Speaker: Dr. Zhen-Kun Tang, Beijing Computational Science Research Center

Abstract: Graphene and monolayer MoS2 have received significant attentions because of their potential applications in electro-catalysts, transistors, photoluminescence, and rechargeable Li batteries. In general, the performances are closely related the surface areas and surface active sites. Although the two-dimensional (2D) layered structures exhibit large surface areas, while they usually recover to the multilayer because of the vdW interactions.Here, a novel three-dimensional hybrid structure of graphene-MoS2 (3DGM) is proposed by the first principle calculations. The 3DGM can effectively avoid the aggregation as usually occurs in the 2D materials. Compared with the 2D layered materials, 3DGM materials not only own the large surface area, but also exhibit the high conductivity. First principles molecular dynamics simulations show that the 3DGM structures are thermodynamically stable at room temperature. Interestingly, the electronic structure of 3DGM are closely related to the configuration of joint zone. For example, the 3DGM with odd-layer thickness MoS2 nanoribbon building blocks are semiconductor with a small band gap of 0.01-0.25 eV, while the 3DGM with even-layer thickness MoS2 nanoribbon building blocks exhibit metallic features. More importantly, the 3DGM with zigzag MoS2 nanoribbon not only own the large surface area and effectively avoid the aggregation between the different nanoribbons, but also can remarkably enhance Li adsorption interaction, thus the 3DGM have the great potential as high performance lithium ion battery cathodes.

 Date&Time: March 20, 2015 (Friday), 14:30 - 15:30
Location: A102 Conference Hall