Enhancement of Photoluminescence in CsPbBr₃ Nanocrystals with 1-Octanethiol by Light Illumination for Potential Emitting Applications

Metal halide perovskite nanocrystals (NCs) are emerging for emitting applications due to their high photoluminescence (PL) quantum yield and wide PL wavelength tunability. Here, the light-induced PL enhancement in complexes of CsPbBr₃ NCs and 1-octanethiol (OT) molecules (refers to below as NC-OT complexes) is investigated. In comparison with that of as-grown CsPbBr₃ NCs, the PL intensity of NC-OT complexes is lower before light illumination. While after ultraviolet light illumination, the PL performance of NC-OT complexes is improved in both air and nitrogen atmospheres. Compared with air atmospheres, anaerobic atmospheres are more effective at increasing the PL intensity because of eliminating photo-oxidation. The light illumination prevents the nonradiative process and enhances the radiative emission in NC-OT complexes, supported by transient PL and photobleaching measurements, due to better surface passivation through thiol-ene reactions. The light-induced PL enhancement in NC-OT complexes provides valuable information for the applications of perovskite nanomaterial-based emitting devices.