The electrochemical oxidation of ammonia over two types of SnO2-modified Pt (C-Pt/SnO2, SnO2-Pt/C) and Pt/C electrocatalysts was evaluated in alkaline aqueous solutions. Linear sweep voltammograms (LSVs) and chronoamperograms (CAs) were obtained in a 1 M KOH solution with 0.1 M NH3. The ammonia oxidation current achieved during the LSVs was in the order C-Pt/SnO2 > SnO2-Pt/C > Pt/C. In addition, the apparent activation energies for ammonia oxidation calculated from the CAs for C-Pt/SnO2, SnO2-Pt/C, and Pt/C at various temperatures were 52, 58, and 67 kJ mol (1), respectively. These results indicated that SnO2 activated the dehydrogenation of ammonia over Pt. Moreover, the I-V characteristics of an ammonia-fueled anion exchange membrane fuel cell with the SnO2-Pt/C anode clearly achieved a higher performance than with the Pt/C anode. (C)2015 Elsevier Ltd. All rights reserved.