Mg doped zinc manganese spinel ferrite: Fabrication and investigation of the structural and photocatalytic properties

To deal with environmental issues and wastewater treatments, the development and synthesis of highly effective semiconducting photocatalysts is a promising route. Sol-gel route was used for the preparation of zinc manganese ferrite (Zn0.6Mn0.4Fe2O4) and magnesium doped zinc manganese ferrite ((Zn0.6Mn0.4Mg0.06Fe2O4). However, the ultrasonication method was utilized for the fabrication of magnesium doped zinc manganese ferrite@CNTs nanocomposite (Zn0.6Mn0.4Mg0.06Fe2O4@CNTs). Characterization of materials was done via different techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Electrochemical impedance spectroscopy (EIS), UV-vis spectroscopy, and Mott-Schottky analysis. The crystallite size was calculated using the Debye-Scherrer formula. With the addition of magnesium in the zinc manganese ferrite, the band gap declines from 2.51 eV to 2.21 eV. The photocatalysis was carried out against the methyl orange (MO) and colorless effluent benzoic acid. By Zn0.6Mn0.4Mg0.06Fe2O4@CNTs, the % removal of MO was 92.22 % whereas for BO it was 34 %. Charge transfer resistance and flat band potential values for the nanocomposite were 1.12 Omega and 0.33 V respectively. The incorporation of CNTs into Zn0.6Mn0.4Mg0.06Fe2O4 accelerated the efficiency of photocatalysts, enhanced the migration of electrons, and suppressed the electron-hole pair recombination. Due to more surface area, the Zn0.6Mn0.4Mg0.06Fe2O4@CNTs showed the utmost results and acted as a highly proficient photocatalyst for the removal of organic effluents.