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Indexed by:期刊论文

Date of Publication:2015-05-01

Journal:PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES

Included Journals:SCIE、EI

Volume:69

Page Number:316-321

ISSN No.:1386-9477

Key Words:Graphene antidot lattices; Supercapacitors; Stability; Density of states; Diffusion

Abstract:Thermodynamic stabilities and electronic properties of graphene antidot lattices with hexagonal holes were examined using density functional theory calculations and several crucial factors related to the applications of supercapacitors were discussed. For the graphene antidot lattices with different hole sizes, the formation energy per edge length is about 0.50 similar to 0.60 eV/nm, which is comparable to that of graphene nanoribbon edges. Within a hole density of 10%, the graphene antidot lattices can maintain the excellent electronic properties of perfect graphene due to negligible intervalley scattering. Further increasing the hole density will open a band gap. Taking the potassium chloride (KCl) electrolyte as an example, we further investigated the diffusion behaviors of potassium (K) and chlorine (Cl) atoms through the graphene antidot lattices. It was shown that K and Cl atoms can go through the holes with nearly no barrier at an appropriate hole size of 0.54 nm, which gives an optimum pore diameter of similar to 0.86 nm. Therefore, the excellent graphene-like electronic properties and good penetrability for ions suggest promising applications of graphene antidot lattices in the field of supercapacitors. (C) 2015 Elsevier B.V. All rights reserved.