Enhanced photocatalytic activity of g-C3N4-TiO2 nanocomposites for degradation of Rhodamine B dye

g-C3N4-TiO2 nanocomposites have been synthesized by simple chemical route with high photocatalytic activity under visible light irradiation. Different weight ratio of catalyst were used for the photodegradation of Rhodamine B dye. It was observed that the composite with 2:1 wt ratio of g-C3N4 and TiO2 respectively shows maximum photocatalytic activity with photocatalytic rate as ∼0.17 min−1 which is ∼10 times higher than pure TiO2. At an optimal concentration of g-C3N4, lifetime of the excited electrons was found to increase from 2.65 to 10.20 ns in the composite compared to TiO2, suggesting efficient separation of electrons and holes. The favorable band position of g-C3N4 and composite supports the increase in the charge separation rate of electron and hole during photocatalytic reaction. The role of active species involved in the degradation of the organic dye during photocatalysis by g-C3N4-TiO2 has been investigated (like radical species).