Nano corundum - synthesis and use for filtration membranes, catalyst supports, wear prevention, and sensors

Abstract
Corundum nanoparticles (<100 nm) were prepd. by a powder and a sol/gel procedure (from Al(NO3)3/NH4OH and Al sec-butoxide/EtOAc/H2O, resp.). Adjustment of hydrolysis conditions and inoculation with diaspore yielded Al2O3 particles which transform to corundum at a temp. as low as 700-850.degree. thus preventing crystal growth and agglomeration during calcination. Filter membranes, coatings, and compact sintered products produced from the particles are characterized.