Photocatalysis of TiO2 – Supported Graphene and Graphene Oxide Towards Phenol Degradation

Abstract

Graphene oxide (GO) was prepared using modified Hummer`s method starting from graphite. GO was impregnated on (i) commercial P25 TiO2 (Ti) and (ii) mesoporous TiO2 (mTi). The latter has higher surface area than the former one. After that, GOTi was reduced using (a) hydrogen gas at different temperatures or (b) hydrazine hydrate in microwave using a cyclic technique. Characterization of all used materials was carried out using bulk and surface techniques e.g. XPS, XRD, Raman Spectroscopy, FTIR, SEM, UV-Vis diffuse reflectance, BET, and cyclic voltammetry. The photocatalysis behavior of the synthesized GOTi, GOmTi, RGOTi and RGOTi were tested towards the phenol degradation and compared against the standard commercial P25 TiO2 in presence and absence of H2O2 which was either (i) added to the reaction mixture or (ii) generated locally within the reactor .The study revealed that the TiO2 – supported RGO and GO are showing much higher electrocatalytic performance above the P25 TiO2. Table 1 shows the phenol degradation (60 ppm) after 6 h in presence of different volume of H2O2 over Ti, 0.2-GoTi and 0.1-GGO.