Rapid Synthesis of Citric Acid Coated Manganese Ferrite Nanoparticles: Electrochemical Supercapacitor Applications

To manufacture nanoscale materials with high surface density, achieving average pore size and volume requires energy-intensive and time-consuming operations. We present a straightforward rapid, and quick approach for synthesizing citric acid coated manganese ferrite (MnFe<sub>2</sub>O<sub>4</sub>) nanoparticles through chemical co-precipitation with 1 M NaOH as an oxidative solution. The citric acid coated MnFe<sub>2</sub>O<sub>4 </sub>nanoparticles were studied by powder X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. The powder X-ray diffraction results confirm the spinel structure of MnFe<sub>2</sub>O<sub>4 </sub>based on face centred cubic lattice parameters. The Fourier transform infrared spectroscopy results confirm the vibrational modes of citric acid coated MnFe<sub>2</sub>O<sub>4</sub>. The scanning electron microscope results of the as synthesised citric acid coated MnFe<sub>2</sub>O<sub>4 </sub>product had a spherical form with an average diameter of 20 nm. The electrochemical properties of MnFe<sub>2</sub>O<sub>4</sub> nanoparticles were studied using cyclic voltammetry, charge-discharge, and electrochemical impedance spectroscopy using 1M NaOH as a electrolyte. Citric-acid coated MnFe<sub>2</sub>O<sub>4</sub> nanoparticles shows pseudo-capacitance behaviour properties and delivers a specific capacitance value of about 381 F g<sup>-1 </sup>at 1 A g<sup>-1</sup> specific current with 15% retention rate at high specific currents. The specific capacitance remained at 92% after 10,000 cycles at a specific current of 2 A g<sup>−1</sup> which is clearly showed.