Synthesis, characterization and photodegradation activity of graphitic C₃N₄-SrTiO₃ nanocomposites

Porous graphitic nitride (gC₃N₄) by template free simple condensation and SrTiO₃ nanocubes by sol-gel method were synthesized. Composites containing Different percentages of pGCN were prepared (x% pGCN-ST where x = 5, 10, 30, 50 & 70%). The as synthesized composites were characterized by various instrumental techniques such as X-Ray diffractometer, Fourier transform infrared spectrophotometer, BET surface area analyzer, UV Visible diffuse reflectance spectrophotometer, X-Ray photoelectron spectrophotometer, SEM with Energy dispersive X-ray analyzer (SEM/EDAX) and elemental mapping, Transmission electron microscope, Photoluminescence spectrophotometer and Electrochemical impedance. The composite catalysts were evaluated for their photocatalytic degradation of reactive blue 198 (RB 198), reactive black 5 (RB 5) and reactive yellow 145 (RY 145) in the presence of visible irradiation. Among the different composites 50% pGCN-ST catalyst showed remarkable decolourization of all the three dyes under different irradiation (UV, visible and solar). Kinetics studies were revealed that the photodecolourization reaction followed pseudo first order. TOC and COD studies confirmed that the dyes were mineralized significantly. A possible mechanism for photocatalytic degradation was also proposed in this study.