Kinetic energy of neon atoms adsorbed on activated carbon

Direct measurements of the kinetic energy of Ne atoms adsorbed on activated carbon (AC) at submonolayer coverage, is reported. The electronvolt spectrometer of the ISIS neutron source that utilizes the neutron Compton scattering technique, was employed. The specific adsorption area of the AC was ∼3000 m2/g. The momentum distribution of adsorbed Neon was measured at 12 K. The kinetic energy of Ne was found to be 66.3±6.2 K, and is much higher than that of solid neon, at the same temperature, being 45.8±4.8 K. This result is considered to be an evidence for the occurrence of a confinement effect of Ne atoms within the pores of the AC. The result was also used for deducing the average pore size of the AC adsorber assumed to have slit shaped pores.