Crystallographic and electrochemical characteristics of icosahedral quasicrysyalline Ti45−xZr35−xNi17+2xCu3 (x = 0–8) powders

Ti45−xZr35−xNi17+2xCu3 (x = 0, 2, 4, 6 and 8) icosahedral quasicrystalline phase (I-phase) alloy powders are synthesized by mechanical alloying and subsequent annealing techniques, and the crystallographic and electrochemical characteristics are investigated. The alloy powders are I-phase, and the quasi-lattice constant decreases with increasing x value. The maximum discharge capacity of the I-phase alloy electrodes first increases and then decreases with increasing x value, and the Ti39Zr26Ni29Cu3 I-phase electrode exhibits the highest discharge capacity of 274 mAh g−1. The high-rate dischargeability at the discharge current density of 240 mA g−1 increases from 55.31% (x = 0) to 74.24% (x = 8). Cycling stability also increases with increasing x value. The improvement in electrochemical characteristics may be ascribed to the added nickel, which not only improves the electrochemical activity, but also makes the alloy more resistant to oxidation.