Journal
JOURNAL OF PHYSICAL CHEMISTRY C
Volume 118, Issue 15, Pages 7808-7820Publisher
AMER CHEMICAL SOC
DOI: 10.1021/jp500439n
Keywords
-
Funding
- Ministry of Science and Technology of China [2010CB631302]
- National Natural Science Foundation of China [U1201241, 51271078, 50925102]
- KLGHEI [KLB11003]
- Australian Research Council (ARC)
Ask authors/readers for more resources
Mg-based materials are promising candidates for high capacity hydrogen storage. However, their poor hydrogenation/dehydrogenation kinetics and high desorption temperature are the main obstacles to their applications. This paper reports a method for in situ formation of cycle stable CeH2.73-MgH2-Ni nanocomposites, from the hydrogenation of as-melt Mg80Ce18Ni2 alloy, with excellent hydrogen storage performance. The nanocomposites demonstrate reversible hydrogen storage capacity of more than 4.0 wt %, at a low desorption temperature with fast kinetics and long cycle life. The temperature for the full hydrogenation/dehydrogenation cycle of the composites is significantly decreased to 505 K, which is about 100 K lower than that for pure Mg. The hydrogen desorption activation energy is 63 +/- 3 kJ/mol H-2 for the composites, which is significantly lower than those of Mg3Ce alloy and pure Mg (104 +/- 7 and 158 +/- 2 kJ/mol H-2, respectively). X-ray diffraction and transmission electron microscopy have been used to reveal the mechanism that delivers this excellent cycle stability and fast hydriding/dehydriding kinetics. It is found that the hydriding/dehydriding process is catalyzed by the combination of in situ formed extremely fine CeH2/CeH2.73 and Ni to Mg/MgH2. In addition, this nanocomposite structure can effectively suppress Mg/MgH2 grain growth and enable the material to maintain its high performance for more than 500 hydrogenation dehydrogenation cycles.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available