Perovskite–Gold Nanorod Hybrid Photodetector with High Responsivity and Low Driving Voltage

The optical and electronic properties of noble metallic nanoparticles can be exploited to enhance the performance of inorganic/organic photodetectors. In this work, a uniformly distributed layer of Au nanorods (AuNRs) is integrated into vertically structured perovskite photoconductive photodetectors and, as a result, perovskite–AuNR hybrid photodetectors that exhibit significant photocurrent enhancements are reported. Ultimately it achieves a responsivity of ≈320 A W⁻¹ at a low driving voltage of −1 V. This is an improvement of 60% compared to the responsivity of pristine devices (≈200 A W⁻¹). The high responsivity and low driving voltage place this device among the highest performing perovskite-based thin-film photoconductive photodetectors reported. The stability and linearity of the photoresponse following repeated light/dark cycles are characterized. The hybrid device also shows a fast response (with the decay time of ≈95 ns) compared to pristine devices (≈230 ns). The improvements in photodetection performance are attributed to plasmon-enhanced optical absorption, as well as advances in charge extraction and transport.