Novel microwave initiated solid-state metathesis synthesis and characterization of lanthanide phosphates and vanadates, LMO4 (L = Y, La and M = V, P)

A novel solid-state metathesis (SSM) approach represented by the reaction (LCl3 + Na3VO4 → LVO4 + NaCl) (L = Y, La) is proposed to synthesize technologically important rare-earth phosphates and vanadates. The SSM reaction, driven in the forward direction is facilitated by the formation of high lattice energy by-product like NaCl. The structural, thermal, optical, and chemical properties of synthesized powders are determined by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC), and diffused reflectance (DR) spectra in the UV–vis range. The direct band gap of the synthesized materials was found out to be ∼3.5 eV for LaVO4, YVO4, YPO4 and ∼2.6 eV for LaPO4.

RECl3 + Na3VO4 → REVO4 + NaCl (RE = Y, La) Figure optionsDownload as PowerPoint slide