Synthesis of TiO2/rGO Nanocomposites with Enhanced Photoelectrochemical Performance and Photocatalytic Activity

In this paper, a facile and efficient method combined sol–gel method with hydrothermal process was employed for preparing titanium dioxide (TiO 2 ) ${}_2)$ /reduced graphene oxide (rGO) nanocomposites without using any reductants or surfactants. This approach leads to the reduction of graphene oxide (GO) and the growth of TiO 2 nanorods simultaneously. The results reveal that the TiO 2 short nanorods with average size of 15 $$ nm in length and 10 $$ nm in diameter were uniformly grown on the rGO sheets with high dispersion. Compared with the pure TiO 2 nanoparticles, the TiO 2 /rGO composites exhibit strong absorption in the visible light range. The photocurrent density of nanocomposites reached 0.826 $$ mA/cm 2 under the simulated sunlight illumination, which is 3.5 times than that of pure TiO 2 . An enhancement of photocatalytic hydrogen formation rate for the water splitting was observed over the TiO 2 /rGO composite photocatalysts, the fastest formation rate can reach 889.28 $$ μ $\mu$ mol ⋅ $\cdot$ g − 1 ⋅ ${}^{-1}\cdot$ h − 1 ${}^{-1}$ when TiO 2 coupling with 1wt.% rGO. Also the hydrogen production rate is about 3.27 times larger than pure TiO 2 and 2.23 times than P25 due to the excellent electron trapping and transportation properties of rGO and the synergistic effect between TiO 2 and rGO.