This study proposes a strategy to gamma (γ) irradiation on Zinc Oxide (ZnO) as an electron transport layer (ETL) in organic photovoltaics (OPVs) and organic photodetectors (OPDs). ZnO is used in optoelectronics due to its high charge mobility and wide bandgap. However, its performance is limited by photosensitivity and oxygen vacancies. We systematically analyzed changes in the structural, optical, and electrical properties of ZnO films after exposure to varying doses of γ-radiation. Structural and chemical modifications induce a reduction in oxygen vacancies shift in the absorption spectrum and a decrease in the optical bandgap, confirmed by X-ray photoelectron spectroscopy (XPS) and UV-vis spectroscopy, respectively. Consequently, the reduced trap density effectively suppresses dark current, leading to enhanced specific detectivity (D*) in OPDs and improved power conversion efficiency (PCE) in OPVs through promoted photocurrent generation and reduced dark current.