Nanostructured hexagonal rare-earth orthoferrites (-RfeO, R = Sc, Y, Tb-Lu) are well known as a highly effective base for visible-light-driven heterojunction photocatalysts. However, their application is limited by metastability, leading to difficulties in synthesis due to the irreversible transformation to a stable orthorhombic structure. In this work, we report on a simple route to the stabilization of -YbFeO nanocrystals by the synthesis of multiphase nanocomposites with titania additives.
View Article and Find Full Text PDFSuperparamagnetic nanocrystals of gadolinium orthoferrite (GdFeO) with close to isometric morphology were successfully synthesized by heat treatment of gadolinium and iron(III) hydroxides obtained by direct co-precipitation with and without ultrasonic irradiation. The obtained samples were investigated by PXRD, low-temperature nitrogen adsorption-desorption isotherm measurements, HRTEM and VSM. It was established that ultrasonication during co-precipitation led to a decrease in the average size of GdFeO crystallites obtained after heat treatment by approximately 19%, an increase in their BET specific surface area by more than two times, a decrease in the degree of their aggregation by about five times and an improvement in their magnetic properties due to the increase in phase homogeneity.
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