A VERSATILE COPRECIPITATION ROUTE FOR THE PREPARATION OF MIXED OXIDE POWDERS

Abstract

This paper describes the synthesis of mixed oxide powders by a new, versatile copreciprtation route, using a mixture of (MH₄)HCO₃ (NH₄) ₂CO₃, trieihylamine and formaline, in the presence of a soluble polymer such as polyvinyl alcohol (PVA). Each of the precipitating mixtures is chemically equivalent to one mole of triethylammonium carbonate. The composition of the mixed oxide system prepared is: MN₂O₄ (spinels; where M = Ni(ll). Cu(ll), Zn(ll), Co(ll) N = Felll), Cr(lll)) and RBa₂Cu₃O_x, (ceramic superconductors; where R = rare-earths). X-ray diflractometry (XRD), energy dispersive X-ray spectroscopy (EDXS) and scanning electron microscopy (SEM) observations are used for the characterization of the final products. The novelty of this route is its simplicity, cost effectiveness and the ability to produce fine, homogeneous, electronic grade materials.