Structural, morphological, and electrochemical studies of Mg2SiO4-Pr6O11 nanocomposite for energy storage applications

Owing to not only the high demand in the development of new materials for the energy storage applications but also the high abundance of magnesium orthosilicate (Mg2SiO4) belonging to olivine group of minerals in Earth, magnesium orthosilicate (called as MOS) nanoparticle and magnesium orthosilicate-praseodymium oxide (Mg2SiO4-Pr6O11) (MOS-PO) nanocomposite have been chosen to explore mainly their electrochemical characteristics. The MOS nanoparticle and MOS-PO nanocomposite were synthesized using sol-gel method. The characterization techniques such as x-ray diffraction (XRD), Scanning Electron Microscopy (SEM), energy dispersive x-ray (EDX) spectroscopy, Zeta potential analyzer, and Cyclic Voltammetry (CV) were used to investigate the structural, morphological, and electrochemical properties of the prepared samples. Using Scherrer's equation, phase identification was performed for the samples of MOS nanoparticle and MOS-PO nanocomposite with crystallite sizes 43 nm and 52 nm, respectively. The respective average particle sizes of 39 nm and 50 nm were observed for MOS nanoparticle and MOS-PO nanocomposite, using SEM images, and these values along with the images revealed the formation of spherical nanoparticles along with some agglomerates. The Zeta potential of the samples was calculated to analyze the stability of the nanoparticles. The electrochemical characterization was performed using the sample coated Mg foil as the working electrode and 0.5 M of KOH solution as the electrolyte, with the help of cyclic voltametric technique. The CV analysis was conducted ranging from 1.5 to -1.5 V at various scan rates of 25, 50, 100, 200, and 300 mVs(-1). For MOS-PO nanocomposite, the maximum specific capacitance of 1812 Fg(-1) was observed at a scan rate of 25 mVs(-1). The results showed the possibility of the usage of MOS-PO nanocomposite material in the application of energy storage devices.