2022 Volume 1 Issue 3 Pages 123-135
Various types of vapor adsorption (water, methanol, ethanol, dichloromethane, and n-hexane) were examined on templated nanoporous carbons comprising 1–2 graphene layers, e.g., microporous zeolite-templated carbon (ZTC), mesoporous carbon mesosponge (CMS), and graphene mesosponge (GMS). Conventional nanoporous carbon materials are used as references. Although water-vapor adsorption is unique owing to the repulsion between H2O molecules and hydrophobic carbon, organic-vapor adsorption follows a typical physisorption mechanism. Graphene-based nanoporous materials exhibit an evident degree of adsorption-induced expansion based on their extraordinary softness, except in the case of inferior water-vapor adsorption on mesoporous CMS and GMS. CMS exhibits a considerable degree of adsorption-induced expansion and can achieve high adsorption capacities up to 4.25–4.76 cm3 g−1 for organic vapors, demonstrating its feasibility as a high-capacity adsorbent. The adsorption isotherms of ZTC at 278 and 298 K for n-hexane overlap well, which is advantageous for a new heat pump working with a force-induced phase transition. Moreover, this study helps predict the ease of organic-vapor adsorption based on the product of the surface tension and molar volume.
