Enhancing photocatalytic performance of Co-TiO2 and Mo-TiO2-based catalysts through defect engineering and doping: A study on the degradation of organic pollutants under UV light

Abstract

Nanostructured photocatalysts based on cobalt and molybdenum-doped TiO2 composite materials were developed to enhance photocatalytic performance. The creation of defects through partial carbothermal reduction resulted in materials with lower band gaps, improving efficiency. The carbon lattice facilitated electron movement and inhibited electron-hole recombination, while the large surface area of the nanosheets enhanced catalyst effectiveness. The materials were characterized using XRD, FTIR, Raman spectroscopy, FESEM, and UV–Vis spectroscopy. The degradation of arsenazo 3 dye was used to evaluate the catalysts, with all three showing efficient degradation. The TiO2-Mo-C catalyst exhibited the highest degradation rate (99.8%). Kinetic data indicated that the photodegradation followed pseudo-first-order and Langmuir-Hinshelwood kinetics. Remarkably, the reaction rate constant (kC = 41.61 mg L-1 min−1) and adsorption equilibrium constant (KLH = 1.26 × 10-3 L mg−1) of the TiO2-Mo-C catalyst were significantly superior to other catalysts. These photocatalysts demonstrated excellent stability and reusability over six cycles.