Solubility of nanoparticles: nonextensive thermodynamics approach

Abstract

We show in this study that the concepts of nonextensive thermodynamics, introduced ina previous work, can be used to express the variations of the solubility ofnanoparticles and porous materials according to their mass by power laws, withoutthe need to resort to fractal dimensions. This results in the demonstration ofthe Ostwald–Freundlich relation. Our approach is based on a thermodynamicdescription involving the introduction in the internal energy expression of an extensity,χ.χ is an Euler’s function of the particle mass with a homogeneity degree,m, which can beother than one; m is the thermodynamic dimension of the system. We use this approach to simulate variousbehaviours, and show that an increase in solubility can be either higher or lower than thatenvisaged by the Ostwald–Freundlich relation.