Modified interfaces of ZnO thin films through MoS2 addition in precursor solution for MoS2/ZnO heterojunctions and their enhanced ultraviolet photodetection properties

In this study, a MoS2/ZnO heterostructure with type-II band alignment was successfully synthesized via a simple hydrothermal and sol-gel spin-coating method using a MoS2 added precursor solution. The surface of the MoS2/ZnO thin films consisted of MoS2 particles. In addition, type-II band alignment was observed at the interface between ZnO and MoS2, which facilitated the transfer of electrons and holes under UV illumination. With respect to UV photoresponse characteristics, the MoS2/ZnO thin films with the MoS2 concentration of 0.2 M showed significantly higher photocurrent than all the other thin films investigated. In addition, these thin films showed faster UV photoresponse and highly improved photoresponsivity, photosensitivity, and photoselectivity. Thus, the MoS2 concentration of 0.2 M was found to be optimum for the preparation of MoS2/ZnO heterojunction thin films with excellent UV photoresponse characteristics to overcome the limitations of ZnO-based UV photodetectors.