High Mobility and High Storage Capacity of Lithium in sp–sp² Hybridized Carbon Network: The Case of Graphyne

Abstract

We have carried out first-principles calculations to explore the energetics and dynamics of Li in graphyne, a novel carbon allotrope consisting of spÀsp 2 hybridized carbon atoms, relevant for anode lithium intercalation in rechargeable Li-ion batteries. In contrast to graphite where Li diffusion is confined in the interlayer space (in-plane diffusion), the unique atomic arrangement and electronic structures enable both inplane and out-plane diffusion of Li ions in graphyne with moderate barriers, 0.53À0.57 eV. The highest Li intercalation density in graphyne can be LiC 4 , exceeding the up limit of LiC 6 in the commonly used graphite. The high lithium mobility and high storage capacity make graphyne a promising candidate for the anode material in battery applications.

Adsorption and growth of palladium clusters on graphdiyne

“…1, was considered to simulate the substrate. The optimized lattice constant is 9.7 Å, in good agreement with other DFT calculations [33][34][35] . Due to the diversity in the hybridization of the carbon-carbon bonds in the −C≡C−C≡C− chains in graphdiyne, the bond lengths along the chain are different: 1.39, 1.23, 1.33, 1.23, and 1.39 Å, aligned from one carbon hexagon to the nearest carbon of an adjacent hexagon.…”

Fluorographynes: Stability, structural and electronic properties

“…They are considered as possible promising materials for nanoelectronics, for hydrogen storage, as membranes (for example, for hydrogen separation from syngas -as an alternative for nanomeshy graphene), for energy storage applications or as candidates for the anode material in batteries [20][21][22][23][24][25][26]. Thus, the tuning of the properties of these materials should be critical for their further applications.…”

The roles of π electrons in the electronic structures and optical properties of graphyne

“…In contrast to graphene with identical  bindings, graphyne has three types of  bindings, C(sp 2 )-C(sp 2 ), C(sp)-C(sp 2 ), and C(sp)-C(sp), as shown in Figure 1. A number of theoretical calculations on graphyne monolayer [13,[16][17][18][19] and graphyne-related nanomaterials [20][21][22] have been performed to reveal their unique properties and potential applications. First-principles calculations showed that single-layered graphyne is semiconducting with a small direct band gap of ~0.5 eV at M point [16].…”