High surface area mesoporous nanocrystalline lanthanum phosphate nanorod through a sol–gel process – Effect of alcohol washing on a non-oxide gel

The present investigation is related to synthesis of high surface area lanthanum phosphate by an aqueous sol–gel process involving post gelation treatment by solvent exchange resulting in a soft agglomerated gel. Precursor sol, prepared from lanthanum nitrate through precipitation and peptization had an average particle size of 34 nm. The sol to gel transformation was carried out in presence of ammonia and resulted in a porous gel structure. Washing of the gel with different alcohols led to solvent exchange and subsequent drying resulted in the high surface area lanthanum phosphate. The surface area increased with the increase in boiling point of the alcohol used for washing. A surface area of 140 m2/g was obtained for the octanol washed lanthanum phosphate calcined at 400 °C.