Thermal investigation of NbSe2 nanoparticles synthesized through a temperature-dependent sonochemical method

Abstract

Due to their unique size-dependent properties, transition metal di-chalcogenide nanoparticles are trending in research for their potential to revolutionize next-generation electronics, energy storage, and catalytic processes. This study addresses the effect of temperature when synthesizing NbSe₂ nanoparticles via the sonochemical method at three different temperatures, room temperature (R.T.), 70 °C, and 100 °C. Energy Dispersive X-ray Analysis (EDAX) confirmed the high purity of NbSe₂, with the sample synthesized at 70 °C, displaying the accurate stoichiometric ratio. X-ray diffraction (XRD) analysis revealed that all samples maintained the hexagonal phase of NbSe₂, with 70 °C exhibiting superior crystallinity due to their crystallite size, lowest dislocation density, and minimal internal strain. Thermogravimetric analysis (TGA) and differential thermogravimetric (DTG) analyses, demonstrated that the sample synthesized at 70 °C had the highest thermal stability, with the lowest total weight loss and most consistent mass loss behavior. Kinetic parameters were evaluated using the Kissinger–Akahira–Sunose (KAS) and Flynn–Wall–Ozawa (FWO) methods, determining activation energy (E_a), pre-exponential factor (A), change in activation enthalpy (ΔH*), change in activation entropy (ΔS*), and Gibbs free energy change (ΔG*). Also, the sample synthesized at 70 °C exhibited the highest E_a, indicating superior thermal stability and favorable reaction kinetics. The findings underscore the significant impact of synthesis temperature on the structural and thermal properties of NbSe₂ nanoparticles, with the sample synthesized at 70 °C demonstrating optimal characteristics. This study provides valuable insights into temperature-dependent synthesis and the thermal behavior of NbSe₂ nanoparticles, highlighting their potential in various technological applications.