Characterization of Cosub(x)Znsub(7-x)Sbsub(2)Osub(12) spinel obtained by pechini method

Abstract

Oxides with spinel structure have been studied for many decades. The reason is a wide variety of application as pigments, refractories and also as a model structure to studies that evaluate the relative stability of ions in octahedral and tetrahedral sites. Zincantimonium spinels (Zn7Sb2012) were synthesized by Pechini method, substituting the cation Zn2+by Coe+, according to the stoichiometry Co xZn7_,Sb2O17 (x = 0 — 7). Thermal characterization of the powders, after pyrolysis, was done using TG/DTA analysis, being observed different mass losses, according to the cobalt amount in the resin. Powders were calcined at 600 to 1000 °C and characterized by XRD, BET and IV spectroscopy. Maximum cristalinity was obtained at 1000 °C. Materials with x = 5 — 7 presented a secondary phase (Co, Zn)Sb206. Using infrared analysis, the possible sites were Zn2+ , Co2+and Sb2+are located in the net were inferred.