The characterization of Co xZn7-xSb2O12 spinel obtained by the pechini method

• Autor(a) principal: Gouveia,Deiby Santos
• Data de Publicação: 2005
• Outros Autores: Rosenhaim,Raul, Lima,Severino Jackson Guedes, Longo,Elson, Souza,Antonio Gouveia de, Santos,Iêda Maria Garcia dos
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Materials research (São Carlos. Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392005000200023
• topic: spinel; Zn7Sb2O12; pechini; cobalt

Oxides with spinel structures have been studied for many decades as they have been used in a variety of applications like pigments and refractories. They have also been used as a model structure to evaluate the relative stability of ions in octahedral and tetrahedral sites. Zinc- antimony spinels (Zn7Sb2O12) were synthesized by the Pechini method and the cation Zn2+ was substituted by Co2+, taking into consideration the stoichiometry of Co xZn7-xSb2O12 (x = 0 - 7). Characterization of the thermal properties of pyrolyzed powders was carried out with a TG/DTA analyzer, and mass losses were determined as a function of the cobalt content in the resin. The powders were calcined at temperatures in the range 600 to 1000 °C and characterized by XRD, BET and IR spectroscopy. Maximum cristalinity was obtained in powders calcined at 1000 °C. Materials with x = 5 - 7 revealed the presence of a secondary phase (Co, Zn)Sb2O6. Infrared analysis facilitated in the determination of the possible sites of Zn2+, Co2+ and Sb2+ ions in the lattice.