Broadband, sensitive and spectrally distinctive SnS_(2) nanosheet/PbS colloidal quantum dot hybrid photodetector

Photodetectors convert photons into current or voltage outputs and are thus widely used for spectroscopy,imaging and sensing.Traditional photodetectors generally show a consistent-polarity response to incident photons within their broadband responsive spectrum.Here we introduced a new type of photodetector employing SnS_(2) nanosheets sensitized with PbS colloidal quantum dots(CQDs)that are not only sensitive(~105AW−1)and broadband(300–1000 nm)but also spectrally distinctive,that is,show distinctive(positive or negative)photoresponse toward incident photons of different wavelengths.A careful mechanism study revealed illumination-modulated Schottky contacts between SnS_(2) nanosheets and Au electrodes,altering the photoresponse polarity toward incident photons of different wavelengths.Finally,we applied our SnS_(2) nanosheet/PbS CQDs hybrid photodetector to differentiate the color temperature of emission from a series of white light-emitting diodes(LEDs),showcasing the unique application of our novel photodetectors.