Light-trapping enhanced ZnO-MoS2 core-shell nanopillar arrays for broadband ultraviolet-visible-near infrared photodetection

Two-dimensional (2D) MoS2 has important applications in the fields of photodetection, photovoltaics, and light-emitting diodes (LEDs) due to its superior electronic and optoelectronic properties. However, the planar thin-layered MoS2 usually suffers from low light-absorbing ability because of the short transmission path of incident light, which limits the photoelectric conversion quantum efficiency of the thin-layered MoS2-based photodetectors. Herein, we demonstrate a high-performance ZnO-MoS2 core-shell nanopillar (NP) array-based photodetector by depositing thin-layered MoS2 on ZnO NP arrays via magnetron sputtering. With the aid of the ZnO NP arrays, which show a strong light trapping effect, the light-absorbing ability of thin-layered MoS2 is greatly enhanced. As a result, the ZnO-MoS2 core-shell NP array-based photodetector exhibits a broadband response spanning from the ultraviolet (UV) to the visible and to the near-infrared (NIR) light region. Compared with the ZnO-MoS2 planar hetero-junction, the photocurrent of the NP array-based photodetector under illumination is improved by up to 60 times. Our work opens up new opportunities for the development of high-performance, broadband photodetectors based on 2D semiconductor materials.