Scalable and cost-effective fabrication of high-performance self-powered heterojunction UV-photodetectors using slot-die printing of triple-cation lead perovskite coupled with triboelectric nanogenerators

The demand for continuous monitoring of ultraviolet (UV) radiation, which poses significant health risks, has grown significantly with the advent of the internet of things (IoT) for human health. The need for a self-powered system that does not rely on battery charging in environmental conditions has led to the exploration of triboelectric nanogenerators (TENGs) as a promising energy source for sensor systems. In this study, we present a fully printed UV photodetector (UV-PD) that is fabricated through scalable slot-die printing of either single-layer triple-cation mixed halide perovskite (TCMHP) or a heterojunction of TiO₂/TCMHP on patterned fluorine-doped tin oxide (FTO). The integrated TENG generates the required energy from the tapping of Kapton to the FTO contact, making the device self-powered. Our self-powered PD exhibits an excellent responsivity and detectivity of 71.4 mA W⁻¹ and 6.92 × 10¹⁰ Jones, respectively, under a 395 nm wavelength, significantly outperforming spin-coated TCMHP-based devices. We further optimized the performance of our integrated TENG-powered heterojunction TiO2/TCMHP UV-PD by fabricating sensors with groove spacings of 2, 3, 5, and 8 mm. The optimized device demonstrated an unprecedented responsivity, detectivity, and EQE% of 151.9 mA W⁻¹, 1.29 × 10¹¹ Jones, and 47.8%, respectively, under UV irradiation. Our work represents a significant step towards large-scale industrial flexible self-powered UV detection devices that can protect human health and safety. This study highlights the potential of scalable and cost-effective slot-die printing techniques for the industrial production of high-performance self-powered UV sensors, with significant implications for IoT-based health monitoring and environmental protection applications.