Photocatalytic Degradation of Pesticide with TiO2 Anchored on g-C3N4/Exfoliated g-C3N4 Under Visible Light Irradiation

Indiscriminative use of pesticides in food production results in contamination of water and creates a serious hazard to environment. Semiconductor photocatalysis emerge as a new promising alternative technology for efficient degradation of such organic pesticide. The efficient use of solar energy and a promising catalyst in photocatalysis makes the process most economical for the practical application. TiO₂ is currently the cheapest, non-toxic, high stability and low cost catalyst. However the rapid electron-hole recombination effect of TiO₂ and its response in UV light range limited its applications. The above shortcoming is overcome by constructing TiO₂ hybrid system with g-C₃N₄/ exfoliated g-C₃N₄

In this approach a comparison of TiO₂ hybridized with g-C₃N₄ and exfoliated g-C₃N₄ was studied. The g-C₃N₄ have typical physicochemical properties like lower band gap energy, two dimensional layered structure similar to graphene oxide, high specific surface area etc. However exfoliation of layered g-C₃N₄ into single nanosheets shows improved optical and electronic properties with high surface area and found a potential application in energy storage, biotechnology field, energy conversion etc.

An efficient visible light driven, TiO₂ anchored on g-C₃N₄/exfoliated g-C₃N₄ composites were prepared via multistep method including sol-gel and hydrothermal method. Anatase phase of TiO₂ was effectively loaded on 2D g-C₃N₄. The band gaps of nanocomposites have been diminished on introduction of g-C₃N₄ and results in complete degradation of pesticide into CO₂ and H₂O.