Investigation of Induction Time and Nucleation Kinetics in Sodium Nitrate Nanoparticles: The Role of Super-Saturation and Surfactant Additives

This study investigates sodium nitrate nanoparticles' nucleation and induction time in the presence of Sodium Dodecyl Sulfate (SDS) as a surfactant during reactive crystallization. The primary objective was to assess how varying super-saturation levels and SDS addition influence the induction time and nucleation process. Experiments were conducted at 25°C, and the induction time was measured for different sodium nitrate concentrations and surfactant amounts. The results revealed that increasing super-saturation reduced induction time, aligning with the classical nucleation theory. Additionally, the presence of SDS altered the nucleation process, with its effect being most pronounced at higher super-saturation levels. While SDS did not prevent nitrate adsorption onto the crystal surface, it accelerated the process by forming complexes within the solution. These complexes, larger and slowerto penetrate, reducing the nucleation speed. At lower concentrations, the solution exhibited faster penetration and shorter induction times. The study demonstrates that SDS and super-saturation significantly impact induction time, with a positive correlation between nucleation rate and super-saturation. This research provides new insights into the nucleation behavior of sodium nitrate nanoparticles and the role of surfactants in the crystallization process, contributing to the optimization of nanoparticle production methods.