A novel optical management layer with flexible color tunability and high transmittance in organic solar cells

Abstract

The evaluation of colored semi-transparent organic solar cells (ST-OSCs) relies on the power conversion efficiency (PCE) and peak transmittance across the visible light spectrum. However, it is a significant challenge to enhance both parameters simultaneously. In this study, we investigate the impact of different film systems for the Ag electrode on transmittance enhancement using an optical interference formula derived for anti-reflective films. As a result, a novel ZnS/WO3 double-layer anti-reflective film is introduced as an optical management layer. The ZnS/WO3/Ag structure achieves a peak transmittance exceeding 75 % across the visible light spectrum while also offering customizable color attributes. Upon electrical simulation, the power conversion efficiency (PCE) of organic solar cells with 15 nm Ag and 80 nm PM6:Y6 reached to 11.72 %, and an ideal PCE value of 14.53 % is achieved by reducing non-radiative recombination. Through optical simulations, it has been demonstrated that the integration of a ZnS/WO3 double-layer anti-reflective film with organic solar cells enables the generation of OSCs in vibrant purple, blue, cyan, and green hues. Notably, these OSCs exhibit their highest peak transmittance at blue light (452.5 nm), reaching an impressive value of 50.49 %. These remarkable findings not only showcase exceptional performance but also highlight significant potential in applications involving colored OSCs utilizing the new optical management layer composed of ZnS/WO3 double-layer anti-reflective films.