Microstructure and hydrogen absorption/desorption properties of Mg24Y3M (M = Ni, Co, Cu, Al) alloys

作者：Yang, Tai; Li, Qiang^*; Liang, Chunyong^*; Wang, Xinghua; Xia, Chaoqun; Wang, Hongshui; Yin, Fuxing; Zhang, Yanghuan^*

来源：International Journal of Hydrogen Energy, 2018, 43(18): 8877-8887.

DOI：10.1016/j.ijhydene.2018.02.199

• Hydrogen storage
• Mg-based alloy
• Multiphase structure
• Kinetics
• Thermodynamics

Ternary alloys with the nominal composition of Mg24Y3M (M = Ni, Co, Cu, Al) have been fabricated by using vacuum induction melting method. Their microstructure and phase composition are characterized by using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The isothermal hydrogen absorption and desorption kinetics are measured by a Sievert's-type apparatus. The dehydrogenation behaviors of the full hydrogenated alloys are also analyzed by differential scanning calorimetry (DSC) method. Results show that each and every alloy has a distinct multiphase structure containing the main phase Mg24Y5 and some amount of Mg. Intermetallic compounds of YCo2 and Al2Y are detected in the M = Co and M = Al alloy, while long-period stacking ordered (LPSO) phase can be also observed in M = Ni and M = Cu alloy. The hydrogen absorption and desorption kinetics shows a decreased trend in the following order: (M = Ni) > (M = Al) > (M = Co) > (M = Cu). The M = Ni alloy has the best hydrogen storage performance among the investigated alloys. The dehydrogenation activation energy (E-a) of the M = Ni alloy decreases to 66 kJ/mol, and its decomposition peak temperature is also reduced to 313 degrees C. Moreover, the p-c-T (pressure-composition isotherms) curves of the studied alloys are also discussed.

• 出版日期2018-5-3
• 单位钢铁研究总院; 武汉科技大学; 河北工业大学