Bioinspired Synthesis of Transition Metal‐Enhanced Co₃O₄ Using Mangifera indica Leaves for Photocatalytic and Energy Storage Applications

The topic of wastewater remediation has been extensively discussed in recent years, and one of the main pollutants has been dyes. One of the promising techniques for dye degradation is photocatalysis. A novel transition metal Fe with different percentage (15%, 20%, 25%) doped Co3O4 was prepared employing a novel green process using Mangifera Indica leaf extract.The structural, morphological, optical, and electrical properties of doped catalyst was studied by XRD, FTIR, FE‐SEM, HR‐TEM, PL, CV, EIS, TGA, XPS, UV‐DRS, and BET analysis.By doping the Fe metal on the surface of Co3O4 resulting increase in surface area with improving charge carriers separation and lower the band gap energy. The photocatalytic activity was studied by degrading BG dye under solar light.25% Fe doped cobalt oxide having band gap energy 2.1 eV showed maximum degradation efficiency of 96% at pH 8 on 30 ppm dye concentration with 30 mg catalyst under 90min.The radical trapping experiment showed the vital role of hydroxyl and superoxide radical in degradation mechanism. By doping Fe atoms the efficiency of the host is increased which will be the most promising candidate for the photocatalytic dye degradation applications. The material presents a strong possibility for use in super capacitor applications due to its increased current density and lower on set potential. This study highlights green synthesis of Fe‐doped Co3O4 nanoparticles using Mangifera indica leaf extract. Different characterization techniques reveal the excellent structural, optical, electrical properties with enhanced surface area, charge separation.The Fe‐doped Co3O4 achieves 96% photocatalytic degradation of Brilliant green dye under solar light and shows potential for supercapacitor applications due to its improved current density and lower onset potential.