Qian Zhang1, Peide Han1, Jun Mei2,3. 1. College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China. 2. School of Chemistry and Physics, Queensland University of Technology, Brisbane, QLD 4000, Australia. 3. Centre for Materials Science, Queensland University of Technology, Brisbane, QLD 4000, Australia.
Abstract
Hematite (α-Fe2O3) is a promising electrode material for cost-effective lithium-ion batteries (LIBs), and the coupling with graphene to form Gr/α-Fe2O3 heterostructures can make full use of the merits of each individual component, thus promoting the lithium storage properties. However, the influences of the termination of α-Fe2O3 on the interfacial structure and electrochemical performance have rarely studied. In this work, three typical Gr/α-Fe2O3 interfacial systems, namely, single Fe-terminated (Fe-O3-Fe-R), double Fe-terminated (Fe-Fe-O3-R), and O-terminated (O3-Fe-Fe-R) structures, were fully investigated through first-principle calculation. The results demonstrated that the Gr/Fe-O3-Fe-R system possessed good structural stability, high adsorption ability, low volume expansion, as well as a minor diffusion barrier along the interface. Meanwhile, investigations on active heteroatoms (e.g., B, N, O, S, and P) used to modify Gr were further conducted to critically analyze interfacial structure and Li storage behavior. It was demonstrated that structural stability and interfacial capability were promoted. Furthermore, N-doped Gr/Fe-O3-Fe-R changed the diffusion pathway and made it easy to achieve free diffusion for the Li atom and to shorten the diffusion pathway.
class="Chemical">Hematite (α-class="Chemical">n class="Chemical">Fe2O3) is a promising electrode material for cost-effective lithium-ion batteries (LIBs), and the coupling with graphene to form Gr/α-Fe2O3 heterostructures can make full use of the merits of each individual component, thus promoting the lithium storage properties. However, the influences of the termination of α-Fe2O3 on the interfacial structure and electrochemical performance have rarely studied. In this work, three typical Gr/α-Fe2O3 interfacial systems, namely, single Fe-terminated (Fe-O3-Fe-R), double Fe-terminated (Fe-Fe-O3-R), and O-terminated (O3-Fe-Fe-R) structures, were fully investigated through first-principle calculation. The results demonstrated that the Gr/Fe-O3-Fe-R system possessed good structural stability, high adsorption ability, low volume expansion, as well as a minor diffusion barrier along the interface. Meanwhile, investigations on active heteroatoms (e.g., B, N, O, S, and P) used to modify Gr were further conducted to critically analyze interfacial structure and Li storage behavior. It was demonstrated that structural stability and interfacial capability were promoted. Furthermore, N-dopedGr/Fe-O3-Fe-R changed the diffusion pathway and made it easy to achieve free diffusion for the Li atom and to shorten the diffusion pathway.
Entities:
Keywords:
first principle; heteroatoms; interface; lithium storage; α-Fe2O3
Authors: Antonino Salvatore Aricò; Peter Bruce; Bruno Scrosati; Jean-Marie Tarascon; Walter van Schalkwijk Journal: Nat Mater Date: 2005-05 Impact factor: 43.841
Authors: C Lemire; S Bertarione; A Zecchina; D Scarano; A Chaka; S Shaikhutdinov; H-J Freund Journal: Phys Rev Lett Date: 2005-04-26 Impact factor: 9.161