title: Calcium-decorated carbyne networks as hydrogen storage media.
abstract: Among the carbon allotropes, carbyne chains appear outstandingly accessible for sorption and very light. Hydrogen adsorption on calcium-decorated carbyne chain was studied using ab initio density functional calculations. The estimation of surface area of carbyne gives the value four times larger than that of graphene, which makes carbyne attractive as a storage scaffold medium. Furthermore, calculations show that a Ca-decorated carbyne can adsorb up to 6 H(2) molecules per Ca atom with a binding energy of ∼0.2 eV, desirable for reversible storage, and the hydrogen storage capacity can exceed ∼8 wt %. Unlike recently reported transition metal-decorated carbon nanostructures, which suffer from the metal clustering diminishing the storage capacity, the clustering of Ca atoms on carbyne is energetically unfavorable. Thermodynamics of adsorption of H(2) molecules on the Ca atom was also investigated using equilibrium grand partition function.
authors.affiliation: Department of Mechanical Engineering and Materials Science, Rice University, Houston, Texas 77005, United States.
authors.forename: Pavel B
authors.initials: PB
authors.lastname: Sorokin
authors.forename: Hoonkyung
authors.initials: H
authors.lastname: Lee
authors.forename: Lyubov Yu
authors.initials: LY
authors.lastname: Antipina
authors.forename: Abhishek K
authors.initials: AK
authors.lastname: Singh
authors.forename: Boris I
authors.initials: BI
authors.lastname: Yakobson
mesh_terms: D000327:Adsorption; D002118:Calcium / Q000737:chemistry*; D002219:Carbamates / Q000737:chemistry*; D011211:Electric Power Supplies; D006859:Hydrogen / Q000737:chemistry*; D008958:Models, Molecular; D036103:Nanotechnology; D011789:Quantum Theory; D013499:Surface Properties
chemical_list: D002219:Carbamates; C004359:barban; D006859:Hydrogen; D002118:Calcium