Dual-functional TiO₂ incorporated gum acacia hydrogel nanocomposites with enhanced photocatalytic and antibacterial...

Significant environmental problems are caused by dye pollution from industrial effluents, which calls for effective and long-lasting remedial techniques. In this work, we prepared TiO₂-incorporated gum acacia hydrogel nanocomposites (TiO₂-GA hydrogel nanocomposites) as an effective catalytic material for investigating the degradation of synthetic dyes Rhodamine-B (Rh-B) and Methyl Orange (MO) by free radical polymerization method. Structural, morphological, and physicochemical properties of the hydrogel nanocomposites were confirmed by different characterization methods. XPS analysis clearly confirmed the incorporation of TiO₂ into hydrogel network. Swelling studies showed that hydrogel nanocomposite exhibits maximum swelling percentage of 1540 % in basic medium at pH 10. The degradation experiments carried out by considering factors, such as pH, time of contact, initial dye concentration, and catalyst dosage under UV irradiation. The best degradation results were obtained at a dose of 30 mg (both Rh-B and MO) for 10 ppm dye concentration when observed for 30 min. Analysis of variance (ANOVA) when applied to Rh-B and MO dye Photocatalytic degradation percentage by TiO₂-GA hydrogel nanocomposites shows that all parameters have a significant effect on dye degradation and statistically significant difference exists between group means. The hydrogel nanocomposite achieved 100 % and 92 % degradation within a fixed time of 30 min following PFO kinetic model with rate constant of k = 0.1356 min^-1 and 0.1051 min^-1 for Rh-B and MO dyes respectively. The nanocomposite hydrogels exhibited appreciable antibacterial activities against both gram +ve bacterial strain (Bacillus subtilis) and gram -ve bacterial strains (Escherichia coli) with appreciable zone of inhibition (16 mm and 20 mm respectively) with 120 mg of nanocomposite sample and ANOVA analysis shows dose dependent activities of the nanocomposite hydrogels. Overall, the material exhibits excellent potential for multifunctional applications, offering an effective solution to both environmental and biomedical challenges.