Investigation of highly efficient self-powered photo-detector performance of all inorganic lead-free halide perovskites (CsSnCl3) nanocrystals (NCs) decorated Er: ZnO nanowires (NWs)/Si heterojunctions

Abstract

In this study, a zero-biased or self-powered heterojunction photodetector is fabricated by using the combination of lead-free halide-based inorganic perovskite (CsSnCl3) and erbium (Er)-doped ZnO nanowires (NWs) on Si platform. The main advantages of such types of heterojunctions are cost-effective fabrication procedure, highly stable and responsive photoresponse, and, such devices exhibit low dark current and high photo-to-dark current ratio of >102. The HRTEM images confirm that CsSnCl3 perovskites nanocrystals (NCs) are randomly decorated over the ZnO NWs. The UV–visible spectroscopy shows the absorption edges and bandgaps of perovskites NCs, ZnO NWs, and combined heterojunctions. The structural, chemical compositional, and defect-related optical transitions are studied in detail by employing XRD, XPS, and PL results. The highest zero-biased photo-response at 374 nm is achieved for the 1%Er: ZnO–CsSnCl3 NWs/Si heterojunction and corresponding calculated responsivity and detectivity values are obtained to be 0.196 A/W and 2.48 × 1011 Jones, respectively. Along with it, such selective Er-doped NWs perovskites heterojunction exhibits relatively superior linear dynamic range (LDR) (51.76 dB) and rapid response speed (rise time: fall time = 83 ms:63 ms) as compared to reported values. Hence, current work demonstrates that Er-doped oxide-perovskite heterojunctions can be a promising candidate for developing high-performance UV/Visible photodetector under self-powered mode.