Mechanochemical synthesis of rare earth orthovanadates from R_2O_3 (R = rare earth elements) and V_2O_5 powders

摘要

Lanthanum oxide (La_2O_3) and vanadium pentoxide (V_2O_5) mixture was milled by planetary ball mill to investigate the formation of lanthanum orthovanadate (LaVO_4) by mechanochemical reaction. The formation of LaVO_4 during milling was monitored by a suite of analytical methods including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and inductivity coupled plasma-atomic emission spectrometry (ICP-AES). The LaVO_4 powder prepared by 4h milling consists of particles with size up to several microns and has specific surface area of 9.70 m~2/g. The mechanochemical method can be applied to the synthesis of other rare earth orthovanadates (RVO_4; R = Y, Nd, Sm, Gd, Dy and Er). RVO_4 prepared by this method has both zircon-type low pressure phase and scheelite-type high pressure one.