Increase in thermal stability induced by organic coatings on nanoparticles

Based on Lindemann melting criterion and atomic thermal vibration suppression, a thermodynamic model is developed to reveal the mechanism behind the stability of nanoparticles of the smaller size capped with organic molecules. A quantitative description about the increase of the melting temperature of the nanoparticles, due to the interface interaction with organic coatings, is provided by determining the atomic vibrational displacement parameter alpha. Furthermore, the minimum crystalline nucleus size of the nanoparticles is calculated by combining Turnbull's classical nuclear theory with the size effect of Gibbs free energy.