Ultrasound-induced changes in mesostructure of amorphous iron (III) hydroxide xerogels: A small-angle neutron scattering study

Structure and thermal properties of iron III hydroxide xerogels obtained under high intensity ultrasonic treatment were studied by means of small-angle neutron scattering and heat-flux calorimetry. It was established that sonication affects the mesostructure of amorphous xerogels i.e., increase in their homogeneity, surface fractal dimension, and the sizes of aggregates of primary particles as opposed to the commonly accepted point of view that ultrasonic action cannot lead to notable changes in structure of powders, consisting of nanometer size particles. Ultrasonically induced structural changes in xerogels are evidently confirmed via their notably different reactivity at thermal decomposition under hydrothermal conditions.