4. Conclusions
In this study nanostructured membranes based on electrospun nanofibers and TiO2-graphene photocatalyst spread over their surface were produced and characterized in two different conformations: the layer by layer and the nanocomposite ones. With respect to the membrane that contains solely TiO2, all the composite membranes showed higher photocatalytic efficiencies, which should be attributed to the synergetic charge transfer effect of the composites, as well as to a reduction of the TiO2 band gap, according to the literature. It has been revealed that both the layer by layer configuration (Type B) and the nanocoposite one (Type C) led a complete photo-degradation of gas-phase methanol to CO2 and water, even if with different kinetic constant. Different concentrations of co-photocatalyst were tested and it has been depicted that there is a threshold limit over which the graphene light adsorption is predominant with a consequent effect of the reduction of the light utilization efficiency of TiO2. The obtained results are promising and makes these active filter media as a good candidate in the development of advanced solutions for indoor environmental quality.