화학공학소재연구정보센터
International Journal of Hydrogen Energy, Vol.41, No.41, 18582-18591, 2016
Electrochemical study of the reversible hydrogen storage in CeTi2Cr4Ni5-based metal hydride alloys
A novel PuNi3-type intermetallic compound CeTi(2)NisCr(4) is elaborated by mechanical alloying and investigated as a negative electrode material for nickel-metal hydride (Ni-MH) batteries. The synthesis reaction is performed from pure ABs-type CeNis and AB(2)-type TiCr2 intermetallic precursors. The crystallographic parameters of prepared compounds are calculated by the Rietveld refinement of X-ray diffraction (XRD) patterns for powders ball milled between 2 and 20 h. The highest content of CeTi(2)NisCr(4) phase is 51 wt.% in powder elaborated after 8 h of milling time. The reversible hydrogenation of CeTi(2)NisCr(4)-based electrodes is characterized electrochemically in the presence of alkaline electrolyte at room temperature. The maximum discharge capacity is 205 mAh g(-1) and the average capacity retention is 84% upon 30 charge/discharge cycles, demonstrating the suitable electrochemical behavior of CeTi2Ni5Cr4. Competitive hydrogen diffusion rates are also obtained in the range of (1.9-10.5) 10-10 cm(2) s(-1). (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.