High-performance UV-Vis-NIR photodetectors based on perovskite/PDPP3T polymer composites

The composite thin film photodetector in this study combines the characteristics of MAPbI3 material for near -ultraviolet-visible light and PDPP3T:PC71BM material for near-infrared light absorption, resulting in efficient light harvesting. To fabricate high-performance photodetectors, we optimized the photodetector structure, thin film fabrication process, solute concentration, and photoactive layer thickness. Finally, we obtained a photo -detector with a broad spectral detection range in the near-ultraviolet-visible-near-infrared (UV-vis-NIR). The detectivity (D*) of our prepared UV-vis-NIR photodetector at 380 nm, 655 nm and 848 nm is 1.24 x 1013 jones, 2.13 x 1013 jones and 1.59 x 1013 jones, respectively. This is one of the best performances among polymer photodetectors reported so far and is comparable to commercial inorganic silicon-based PDs. In addition, the optimal composite thin film photodetector exhibits a fast response speed (trise/tfall = 109/49 mu s), a linear dy-namic range of 100 dB, and excellent stability. Furthermore, the PDPP3T:PC71BM active layer can effectively suppress the leakage current in the reverse biased region, which enables the device to obtain an ultra-low dark current density (Jdark) of 8.58 x 10-10 A cm-2. This study explores a new avenue for high-performance pho-todetectors based on mixtures of perovskites and low-bandgap photoactive polymers.