The reversible hydrogen storage of graphitic carbon nitride (g-C3N4) nanotubes at room temperature was first studied through experimental methods in this work and was compared to multiwalled carbon nanotubes (MWCNT), bulk g-C3N4, and g-C3N4 nanosheets. Compared with MWCNT which had a similar specific surface area around 60 m2/g, g-C3N4 nanotubes had a higher room temperature hydrogen storage capacity up from 0.46 wt% for MWCNT to 0.78 wt%. This value for the g-C3N4 nanotubes was also higher than the hydrogen storage capacity of bulk g-C3N4 (0.51 wt%) and g-C3N4 nanosheets (0.73 wt%), even though g-C3N4 nanosheets had the highest specific surface area of 161 m2/g. Temperature programming desorption (TPD) was applied to study the desorption behaviours and it was found that chemisorption contributed to the relative high storage capacity of g-C3N4 nanotubes.
- Energy storage
- Graphitic carbon nitride (g-CN) nanotubes
- Hydrogen adsorption/desorption
- Isosteric heat of adsorption