Versatile organic photovoltaics with a power density of nearly 40 W g(-1)

Maximizing the efficiency while exploiting the fully inherent advantages of organic photovoltaics (OPVs), e.g., ultra-flexibility, ultra-lightweight, rich color, etc., is of great significance for the commercialization of OPVs. To address this, here we implant the top-illuminated devices on 1.3 mu m polyimide substrates and demonstrate ultra-flexible OPVs with tunable colors, record efficiency and power densities, via delicate design of device configurations and selection of fabrication processes. Specifically, the optimized morphology of a transparent Ag electrode and the optical interference effect are utilized to improve the photovoltaic performances and realize a wide color gamut, respectively. Thus, the corresponding devices achieve a benchmark efficiency of 17.32%, and this efficiency remains almost unchanged after peel-off processing and 5 000 compression-release deformation cycles. Encouragingly, the obtained ultra-thin OPVs exhibit an excellent power-to-weight ratio of 39.72 W g(-1), which is the best value among all PV technologies. These results prove that our OPVs have outstanding adaptivity to be diversified for extreme application scenarios.