Preparation of graphite supported Li-N-H hydrogen storage material from Li-graphite intercalation compound and their unique hydrogen release property

摘要

A highly dispersed Li-N-H hydrogen storage material supported on graphite was prepared from a Li-graphite intercalation compound with ammonia, and their hydrogen release property was investigated. In addition, the changes of the chemical state of the lithium species responsible for hydrogen storage/release were investigated using ~7Li NMR and XRD. Those spectral analyses revealed that the graphite supported Li-N-H hydrogen storage material released hydrogen at lower temperature than in the absence of graphite support and Li_3N was directly formed in one single step without going through the formation of Li_2NH. Also we found that durability to hydrogen storage/release cycles was improved in the presence of graphite support.