Work function evolution of graphene oxide by utilizing hydrothermal treatment

In this paper, hydrothermal treatment is applied for graphene oxide (GO) reduction. Tunable work function of hydrothermal treated GO (HTGO) is facilitated by controlling hydrothermal temperature and duration time, in comparison, CVD grew graphene (CVD-G) are also prepared. Work function of GO is tuned in the range of 5.72 eV to 4.43 eV. Progressing descend of peak intensity at higher binding energy region for which belonging to oxygen-containing functional group (c.a. 286 eV to 290 eV) in C1s XPS spectra indicated controllable reduction of hydrothermal treatment. The X-ray absorption near edge structure (XANES) spectra, indicates the increased sp² to sp³ ratio in accordance with the raise of hydrothermal temperature, consistent with the increased conductivity with increment amount of sp² species in HTGOs.