Self-Patterned CsPbBr3 Nanocrystal Based Plasmonic Hot-Carrier Photodetector at Telecommunications Wavelengths

Extending the photodetection range of lead halide perovskites into the near-infrared telecommunications bands can not only enable a wide-spectrum solar energy harvesting, but pave ways for important applications in biodetection, infrared imaging, and telecommunication. However, there is a lack of an effective means to apply lead halide perovskites for efficient photodetection covering a wide wavelength range in the telecommunications bands. Here, CsPbBr3 nanocrystal- (NC-) based photodetector operating at wavelengths in the telecommunications bands via surface plasmon-induced hot holes is demonstrated. The internal photoemission of the plasmon-induced hot holes from plasmonic antennas into CsPbBr3 NCs enables a photocurrent at wavelengths around 1550?nm. Moreover, a solvent treatment is also performed on drop-casted CsPbBr3 NC thin film leading to a nanoscale self-patterning with a compact and uniform morphology. This treatment benefits the carrier transportation contributing to a detectable photoresponse and minimizes the optical scattering so that the CsPbBr3 NCs can be integrated into the plasmonic structure without damping its resonant feature. Consequently, the CsPbBr3 NC-based plasmonic hot-carrier device achieves polarization discrimination and wavelength-selective photodetection without additional optical components. ? 2021 Wiley-VCH GmbH