Hydrogen adsorption on graphene sheets and nonporous graphitized thermal carbon black at low surface coverage

Behavior of hydrogen adsorption on nonporous carbon based materials was comparatively studied for selection of an efficient carrier for catalytic metals. Graphene sheets (GS) and graphitized thermal carbon black, which respectively has a specific surface area about 220 m2/g and 36 m2/g, were selected for adsorption equilibrium testes within temperature-pressure range from 77 K-87 K and 0-1 kPa. Henry law constants were employed to calculate the second virial constants and the limit isosteric heat of adsorption. The Weeks, Chandler and Andersen (WCA) perturbing scheme and the fundamental measure theory (FMT) were used to determine the interaction energy between solid atoms and hydrogen molecules. Adsorption potential well was determined by linear interpolation based on the Boltzmann distribution approximation. It shows that the potential well between hydrogen molecules and the GS, BP280 is respectively about 33.55 K and 31.97 K, suggesting that the bonding energy between the GS and hydrogen molecules is larger than that on carbon black.