Single step, low-temperature synthesis of submicron-sized rare earth hexaborides

The first ever synthesis of submicron-sized rare earth hexaborides (RB6; R = La, Ce, Nd, Sm, Eu, and Gd) with a cubic morphology has been obtained by the single-step synthesis of the RAPET (reaction under autogenic pressure at elevated temperature) technique at a relatively low temperature of 900 degrees C using metal acetate precursors. The synthesized materials have been characterized for their structural (XRD, XPS, and Raman) and morphological (TEM, HRTEM, and FESEM) properties. The XRD pattern confirms the phase purity and the formation of a single phase compound of rare earth hexaborides. Raman spectra elucidate the active vibrational modes of the hexaborides. The TEM and FESEM images clearly show that the hexaborides are submicron in size with a cubic morphology. The SAED patterns reveal the single crystalline nature of the products.