SnO_(2)/graphene nanocomposites have been fabricated by a simple chemical method.In the fabrication process,the control of surface charge causes echinoid-like SnO_(2)nanoparticles to be formed and uniformly decorated ...SnO_(2)/graphene nanocomposites have been fabricated by a simple chemical method.In the fabrication process,the control of surface charge causes echinoid-like SnO_(2)nanoparticles to be formed and uniformly decorated on the graphene.The electrostatic attraction between a graphene nanosheet(GNS)and the echinoid-like SnO_(2)particles under controlled pH creates a unique nanostructure in which extremely small SnO_(2)particles are uniformly dispersed on the GNS.The SnO_(2)/graphene nanocomposite has been shown to perform as a high capacity anode with good cycling behavior in lithium rechargeable batteries.The anode retained a reversible capacity of 634 mA·h·g^(–1)with a coulombic efficiency of 98%after 50 cycles.The high reversibility can be attributed to the mechanical buffering by the GNS against the large volume change of SnO_(2)during delithiation/lithiation reactions.Furthermore,the power capability is significantly enhanced due to the nanostructure,which enables facile electron transport through the GNS and fast delithiation/lithiation reactions within the echinoid-like nano-SnO_(2).The route suggested here for the fabrication of SnO_(2)/graphene hybrid materials is a simple economical route for the preparation of other graphene-based hybrid materials which can be employed in many different fields.展开更多
基金This work was supported by a grant from the Korea Science and Engineering Foundation(KOSEF)(WCU program,No.31-2008-000-10055-0)a grant from the National Research Foundation of Korea(No.NRF-2009-0094219)funded by the Ministry of Education and Science and Technology(MEST)the Energy Resources Technology R&D program(No.20092020100040)under the Ministry of Knowledge Economy.
文摘SnO_(2)/graphene nanocomposites have been fabricated by a simple chemical method.In the fabrication process,the control of surface charge causes echinoid-like SnO_(2)nanoparticles to be formed and uniformly decorated on the graphene.The electrostatic attraction between a graphene nanosheet(GNS)and the echinoid-like SnO_(2)particles under controlled pH creates a unique nanostructure in which extremely small SnO_(2)particles are uniformly dispersed on the GNS.The SnO_(2)/graphene nanocomposite has been shown to perform as a high capacity anode with good cycling behavior in lithium rechargeable batteries.The anode retained a reversible capacity of 634 mA·h·g^(–1)with a coulombic efficiency of 98%after 50 cycles.The high reversibility can be attributed to the mechanical buffering by the GNS against the large volume change of SnO_(2)during delithiation/lithiation reactions.Furthermore,the power capability is significantly enhanced due to the nanostructure,which enables facile electron transport through the GNS and fast delithiation/lithiation reactions within the echinoid-like nano-SnO_(2).The route suggested here for the fabrication of SnO_(2)/graphene hybrid materials is a simple economical route for the preparation of other graphene-based hybrid materials which can be employed in many different fields.
