Hydrothermal Synthesis and Photocatalytic Efficiency of Turmeric Leaves Biochar/TiO2 Composite for Photooxidation of Congo Red Dye

Abstract

The hydrothermal synthesis of an eco-friendly photocatalyst using turmeric leaves biochar (TLB) and titanium dioxide nanoparticle composite has been reported for the degradation of Congo Red (CR) dye. The synthesized composite was characterized using various analytical techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) analysis, Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), confirming its structural and morphological attributes that ensured the uniform dispersion and intimate contact between TLB and TiO₂ particles. The degradation performance of the TLB/TiO₂ composite was examined by using UV light irradiation as a catalyst. The results demonstrated that the TLB/TiO₂ composite exhibited superior photocatalytic activity compared to pristine TiO₂, attributed to the enhanced light absorption, improved charge separation, and increased surface area provided by the biochar. The degradation kinetics followed a pseudo-first-order model, with a significant reduction in the dye concentration within a short time frame. The eco-friendly nature, cost-effectiveness, and high photocatalytic efficiency of the TLB/TiO₂ composite highlight its potential application in wastewater treatment, thus providing a novel approach to valorize agricultural waste into functional materials for sustainable environmental technologies.