Mesostructure of yttrium and aluminum basic salts coprecipitated from aqueous solutions under ultrasonic treatment

Abstract

The influence of ultrasonic treatment on the micro and mesostructures and fractal characteristics of amorphous powders of yttrium and aluminum basic salts (precursors for the synthesis of neodymium acti vated yttrium-aluminum garnet, Nd:YAG, which were coprecipitated from aqueous solutions by different precipitants, namely, aqueous solutions of ammonia and ammonium bicarbonate) is studied. It is established that ultrasonication applied during the precipitation of the aforementioned powders does not significantly change the structure of the obtained materials but always leads to the formation of structures with a less homogeneous nuclear density, i.e., a more developed surface area. Moreover, the ultrasound assisted precip itation of the hydroxocompounds by ammonium hydrocarbonate results in a certain increase in the surface fractal dimension and the degree of aggregation for mass fractal aggregates of particles.

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“…The value [5,130,147,196,230,351], aqueous suspensions of fullerene aggregates [311,362], polymer-surfactant mixtures [315], and others. The value ≈ 1.7 can be observed for aggregates in some magnetic colloids [91,308,367], proteins in mesoporous silicates [326], aluminum oxyhydroxide aerogel [236], and others.…”

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