Blade-coated efficient and stable large-area organic solar cells with optimized additive

For the fabrication of large-area devices, achieving both excellent photovoltaic performance and device stability simultaneously is the key to commercialization of organic solar cells (OSCs). Herein, non-fullerene OSCs with various additives (1,8-diiodooctane (DIO), 1,8-octanedithiol (ODT), chloronaphthalene (CN)) were fabricated by blade-coating in ambient environment. It was demonstrated that all these three additives can improve device performance. However, CN based device shows only a slightly increased power conversion efficiency (PCE) of 9.34% as compared to the device without additive (PCE = 9.19%). Although DIO based device presents an increased PCE of 9.87%, the corresponding device stability is poor. Impressively, due to the enhanced crystallization as well as the small and pure domains, the device with ODT additive not only possesses higher photovoltaic performance (PCE of 10.20%), but also exhibits better device stability. In addition, ODT based large-area device (90 mm²) prepared by blade-coating also exhibits a high PCE of 8.59%, showing great potential in fabricating efficient and stable large-area organic solar cells.