Preparation, characterization and photocatalytic degradation kinetics of Reactive Red dye 198 using N,Fe codoped TiO2 nanoparticles under visible light

In this paper, we report the detailed kinetic and mechanistic study using N, Fe codoped TiO2 for the degradation of Reactive Red dye 198 (RR dye 198) under visible light. The N, Fe codoped TiO2 was prepared by sol-gel method using urea and ferric nitrate as the dopant source and well characterized by XRD, FTIR, DRS, TEM, XPS, EDX, and BET techniques. The N, Fe codoped TiO2 nanoparticles were found to be 95.55% anatase and 4.45% rutile phase, with a narrow particle size distribution of 4-7nm, having band bap of 2.4eV, surface area of 98.01m(2)g(-1), and are cubic in shape. The process conditions for photocatalytic degradation of RR dye 198 using N, Fe codoped TiO2 under visible light have been optimized by varying operational parameters such as catalyst loading, pH, initial concentration of the substrate, and the effect of electron acceptors have been examined. The addition of H2O2 as a co-oxidant showed an anomalous behavior in the degradation pattern. The degradation followed first-order kinetics with r(0) of 3.036mgL(-1)min(-1) at natural pH and obeyed the Langmuir-Hinshelwood model. The mechanism of degradation has been investigated with the help of radical quenchers. The GC-MS analysis of the residue after degradation depicted the degradation pattern of the dye under optimized conditions.