Molecular dynamics and bio-synthesis of phoenix dactylifera mediated Mn 3 O 4 nanoparticles: Electrochemical application

The study reports computational and experimental synthesis of Mn 3 O 4 nanoparticles using extracts of Phoenix dactylifera otherwise known as date pits for electrochemical applications. The interaction of active compounds which are Gallic acid, L-Glutamic acid, and Sinapic acid contained in date pits serving as reducing agents with the Mn 3 O 4 nanoparticle is investigated using molecular dynamics (MD). The MD analysis enabled to guess the behaviour of the active compounds with the Mn 3 O 4 nanoparticles. Analysis of the density maps and Radial Distribution Function (RDF) showed that, L-Glutamic acid has the most hydrophilicity and the less affinity to interact with the Mn 3 O 4 nanoparticle compare to Gallic and Sinapic acids. By experimental analysis via UV-Vis absorbance, the presence of the active compounds is confirmed at absorbance peaks of 280 and 330 nm. Subsequently, the aqueous extracts obtained from date pits are used to bio-synthesized Mn 3 O 4 nanoparticles. Un-annealed Mn 3 O 4 nanoparticles are thermally oxidized in air for 2 h at 500 °C and 700 °C and subsequently characterized using Diffuse reflectance, XRD, FTIR, HRTEM, HRSEM, and EDS. As direct application, electrochemical properties of Mn 3 O 4 nanoparticles are evaluated using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). XRD analysis revealed plenty of diffraction peaks which are harmonized to Hausmannite Mn 3 O 4 phase. Meanwhile the crystallinity of samples with increasing annealing temperature was evaluated from SAED images characterized by the presence of scattered bright diffractions spots. The electrochemical analysis exhibited an excellent voltammetry response and good electrochemical performance making Hausmannite Mn 3 O 4 nanoplatelets a promising material for electrochemical applications.