Nanopowders of metallic oxides prepared by the hydrolytic route with starch stabilization and biological abetment

Sn, Sn-Sb, Ti, Zr, Fe, Ce and In oxides are prepared as nanometric powders by the hydrolytic route, starting from their ordinary salts or alkoxides, in the presence of 5% w/v starch as a non-ionic stabilizer of crystallization nuclei versus coalescence and flocculation. The starch can be degraded by alpha-amylase to soluble glucosidic oligomers, which may further be degraded by yeast to CO2 and ethanol. The nanoparticle features of prepared oxides result from experimental evidence based on X-ray diffractometry, transmission electron microscopy, differential thermal analysis/thermogravimetry coupled to mass spectrometry, specific surface area and porosity of samples obtained by curing in the 80-600 degrees C interval.