Synthesis and Optimization of TiO2 Photocatalyst Using Biomass-Derived Activated Carbon for Photocatalytic Degradation of Methyl Orange

Abstract

TiO2 is normally a preferred photocatalyst; however, its photocatalytic performance is constrained by its low surface area, wide band gap, and high electron–hole pair recombination rates. The objective of this study was to optimize the photocatalytic efficiency of TiO2 by impregnating it onto activated carbon derived from Senegalia mellifera biomass. The quantitative study involved synthesizing TiO2 using the precipitation technique and preparing AC through both chemical and physical activation methods. The prepared AC samples were impregnated with TiO2 NPs using the wet impregnation method. The physicochemical properties of the samples were examined using several characterization techniques, namely, FTIR, EDS, Raman, UV reflectance, STA, SEM, and BET. The photocatalytic efficiency of AC/TiO2 composites was evaluated through methyl orange degradation. The results showed significant improvement in photocatalytic performance when TiO2 was supported on AC. The modified photocatalyst exhibited enhanced surface area, thus increased active sites for photocatalysis, improving electron–hole separation and reducing recombination. The 50%CO2/AC-0.5TiO2 composite demonstrated superior photocatalytic activity under both UV and visible light irradiation. It showed 52.1% MO removal under visible light and 76.1% MO removal under UV light. The study concludes that biomass-derived AC/TiO2 composites present a promising, cost-effective and sustainable approach of enhancing photocatalytic activities.