Developing high-performance direct-current (DC) nanogenerators capable of operating effectively in high relative humidity remains a significant challenge. In this work, we propose an innovative approach to enhance the output performance of direct current triboelectric nanogenerator (DC-TENG) by integrating a composite membrane of polyvinylidene fluoride (PVDF) and ionic liquid (IL). When friction occurs, the IL/PVDF composite membrane forms a Schottky junction at the IL/PVDF-metal interface, facilitating proton release and creating a proton concentration gradient. This process promotes charge transfer through the accumulation of built-in net negative charges on the IL/PVDF composite membrane, resulting in substantial improvements in current output, particularly in humid environments. As a result, the IL/PVDF20-TENG achieved a peak current of 1.18 mA and a voltage of 1.36 V, corresponding to increases of 195-fold and 1.2-fold, respectively, compared to PVDF-TENG. Additionally, the device exhibited a power density of 15.4 µW/cm², measured through the external resistance method. These findings underscore the promise of IL/PVDF composite membranes as an effective solution for developing current-adjustable DC-TENG, offering widespread applications in self-powered technologies while minimizing reliance on external energy sources.
