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Enhanced Absorption and Diffusion Properties of Lithium on B,N,V_C-decorated Graphene.

ABSTRACT: Systematic first-principles calculations were performed to investigate the adsorption and diffusion of Li on different graphene layers with B/N-doping and/or C-vacancy, so as to understand why doping heteroatoms in graphene anode could significantly improve the performance of lithium-ion batteries. We found that the formation of single or double carbon vacancies in graphene are critical for the adsorption of Li atoms. While the N-doping facilitates the formation of vacancies, it introduces over binding issue and hinders the Li diffusion. The presence of B takes the excessive electrons from Li and N and reduces the energy barrier of Li diffusion on substrates. We perceive that these clear insights are crucial for the further development of graphene based anode materials for lithium-ion batteries.

SUBMITTER: Jin M

PROVIDER: S-EPMC5126578 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Enhanced Absorption and Diffusion Properties of Lithium on B,N,VC-decorated Graphene.

Jin Mengting M Yu L C LC Shi W M WM Deng J G JG Zhang Y N YN

Scientific reports 20161129

Systematic first-principles calculations were performed to investigate the adsorption and diffusion of Li on different graphene layers with B/N-doping and/or C-vacancy, so as to understand why doping heteroatoms in graphene anode could significantly improve the performance of lithium-ion batteries. We found that the formation of single or double carbon vacancies in graphene are critical for the adsorption of Li atoms. While the N-doping facilitates the formation of vacancies, it introduces over ...[more]

PMID: 27897202

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