An Ultraviolet‐to‐NIR Broad Spectral Nanocomposite Photodetector with Gain

photodetector; the corresponding responsivity and normalized detectivity were 0.5 A/W and 2.3 × 10 9 Jones, respectively. [ 19 ] It is reasonable to anticipate a better detector performance if the photon-to-current conversion effi ciency can be further improved. In this manuscript, we report a PbS-based NIR hybrid photodetector with an EQE above 100% by the integration of zinc oxide (ZnO) QDs to induce a photoconductive gain. The active layer of the photodetector can be prepared by a single cycle of spin-coating. Moreover, the photodetector shows a tenfold higher responsivity than that of commercial SiC and Si photodetectors in the UV‐visible range at room temperature. The structure of the dual-QD hybrid photodetector is presented in Figure 1 a. The device structure is similar to bulk heterojunction solar cells with indium tin oxide (ITO) and aluminium used as the anode and cathode, respectively. Both PbS and ZnO QDs were introduced into the polymer blends. The PbS QDs in this study were synthesized by a hot-injection technique involving the quick injection of bis(trimethylsilylsulphide) into a hot lead precursor. [ 21‐23 ] The average diameter of PbS QDs was about 3.3 nm (maximum 3.7 nm), calculated from the

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