Bifunctional activities of phosphorus doped MnO2 with activated carbon from Manilkara zapota peel bio-waste for supercapacitor and photocatalytic degradation of organic dye

The contributions of phosphorus, activated carbon (AC), and their composite species have resulted in significant improvements in electrochemical and photocatalytic degradation performance. Phosphorus and activated carbon are suitably dispersed and make good contact with MnO 2 . KOH chemical activation was used to synthesize activated carbon from Manilkara zapota peel. The hydrothermal approach was used to synthesize MnO 2 and P-MnO 2 /AC nanoparticles in this study. The materials structure and bonding nature were analyzed using X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The morphological characterizations (SEM, FE-SEM, and TEM) revealed that the AC covered the α-MnO 2 nanorods. The bandgap values were determined using UV–visible diffuse reflectance spectroscopy (UV–Vis DRS). MnO 2 , PM 1, 3, and 5 bandgap values of P-MnO 2 /AC are 2.48 eV, 1.99 eV, 1.76 eV, and 1.62 eV, respectively. The PM 5 of P-MnO 2 /AC electrode material has a high specific capacitance of 522.22 Fg −1 at 0.5 Ag −1 current density and excellent cyclic stability of 95.4% preserved after 3000 charge–discharge (GCD) cycles at 6 Ag −1 . P-MnO 2 /AC had the greatest photocatalytic degradation capability for MB dye, with an excellent degradation efficiency of 95.22%. Similarly, the photocatalytic mechanism of performance increase was addressed.