The final step of the LbL assembly procedure, i.e., membrane post-treatment by ethanol and UV, also helped enhance the photocatalytic performance of the TiO2–GO membrane. As shown in Fig. 7(a), the MB degradation kinetics was slightly faster after the ethanol–UV treatment. This is most likely because such a treatment partially reduced GO, thereby enhancing the capability of GO in conducting electrons from TiO2 nanoparticles and thus further improving the photocatalytic properties. The reduction of GO was confirmed by XPS analysis. As shown in Fig. 7(b), the oxygen content of the TiO2–GO membrane decreased by about 5% (of the total contents) after ethanol and UV treatment.