▎ 摘　　要

Tailoring the electronic properties of molybdenum disulfide (MoS2) is essential to obtain the best performance of its electronic and optoelectronic devices. Here, we report a simple methodology to improve the performance of bi-layer (BL) Mo-2 field-effect transistors (FETs) by a combination of nitrogen (N-2) gas and deep-ultraviolet (DUV) light treatment. Threshold voltages of BL MoS2 FETs shifted towards a negative gate voltage after treatment with N-2 gas in the presence of DUV light. The charge-carrier mobility of BL MoS2 was improved significantly after exposure to N-2 gas under DUV light irradiation. The carrier density of BL MoS2 was enhanced after treatment with N-2 gas in the presence of DUV light. We believe that our work may also help improve the performance of other two-dimensional nanomaterials.