In summary, the OH• radicals generated at the TiO2 surface lead to oxidative attack on the carbon-rich RGO, which is ultimately mineralized as evident from the decreased TOC concentration with increasing irradiation time. However, the distinct difference in the rate of the RGO absorption loss and TOC depletion during OH• attack points to an early fragmentation process during the oxidation of RGO that could lead to release of PAH-like compounds. Caution must be exercised in pursuing the TiO2-RGO assembly in future photocatalytic studies.