The characterization analysis results obtained from diffuse reflectance spectroscopy (DRS) were utilized to plot the graph of (E*A) 2 versus energy for the synthesized photocatalysts-B-TiO2, Ag-TiO2, and Ce-TiO2. This plot is essential for determining the band gap energies of the photocatalysts, as it provides a clear representation of the relationship between the energy of the incident light and the corresponding absorption characteristics.