Ag Nanowires-Enhanced Sb2Se3 Microwires/Se Microtube Heterojunction for High Performance Self-Powered Broadband Photodetectors.

The implementation of photoelectric conversion in photoelectric integrated systems requires the design of photodetectors (PDs) with quick response times and low power consumption. In this work, the self-powered photodetector was prepared by antimony selenide (Sb2Se3) microwires (MW)/Se microtube (MT) heterojunction by coating Ag nanowires (NW). The incorporation of Ag-NW involves dual enhancement mechanisms. First, the surface plasmon resonance (SPR) effect amplifies the light absorption across UV-vis-NIR spectra, and the conductive networks facilitate the rapid carrier transport. Second, the type-II band alignment between Sb2Se3 and Se synergistically separates photogenerated carriers, while the Ag-NW further suppress the recombination through built-in electric field modulation. The optimized device achieves remarkable responsivity of 122 mA W-1 at 368 nm under zero bias, with a response/recovery time of 8/10 ms, outperforming most reported Sb2Se3-based detectors. The heterostructure provides an effective strategy for developing self-powered photodetectors with broadband spectral adaptability. The switching ratio, responsivity, and detectivity of the Sb2Se3-MW/Se-MT/Ag-NW device increased by 260%, 810%, and 849% at 368 nm over the Sb2Se3-MW/Se-MT device, respectively. These results show that the addition of Ag-NW effectively improves the photoelectric performance of the Sb2Se3-MW/Se-MT heterojunction, providing new possibilities for the application of self-powered optoelectronic devices.