Sintered Carbon Nanomaterials: Structural Change and Adsorption Properties

Abstract

Abstract Porous powdered carbon nanomaterials [carbon nanotubes (CNT) and carbon nanoshells (CNS)] were compacted using spark plasma sintering (SPS) technique. High resolution transmission electron microscopy (HRTEM) and SEM images demonstrate the structural change: the increase of density and thickness of nanoshells stack, formation of interparticle bonds between nanotubes. Surface properties of original and sintered materials were studied by liquid nitrogen sorption and compared to the characteristics for real vapors sorption. The data collected for water, ethanol, acetonitrile and benzene show both physical adsorption and chemisorption. The mean pore diameter distribution calculated from nitrogen adsorption by density functional theory (DFT) approach shows the reduction of total pore volume in CNS pellet while for CNT pellet total pore volume does not differ dramatically from those for non-compacted samples. The isosteric heats of sorption for all chosed vapors were calculated.