A nano-thickness porous Pt0.9Pd0.1 alloy film with a greatly enhanced surface area were firstly synthesized at a glassy carbon electrode (GCE) using a facile cyclic voltammetry (CV) method. The atomic ratio of the alloy can be controlled by controlling the composition of the electrodeposition solution. We found that small amount of alloying Pd is an excellent catalytically enhancing agent for the Pt catalyst, and 10% Pd is the optimal. The structures of the Pt0.9Pd0.1 alloy film were characterized by FE-SEM, XPS, XRD and electrochemical techniques. It was found that the Pt0.9Pd0.1 film was in nanoporous structure and consisted of crystallites of 10.1 nm on average, leading to the modified electrode (Pt0.9Pd0.1/GCE) has an effective surface area as large as 790 times that of a corresponding bare Pt disk electrode. The Pt0.9Pd0.1/GCE exhibited significantly higher stability and catalytic activity for both of the methanol electro-oxidation reaction (MOR) and the oxygen electro-reduction reaction (ORR) than the correspondingly electrodeposited Pt modified GCE. The advantage can be attributed to the CV-prepared nano-porous structure on the electrode surface. This method and the prepared electrode can be expected to have promising applications in biosensors and fuel cells, etc. (C) 2007 Elsevier B.V. All rights reserved.