Resumen

GOMEZ-CUASPUD, Jairo A.  y  VALENCIA-RIOS, Jesús S.. CATALYTIC EVALUATION OF PEROVSKITE TYPE POLICATIÓNIC OXIDES OBTAINED BY POLYMERIZATION WITH CITRIC ACID. Rev.Colomb.Quim. [online]. 2009, vol.38, n.2, pp. 303-319. ISSN 0120-2804.

This paper describes the preparation of the La_0,75Sr_0,25Co_0,5Fe_0,5O₃ perovskite (LaSrCoFeO), using a wet chemical route, through polymerization with citric acid, to obtain materials for potential applications like electrodes in solid oxide fuel cells (SOFC). The solid was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and specific surface area by the BET method. This allows the determination of the formation of a perovskite type phase consistent with JCPDS registration: 089-1267. The texture and relief found are characteristic of the method of synthesis, giving the strong degree of roughness. The size of crystallites, calculated with the Scherrer Calculator software confirmed the presence of nanometric crystallites. The overall composition determined by X-ray microanalysis of energy dispersive (EDX) indicated a good correlation between the proposed and obtained. The assessment was carried out using the catalytic decomposition of hydrogen peroxide in alkaline medium, revealed that the reaction is pseudo first order with respect to peroxide, assuming that the mass of catalyst and concentration of the alkali do not affect the reaction rate, isotherms activity, apparent activation energy. In general activity observed corresponds to physical adsorption process.

Palabras llave : anodes; catalysis; coordination compounds; perovskites.