Design and Multifunctional Performance of Zinc-Doped Magnesium Ferrite Nanostructures for Enhanced Electrochemical, Sensing and Photocatalytical Applications

In this study, zinc-doped magnesium ferrite (Znx-Mg1−xFe2O4) nanoparticles were synthesized using a facile combustion method and investigated for their electrochemical sensing and photocatalytic applications. The structural, morphological, and optical properties of the synthesized nanoparticles were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDAX), Fourier-transform infrared spectroscopy (FTIR), Energy band gap (Eg) and UV-Vis spectroscopy. The synthesized Zn–MgFe2O4 nanoparticles exhibited crystallite sizes ranging from 18.7 to 27.9 nm with an optical band gap of 1.86–1.89 eV. The catalyst achieved degradation efficiencies of 78% for Eriochrome Black T and 85% for Methyl Orange within 120 min, while the electrochemical sensor exhibited excellent linearity toward HgCl2 detection (R2 = 0.99664), demonstrating the multifunctional capability of the synthesized nanostructure. The synergistic effects of Zn doping contributed to enhanced electrical conductivity, catalytic activity, and structural stability. The novelty of this work lies in the development of combustion-synthesized Zn–MgFe2O4 nanoparticles as a multifunctional material capable of simultaneously achieving efficient photocatalytic degradation of organic dyes and sensitive electrochemical detection of mercury chloride using a simple and scalable synthesis route. These findings demonstrate that Zn–MgFe2O4 nanoparticles hold significant potential for integrated environmental remediation and electrochemical sensing applications.