Remarkable reactions of doped and Co-doped Co₃O₄ thin films synthesized by spray pyrolysis technique for enhanced catalytic degradation of methylene blue dye under sun light irradiation

Spray pyrolysis successfully synthesizes doped and co-doped thin films using the formula Al_xZn_0.06Co₃O₄ (x = 0.0, 0.01, 0.02, 0.03, 0.04, and 0.05). So, the prepared samples were examined for structural, surface morphology, optical, and photocatalytic properties using X-ray diffraction (XRD), scanning electron microscope (SEM) analyses, and ultraviolet–vsible spectrophotometer (UV–Vis). X-ray diffraction (XRD) analysis of all the samples verifies the presence of a single-phase spinel cubic structure, devoid of further heterogeneity or structural transition. The direct band gap E_g2 has decreased to 2.04 eV. Methylene blue (MB) degradation in sunshine shows that Al_xZn_0.06Co₃O₄ has substantially better photocatalytic activity than Zn_0.06Co₃O₄, with a maximum removal efficiency of 95.1% in 4 h. This contribution also presents a postulated mechanism for the photocatalytic activity of Zn_0.06Co₃O₄ thin films. Therefore, it is verified that the doped and co-doped Al_xZn_0.06Co₃O₄ thin films may be a cost-effective and environmentally safe catalyst for photocatalytic water purification. Consequently, it is verified that the doped and co-doped Al_xZn_0.06Co₃O₄ thin films may be a cost-effective and ecologically safe catalyst for photocatalytic water purification.