Inorganic nanotube composites based on polyaniline: Potential room-temperature hydrogen storage materials

Inorganic nanotubes as a support material for polyaniline were used for hydrogen storage. To this end, a solid-state preparation method has been developed for controlling the hydrogen storage capacity of these nanocomposites. The hydrogen storage capacities have measured at room temperature and at a low pressure of 0.5 MPa using the precise quadrupole quartz crystal microbalance technique in a chamber free of moisture. The optimum nanocomposite shows an enhanced hydrogen storage capacity of 0.78 wt.% with excellent reversibility when compared to less than 0.019 wt.% capacity of the pristine nanotubes and 0.05 wt.% of polyaniline. This large increase in the hydrogen capacity can be attributed to the chemisorption hydrogen uptake, which was enhanced by the sorption sites created through the milling process of polyaniline with the nanotubes. This is in addition to the hydrogen adsorption contribution by a controlled lumen size that is suitable for a maximum hydrogen adsorption through inserting polyaniline chains into the nanotubes.