Enhanced hydrogen sorption on carbonaceous sorbents under electric field

Abstract The effect of an applied electric field on hydrogen physisorption isotherm on carbonaceous sorbents was studied. Distinctive sorption enhancement was obtained by applying a positive electrical potential of 2000 V to platinum-supported carbon samples. The phenomenon was ascribed to stronger interactions between hydrogen and the sorbent. Theoretical studies suggested that, the interaction between hydrogen and neutral carbon is primarily the electrostatic attraction between the π-bonds of the aromatic rings and the σ-bonds of H 2 , which is classified as van der Waals interaction and is weak. However, the interaction between electrically charged carbon and hydrogen might involve orbital interactions between hydrogen and carbon, an interaction stronger than van der Waals attraction. Experimental studies indicated that the presence of platinum would induce dissociation of hydrogen molecules in to hydrogen atoms. The easier accessibility of the atomic orbital might favor the electron transfer from the atomic hydrogen to charged carbon.