The effect of surface modification of LaNi5 hydrogen storage alloy with CuCl on its electrochemical performances

The LaNi5 hydrogen storage alloy is modified by two steps: firstly, the alloy is treated with an aqueous solution of HF and KF.2H(2)O, then the as-obtained product reacts with CuCl in aqueous media at 30 degrees C, 50 degrees C and 70 degrees C respectively. XRD and SEM show that the samples obtained at 50 degrees C and 70 degrees C contain Cu and Cu2O, and their particles are evenly distributed on the alloy surface. The electrochemical properties of the alloy treated with 12.5 wt.% of the alloy at 50 degrees C are the best, which discharge 310 mA h g (1) at a current density of 50 mA g(-1), and 280 mA h g(-1) at 1000 mA g(-1), while the pristine alloy discharges only 290 mA h g(-1) at a current density of 50 mA g(-1), and 180 mA h g(-1) at 1000 mA g(-1). (C) 2014 Elsevier B.V. All rights reserved.