Electrochemical hydrogen storage in TiC0.6, not in TiC0.9

We demonstrate that hydrogen can be electrochemically loaded, at room temperature, in the non-oxide ceramic TiC0.6. A capacity of 2.9 wt.% is easily reached, corresponding to the formula TiC0.6H1.6. We also demonstrate that hydrogen absorption was not possible in TiC0.9. This surprising result is interpreted in terms of absence of long-range ordered carbon vacancies, contrary to TiC0.6. It seems that TiC0.6 behaves like an intercalation compound for hydrogen.