Ultrafast Photovoltaic-Type Deep Ultraviolet Photodetectors Using Hybrid Zero-/Two-Dimensional Heterojunctions.

Deep ultraviolet (DUV) photodetectors have wide-range applications in satellite communications, air purification, and missile-plume detection. However, the critical barriers for the currently available wide-band gap semiconductor film-based DUV photodetectors are their low efficiency, complicated processes, and lattice mismatch with the substrate. Quantum dot (QD) devices prepared using solution-based methods can solve these problems. However, so far, there are no reports on photovoltaic-type DUV photodetectors using QDs. In this study, we propose a novel methodology to construct a hybrid zero-/two-dimensional DUV photodetector (p-type graphene/ZnS QDs/4H-SiC) with photovoltaic characteristics. The device exhibits excellent selectivity for the DUV light and has an ultrafast response speed (rise time: 28 μs and decay time: 0.75 ms), which are much better than those reported for conventional photoconductive photodetectors.