Highly Ultramicroporous Single-Walled Carbon Nanohorn Assemblies

Highly ultramicroporous single‐walled carbon nanohorns (see Figure), porosity‐designed by HNO3 treatment, show dramatically enhanced storage capacity of supercritical methane, which can be adsorbed into internal and interstitial spaces of the single‐wall carbon nanohorns. This enhanced storage capacity of methane may result from the developed ultramicroporosity, which can promote the adsorptivity of methane.