Structure and electrochemical hydrogen storage properties of A2B-type Ti-Zr-Ni alloys

Elemental substitution of part Ti by Zr has been carried out for Ti2Ni alloy to form Ti2-xZrxNi (x = 0, 0.2, 0.4) alloys. Mechanical milling and subsequent heat treatment have been used to prepare non-equilibrium Ti-Zr-Ni alloys. The effects of Zr addition on the structure and discharge properties of Ti2Ni alloy were investigated. The addition of Zr could enhance the discharge capacity of the non-equilibrium Ti2Ni alloy at electrolyte temperatures of 313 and 333 K. For instance, the non-equlibrium Ti1.6Zr0.4Ni alloy had a stable discharge capacity of about 210 mAh/g at 313 K. However, the protective surface layer formed during heat treatment was destroyed at a high electrolyte temperature of 333 K, and thus a severe capacity loss during cycling. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.