Controlled doping, as a cornerstone of the semiconductor industry, becomes one of the most important topics for two-dimensional (2D) semiconductors such as tungsten disulfide (WS 2 ), with intriguing physical properties. Here, we present a facile, controllable and reversible strategy for surface charge transfer doping in the monolayer WS 2 crystals. After triethylamine treatment, the field effect transistors (FETs) based on monolayer WS 2 exhibit enhanced mobility up to 28.6 cm 2 V −1 s −1 , which is much larger than that of the pristine one (9.8 cm 2 V −1 s −1 ). In addition, the n-doping via triethylamine treatment can also improve the photoresponsivity of the device, i.e. from pristine 6.4 × 10 −3 AW −1 to the doped 21 AW −1 . Interestingly, the electron transport properties of the doped WS 2 can be recovered to be close to that of the intrinsic WS
Published in: "2DMaterials".