International Journal of Hydrogen Energy, Vol.42, No.27, 17149-17156, 2017
Synergetic effects of K, Ti and F on the hydrogen storage properties of the Li-N-H system
In this paper, the hydrogen storage properties of the LiNH2-LiH system doped with K2TiF6 were investigated and discussed. Interestingly, the hydrogen storage properties are significantly enhanced by introducing K2TiF6 into the LiNH2-LiH system. By doping 5 mol% K2TiF6 in the LiNH2-LiH system, we obtain the hydrogen desorption peak temperature (233 degrees C) at a heating rate of 10 degrees C min(-1), which is approximately 66 degrees C lower than that of the pristine LiNH2-LiH system. Moreover, the system begins to desorb H-2 at 75 degrees C, which is approximately 124 degrees C lower than in the pristine LiNH2-LiH system. The isothermal desorption kinetics at 250 degrees C and 300 degrees C clearly reflects the dramatically improved kinetic properties. Additionally, the reversibility of the LiNH2-LiH system can be drastically enhanced by adding K2TiF6. We propose that the dehydrogenation property of the K2TiF6-doped LiNH2-LiH sample is improved by the synergetic effects of K, Ti and F. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.