▎ 摘　　要

We developed a counter-doping method to tune the electronic properties of chemical vapor deposition (CVD)-grown graphene by varying the concentration and time of graphene exposure to hydrazine hydrate (N2H4 center dot H2O). The shift of G and 2D peaks of Raman spectroscopy is analyzed as a function of N2H4 center dot H2O concentration. The result revealed that N2H4 center dot H2O realized n-type doping on CVD grown graphene. X-ray photoelectron spectroscopy measurement proved the existence of nitrogen, which indicated the adsorption of N2H4 on the surface of graphene. After counter-doping, carrier mobility, which was measured by Hall measurements, increased three fold. (C) 2015 AIP Publishing LLC.