Fabrication of highly efficient TiO2/C3N4 visible light driven photocatalysts with enhanced photocatalytic activity

Abstract

Mesoporous TiO2/g-C3N4 nanocomposites with different TiO2 weight percentages have been synthesized using template as structure directing agent under mild hydrothermal conditions. XRD diffraction patterns exhibited the crystalline anatase phase of TiO2 along with distinguished peak for g-C3N4. Raman spectroscopy and FT-IR indicated the presence of TiO2 and g-C3N4 in designed heterojunctions. TEM images showed high crystallinity of TiO2 nanoparticles (size ∼15–20 nm) with porous network dispersed on 2D layered g-C3N4 sheets. N2 sorption analysis revealed large pore volume and high surface area of TiO2/g-C3N4 nanocomposites along with the mesoporous nature of TiO2. The photocatalytic efficiency of designed photocatalysts was assessed by photodegradation of methylene blue through visible light illumination. All TiO2/g-C3N4 nanocomposites revealed superior photocatalytic performance than both pure g-C3N4 and mesoporous TiO2. 10%TiO2/g-C3N4 nanocomposites revealed the highest photocatalytic performance among all prepared samples owing to its large surface area, extended visible light utilization, perfectly formed heterojunction and excellent mobility of charge carriers within the mesoporous framework. A mechanism for the destruction of MB has also been proposed. Continuous efforts for designing “smart” photocatalytic material showing wide spectral response in visible region is the present desire for the destruction of harmful pollutants.