Aqueous sol-gel synthesis of lanthanum phosphate nano rods starting from lanthanum chloride precursor

Abstract

Aqueous sol-gel technique is reported for synthesizing nanosize, rod shaped lanthanum phosphate particles starting from lanthanum chloride, which is suitable for variety of applications such as machinable ceramics, thermal barrier coatings and luminescent materials. The phosphate particles are having rod like morphology having an overall size in the range 25-100 nm and with an average aspect ratio 4. The morphology is retained even after calcination at 800 A degrees C. The average crystallite size for the as prepared particles was calculated to be 8 nm using Scherrer equation applied on X-ray diffraction (XRD) data. The particles obtained were characterized using photon correlation spectroscopy (PCS), FT-IR spectroscopy, XRD and Electron Microscopy techniques (TEM and SEM). The phase stability was found using thermo gravimetric analysis. The surface wettability monitored using tensiometer through dynamic contact angle method indicated that lanthanum phosphate surface possesses considerable hydrophobic character.