Syntheses of perovskite oxides nanoparticles La1-xSrxMO3-δ (M = Co and Cu) as anode electrocatalyst for direct methanol fuel cell

Conventionally, noble metals such as Pt and Pt-Ru bimetallic system were utilized as electrocatalyst for methanol oxidation in acid and alkaline media. However, during the oxidation reaction, these noble metals are poisoned by the methanol oxidation intermediates, such as CO or COH species. Therefore, the utilization of electrochemically active conducting metal oxide (substituted perovskite oxide) may be a solution for avoiding such poisoning effect. In this study, the electrocatalytic activity of Sr substituted lanthanum metal oxide of La1-xSrxMO3-delta (where M = Co and Cu), were demonstrated towards direct methanol oxidation by cyclic voltammetry measurements. To further enhance the electrochemical activity, the perovskite electrocatalysts in this study was prepared in the nanoscale by the polymer modified sol-gel method using polyacrylic acid as a chelating agent. The strontium substituted lanthanum cobaltite and cuprate were synthesized in homogeneous nanosize particles of about 25-30 nm. The characterizations and electrocatalysts of the nanocrystalline perovskite were demonstrated by XRD, TGA, TEM, iodometric titration, and cyclic voltammetry. (C) 2004 Elsevier Ltd. All rights reserved.