radicals generated in the oxygen vacancies of ZnO interfere with the π-π stack structure of the upper organic photoactive layer. The disruption of π-π stacking by these radicals hinders charge transfer and increases recombination losses. If this disruption continues, it eventually impairs the operational stability of the device. To mitigate these effects, pyridine (Py)-based passivation is explored. Among various candidates, 4-tert-butylpyridine (4TPy) is most effective in preserving π-π stacking, enhancing interfacial charge extraction, and suppressing radical formation. Incorporation of 4TPy into the device architecture improved the fill factor (FF) from 74.1 ± 0.7% to 78.0 ± 0.9% and power conv

SUBMITTER: Kim SJ 

PROVIDER: S-EPMC12632431 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature