title: Ultrahigh Capacity Due to Multi-Electron Conversion Reaction in Reduced Graphene Oxide-Wrapped MoO2 Porous Nanobelts.
abstract: Multivalent transition metal oxides (MOx ) containing redox centers which can theoretically accept more than one electron have been suggested as promising anode materials for high-performance lithium ion batteries (LIBs). The Li-storage mechanism of these oxides is suggested to involve an unusual conversion reaction leading to the formation of metallic nanograins and Li2 O; however, a full-scale conversion reaction is seldom observed in molybdenum dioxide (MoO2 ) at room temperature due to slow kinetics. Herein, a full-scale multi-electron conversion reaction, leading to a high reversible capacity (974 mA h g(-1) charging capacity at 60 mA g(-1) ) in LIBs, is realized in a hybrid consisting of reduced graphene oxide (rGO) sheet-wrapped MoO2 porous nanobelts (rGO/MoO2 NBs). The rGO wrapping layers stabilize the nanophase transition in MoO2 and alleviate volume swing effects during lithiation/delithiation processes. This enables the hybrid to exhibit great cycle stability (tested to around 1900 cycles) and ultrafast rate capability (tested up to 50 A g(-1) ).
authors.affiliation: Department of Chemistry, National University of Singapore, 117543, Singapore.|NUS Graduate School for Integrative Sciences & Engineering (NGS), Centre for Life Sciences (CeLS), #05-01, 28 Medical Drive, 117456, Singapore.
authors.forename: Wei
authors.initials: W
authors.lastname: Tang
authors.affiliation: Department of Chemistry, National University of Singapore, 117543, Singapore.
authors.forename: Cheng Xin
authors.initials: CX
authors.lastname: Peng
authors.affiliation: Department of Chemistry, National University of Singapore, 117543, Singapore.|NUS Graduate School for Integrative Sciences & Engineering (NGS), Centre for Life Sciences (CeLS), #05-01, 28 Medical Drive, 117456, Singapore.
authors.forename: Chang Tai
authors.initials: CT
authors.lastname: Nai
authors.affiliation: Department of Chemistry, National University of Singapore, 117543, Singapore.
authors.forename: Jie
authors.initials: J
authors.lastname: Su
authors.affiliation: Department of Chemistry, National University of Singapore, 117543, Singapore.
authors.forename: Yan Peng
authors.initials: YP
authors.lastname: Liu
authors.affiliation: Department of Physics, National University of Singapore, 117542, Singapore.
authors.forename: M V Venkatashamy
authors.initials: MV
authors.lastname: Reddy
authors.affiliation: Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), 117602, Singapore.
authors.forename: Ming
authors.initials: M
authors.lastname: Lin
authors.affiliation: Department of Chemistry, National University of Singapore, 117543, Singapore.
authors.forename: Kian Ping
authors.initials: KP
authors.lastname: Loh
keywords: MoO2 porous nanobelts; batteries; high capacity; rGO scaffolds; reduced graphene oxide