Pt-shell-Au-core/C electrocatalyst with a controlled shell thickness and improved Pt utilization for fuel cell reactions

Nanoscale Pt-shell-Au-core/C with a controlled shell thickness was successfully synthesized based on a successive reduction strategy. With a Au core size of 4.8 mm, a complete Pt shell of thickness similar to 0.6 mm was formed at Pt/Au mole ratio 1:1. The complete coverage of Au core with Pt shell was suggested by various techniques including TEM, UV-vis and cyclic voltammetry. A higher specific activity compared to conventional Pt/C was demonstrated using the probe reaction of methanol electro-oxidation, proving the improved Pt utilization with this core-shell structure. (C) 2007 Elsevier B.V. All rights reserved.