Flexible hybrid nanogenerator coupling of triboelectric and photovoltaic effects based on fluoride dielectric regulation for energy harvesting

Recently, constructing hybrid nanogenerators (NGs) that can simultaneously harvest frictional and solar energies has attracted a growing interest, among which halide perovskite is considered as one of the most suitable active materials. However, current perovskite-based hybrid NGs are low in performance and limited to rigid substrates. Strategies to minimize performance loss caused by deep defects in perovskite functional layer are still lacking. In this work, we proposed a fluoride additive passivation strategy to fabricate a new kind of flexible, efficient perovskite-based hybrid NGs. The fluoride with high electronegativity can effectively passivate defect density of perovskite film and further enhance its dielectric constant to minimize the ability of defects to capture charges. Hence, more efficient charge transport and suppressed recombination loss are achieved, which maximizes the triboelectric-photovoltaic coupling effect. The maximum current of the hybrid NG is up to 9.7 μA under illumination, which is about 25 times higher than that of the control device. The hybrid NG could light 50 LEDs and charge capacitors. Moreover, it exhibited excellent flexibility to act as a self-powered wearable sensor to detect human motions. Our work proposed a new strategy for flexible triboelectric-photovoltaic hybrid NGs with high-output performance for smart wearable applications.