The Model of Fractal Particles of Hydrated Zirconium Dioxide Based on Small-Angle Neutron Scattering Data
Parameters of the mesostructure of hydrated zirconium dioxide and their evolution at different stages of the heat treatment are determinedusing small-angle neutron scattering. It is shown that zirconia particles could form a mass fractal structure with fractal dimension Dv = 2.21at small annealing temperatures T = 100°C. The annealing of the sample at temperatures equal to or higher than 400°C leads to the formation of a “surface fractal” structure with the surface dimension Ds = 2.52. The concept of a surface fractal implies the existence of a dense nonfractal core—a cluster of zirconium dioxide nanoparticles with a constant density, and a shell with a fractal structure. A model for the evolution of the zirconium dioxide fractal structure with an increasing annealing temperature is proposed, which implies the formation of a surface fractal as a system consisting of a fractal shell on a dense core.