Coupled semiconductor nanocomposite g-C 3 N 4 /TiO 2 with enhanced visible light photocatalytic activity

Abstract The visible light photocatalytic activity of graphitic carbon nitride, g-C 3 N 4 , can be enhanced by coupling with other semiconductors. In this work, mesoporous TiO 2 nanoparticles were grown over g-C 3 N 4 sheets resulting in the coupled nanocomposite photocatalyst. The morphological analyses using FE-SEM, TEM and AFM revealed the uniform deposition of TiO 2 on g-C 3 N 4 sheet. The visible light photocatalytic activity of g-C 3 N 4 and g-C 3 N 4 /TiO 2 composites were tested by methyl orange (MO) dye degradation and Cr(VI) reduction. The results revealed an enhancement in the visible light photocatalytic activity of g-C 3 N 4 when it was coupled with TiO 2 in the nanocomposite. Mesoporous TiO 2 nanoparticles deposited over g-C 3 N 4 provides the necessary large surface for the adsorption of the pollutant molecules. The enhanced visible light photocatalytic activity of g-C 3 N 4 in the nanocomposite is due to the high surface area and efficient photogenerated charge carrier separation in the nanocomposite as evidenced in photoluminescence (PL) results.