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

Abstract

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).