An experimental investigation on the poor hydrogen sorption properties of nano-structured LaNi5 prepared by ball-milling

作者：Joseph B^*; Schiavo B; Staiti G D'Ali; Sekhar B R

来源：International Journal of Hydrogen Energy, 2011, 36(13): 7914-7919.

DOI：10.1016/j.ijhydene.2011.01.090

• Hydrogen storage materials
• Nanostructuring
• Atomic disorder

Nano-structured LaNis hydrogen storage materials prepared by ball-milling is analysed using differential scanning calorimetry (DSC) and x-ray photoelectron spectroscopy (XPS). DSC results indicate a partial elimination of defects at 500 degrees C in a more efficient way for the short-time ball-milled powders compared to the long-time ball-milled ones. XPS results show almost no change in the core-level electronic structure for La and Ni of LaNis in the bulk and the nano-structured forms, but gives an indication that the self-restoring mechanism of the active surface observed in the bulk sample (Siegmann et al. Phys. Rev. Lett. 40, 972) may not be occurring in the nano-powders. Results from the X-ray diffraction and the local structural studies together with the above observations suggest that the reduced unit-cell volume and the enhanced atomic disorder in the nano-structured LaNis cause a larger energy barrier for the hydrogen sorption reactions of the long-time ballmilled samples.

• 出版日期2011-7