Journal of Materials Research

Articles

Dehydrogenation/rehydrogenation mechanism in aluminum destabilized lithium borohydride

Xuebin Yua1 c1, Guanglin Xiaa2, Zaiping Guo and Huakun Liua3

a1 Department of Materials Science, Fudan University, Shanghai 200433, China; Institute for Superconducting and Electronic Materials, University of Wollongong, NSW 2522, Australia; and CSIRO National Hydrogen Materials Alliance, CSIRO Energy Centre, Mayfield West, NSW 2304, Australia

a2 Department of Materials Science, Fudan University, Shanghai 200433, China

a3 Institute for Superconducting and Electronic Materials, University of Wollongong, NSW 2522, Australia; and CSIRO National Hydrogen Materials Alliance, CSIRO Energy Centre, Mayfield West, NSW 2304, Australia

Abstract

LiBH4/Al mixtures with various mol ratios were prepared by ball milling. The hydrogen storage properties of the mixtures were evaluated by differential scanning calorimetry/thermogravimetry analyses coupled with mass spectrometry measurements. The phase compositions and chemical state of elements for the LiBH4/Al mixtures before and after hydrogen desorption and absorption reactions were assessed via powder x-ray diffraction, infrared spectroscopy, and x-ray photoelectron spectroscopy. Dehydrogenation results revealed that LiBH4 could react with Al to form AlB2 and AlLi compounds with a two-step decomposition, resulting in improved dehydrogenation. The rehydrogenation experiments were investigated at 600 °C with various H2 pressure. It was found that intermediate hydride was formed firstly at a low H2 pressure of 30 atm, while LiBH4 could be reformed completely after increasing the pressure to 100 atm. Absorption/desorption cycle results showed that the dehydrogenation temperature increased and the hydrogen capacity degraded with the increase of cycle numbers.

(Received August 12 2008)

(Accepted November 11 2008)

Key Words:

  • Energy storage;
  • Hydrogenation

Correspondence:

c1 Address all correspondence to this author. e-mail: yuxuebin@fudan.edu.cn

0Comments