Structural, DFT, vibrational spectroscopic, thermal, electrical and magnetic characterizations of hydrothermally grown CoCO3 microcrystals.

The minerals such as the CoCO₃ can be utilized for the fabrication of lithium-grafted batteries and for a variety of food applications. In this study, we have successfully synthesized Cobalt carbonate crystals (CoCO₃) using hydrothermal synthesis method. The synthesized micro-crystals consist of hexagonal structure symmetry. The XRD shows the single-phase hexagonal (R-3c) crystal with lattice constants a = 4.661 Å, b = 4.661 Å, and c = 14.96 Å. EDAX spectroscopy analysis confirms the presence of all the elements of sample. FE-SEM analysis suggests nearly rod-shaped crystals with ~ 29 µm average crystalline size. The Fourier Transform Infrared spectrum suggested existence of O–H, C–O etc. bonding. The TGA is carried out to study the thermal stability. The dielectric relaxation is well studied over large angular frequency range. Complex impedance spectrum of the synthesized microcrystals consists of single semi-circular arc due to the presence of grain only. The magnetic study has suggested paramagnetic nature of the sample. The theoretical study such as the density function theory has been carried out using the Quantum ESPRESSO. A reasonably good agreement is observed between experimentally obtained data and DFT data for optimized structures. [ABSTRACT FROM AUTHOR]