1 School of Materials and Metallurgy, Inner Mongolia University of Science and Technology, Baotou 014010, Inner Mongolia, China 2 State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China 3 Department of Functional Material Research, Central Iron and Steel Research Institute, Beijing 100081, China
Effect of milling duration on hydrogen storage thermodynamics and kinetics of ball-milled Ce–Mg–Ni-based alloy powders
1 School of Materials and Metallurgy, Inner Mongolia University of Science and Technology, Baotou 014010, Inner Mongolia, China 2 State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China 3 Department of Functional Material Research, Central Iron and Steel Research Institute, Beijing 100081, China
摘要 To improve the hydrogen storage performance of CeMg12-type alloys, substituting the partial Mg with Ni in the alloy was conducted. The way to synthesize the aimed alloy powders was the mechanical milling method, by which the CeMg11Ni + x wt.% Ni (x = 100, 200) alloy powders with nanoctystalline and amorphous structure were obtained. The influence of the milling time and Ni content on the hydrogen storage properties of the alloys was discussed. The XRD and HRTEM were used to investigate the microstructures of the ball milling alloys. The hydrogenation/dehydrogenation dynamics were studied by Sievert instrument, and DSC which was link a H2 detector. The hydrogen desorption activation energies of the alloy hydrides were evaluated by Arrhenius and Kissinger means. From the results point of views, there is a little decline in the thermodynamic parameters (ΔH and ΔS) with the increase of Ni content. However, the alloys desorption and absorption dynamics are improved distinctly. What’s more, the variation of milling time results in a dramatic influence on the hydrogen storage performances of alloys. There are some maximum values of the hydrogen capacities correspond with the different milling time, which are 5.805 wt.% and 6.016 wt.% for the CeMg11Ni + x wt.% Ni (x = 100, 200) alloys, respectively. The kinetics tests suggest that the hydrogen absorption rates increase firstly, and then decrease with grinding time prolonged. The improvement of the gaseous hydrogen storage kinetics results from the decrease in the activation energy caused by the increase of Ni content and grinding time.
Abstract：To improve the hydrogen storage performance of CeMg12-type alloys, substituting the partial Mg with Ni in the alloy was conducted. The way to synthesize the aimed alloy powders was the mechanical milling method, by which the CeMg11Ni + x wt.% Ni (x = 100, 200) alloy powders with nanoctystalline and amorphous structure were obtained. The influence of the milling time and Ni content on the hydrogen storage properties of the alloys was discussed. The XRD and HRTEM were used to investigate the microstructures of the ball milling alloys. The hydrogenation/dehydrogenation dynamics were studied by Sievert instrument, and DSC which was link a H2 detector. The hydrogen desorption activation energies of the alloy hydrides were evaluated by Arrhenius and Kissinger means. From the results point of views, there is a little decline in the thermodynamic parameters (ΔH and ΔS) with the increase of Ni content. However, the alloys desorption and absorption dynamics are improved distinctly. What’s more, the variation of milling time results in a dramatic influence on the hydrogen storage performances of alloys. There are some maximum values of the hydrogen capacities correspond with the different milling time, which are 5.805 wt.% and 6.016 wt.% for the CeMg11Ni + x wt.% Ni (x = 100, 200) alloys, respectively. The kinetics tests suggest that the hydrogen absorption rates increase firstly, and then decrease with grinding time prolonged. The improvement of the gaseous hydrogen storage kinetics results from the decrease in the activation energy caused by the increase of Ni content and grinding time.
FENG Tian-Chen,XUN Hao,YU Xi-Shou, et al. Effect of milling duration on hydrogen storage thermodynamics and kinetics of ball-milled Ce–Mg–Ni-based alloy powders[J]. Journal of Iron and Steel Research International, 2018, 25(7): 746-754.
2018, Vol. 25 
