Factors affecting the electro-catalytic characteristics of Eu doped SnO2/Sb electrode

Different compositions of Eu doped electrodes were prepared by a pyrolysis method in order to investigate the effect of Eu on the electro-catalytic behavior of Ti-based SnO2/Sb electrodes. The electrodes were characterized by SEM, EDS, XRD and their degradation abilities were evaluated using phenol. The electrocatalytic performance of prepared electrodes was strongly influenced by the heat-treatment temperature and Eu doping content. A temperature of 750 degrees C and a Eu content of 2% provided optimal catalytic activity for the SnO2/Sb electrode. Phenol removal percentage was lowered by 13.2% compared to the control when higher Eu doping (5%) was applied due to the potential concentration of oxygen vacancies and the enrichment of Eu atoms on electrode surface. The unit cell of SnO2 expanded by about 2% after Eu doping due to the replacement of the smaller Sn4+ by larger Eu3+. The average size of the SnO2 grains on the electrode surface for the Eu doped samples ranged from 8 to 9 nm, which was smaller than that of the control, suggesting catalysis improvement since smaller grain sizes produced more active sites on the electrode surface. (C) 2010 Elsevier B.V. All rights reserved.