Graphitic nano-fibers - A candidate for hydrogen storage.
With the XRK 900 reactor chamber in-situ X-ray diffraction studies of catalysts as well as of graphitic nano-fibers were performed.
After CCVD preparation of the nano-fibers, they were treated with hydrogen at 5 bar and 600 °C.
The amount of hydrogen adsorbed on the fibers was found to be approx. 1 mass%. The hydrogen storage leads to an increase of the d002 lattice distance of 0.03 Å due to hydrogen incorporation between the graphite layers. The lattice expansion could only be observed when the synthesized fibers did not have any contact with air.
Thus the XRK 900 is an essential analytical tool for in-situ XRD investigations at elevated temperatures and pressures.
The correlation between the structural changes of the nano-fibers and the amount of adsorbed hydrogen is the subject of further studies.