Diffuse reflectance spectroscopy analysis was performed on the synthesized catalysts to obtain the band gap energy values as determined from the Tauc plot. In the analysis, TiO2 is considered as an indirect semiconductor and the calculations are done on this basis. The formula used is where, Eg -band gap energy (eV),  -absorption coefficient, h -Planck's constant,  -frequency of light, A -constant, n = 4 (for indirect transition). The plot of (αh) The reduced band gap energy implies enhanced photocatalytic activity under solar or visible light irradiation, broadening the operational spectrum beyond UV light. Pure TiO₂, with a band gap of 3.2 eV, is predominantly active only under UV light, which constitutes a small fraction of the solar spectrum (~5%). In contrast, the lower band gap energies of the doped catalysts make them responsive to visible light, which forms a more substantial portion of the spectrum (~45%). This characteristic significantly increases the potential for these materials to be utilized in sunlightdriven photocatalytic applications, improving energy efficiency and environmental sustainability.