Platinum (Pt) black electrode was fabricated by electrolytic deposition for oxidation of ammonia. The electrocatalytic activity of the fabricated platinum black was characterized by cyclic voltammetry and atomic force microscopy observation. Pt black electrocatalyst enhances significantly the electro-oxidation of ammonia. The increased catalytic activity of Pt black electrode is attributable to both an increased effective surface area and the enhanced electron transfer reaction. However, the latter is predominant throughout the ammonia oxidation processes. The electrolytic depositing parameters affect the electrocatalytic activity of Pt black electrode. In particular, there is an optimal depositing potential to maximize the electrocatalytic activity. With the increasing depositing time and elevated bath temperature, the electrocatalytic activity of Pt black electrode increases continuously in this work. (c) 2007 Elsevier B.V. All rights reserved.