Using a combination of two fuels, the auto-combustion method was used to synthesize pure TiO2 and doped TiO2 with different concentrations of iron(III) (Fe) and manganese(II) (Mn) (1, 3, 5, and 7 mol%). The as-prepared materials were characterized using different techniques, including thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), and high-resolution transmission electron microscopy (HR-TEM). The XRD results showed that both the TiO2 and almost-doped TiO2 samples had the anatase phase, indicating the crystalline nature of all the as-prepared nanomaterials. Crystal violet decolorization under UV irradiation was used to assess the photocatalytic activity of the samples as they were initially manufactured. The findings showed that, compared to other dopant concentrations, TiO2 with a dopant concentration of 5% Fe and 7% Mn showed the highest degradation rates (95.93% and 96.3%, respectively) at 100 and 70 min, with pseudo first rate constants of k = 2.91 x10-2 and 4.8 x 10-2 min-1, respectively. It was found that superoxide radicals and hydroxyl radicals were the main reactive species responsible for dye degradation.