Relations Between Microstructure of Mg/Cu Super-Laminates and Kinetics of Hydrogen Absorption/Desorption

摘要

Super-laminates have been attracting attention since co-authors Ueda et al. reported that Mg/Cu super-laminates showed reversible hydrogenation and dehydrogenation at 473K. The Mg/Cu super-laminates were prepared by a repetitive fold and roll method. Initial activation at 573K led the super-laminates to absorb hydrogen at 473K. TEM observations of micro/nano-structures in the super-laminates were performed in order to clarify the process of hydrogenation and dehydrogenation at 473K, The as-rolled Mg/Cu super-laminates have laminated structures in size of sub-micrometer thickness composed of Mg and Cu layers with dense lattice defects. The super-laminates after initial activation keep laminated structure and have uniformly distributed pores with a sub-micrometer diameter. It is considered that these micro/nano-structures of Mg/Cu super-laminates lead to lower dehydrogenation temperature and better kinetics, which would contribute to achieve high performance hydrogen storage materials.