The initial adsorption process of benzene in double-walled carbon nanotubes studied by in situ solid-state NMR

Abstract

Information of adsorption and diffusion in nanoporous material is helpful to fundamentally understand nanocatalysis and gas sensors. In this work, the adsorption process of benzene in double-walled carbon nanotubes (DWNTs) at the very earliest stages was directly monitored for the first time by using in situ solid-state ¹³C NMR. The results indicate that benzenes in and out of DWNTs can be conveniently distinguished by ¹³C MAS NMR. The kinetics of the adsorption process was obtained by integrating the ¹³C peaks as a function of adsorption time. The kinetic could be interpreted with a model of opposing adsorption–desorption process and the kinetic curves could be satisfyingly fitted by an exponential function.