Synthesis And Electrochemical Properties Of Antimony Based Nanocomposites

Sodium-ion batteries（SIBs）,as a promising alternative to lithium ion batteries（LIBs）,have attracted increasing attention in view of the natural abundance and environmental benignity of sodium resources.Compared to LIBs,searching for appropriate SIB electrode materials that can effectively host larger Na⁺is a main challenge.Unremitting efforts have been devoted to discover new anode materials with high performance for SIBs.The Sb-based materials（Sb and Sb based alloy,oxides and sulfides,composites）have demonstrated high specific capacity.However,the batteries employing Sb-based alloy materials normally suffer from severe capacity fading owing to the huge volume expansion of the structure of metal Sb（up to 390%）in the charge-discharge process.In order to improve the electrochemical properties of the materials,a series of Sb-based composites were synthesized by various facile method.The main contents and achievements are as follows:（1）We report the synthesis of Sb/CNT nanocomposite by a facile one-pot refluxing method.The prepared Sb/CNT nanocomposite was employed as anode material for SIBs and showed high energy storage property with initial discharge capacity of 628.6 m Ah g^-1 at 0.1A g^-1.The material shows excellent rate capability and cycle stability,which is superior to Sb-only counterpart.（2）We present a facile two-step hydrothermal process for the synthesis of Sb₂S₃/MoS₂heterostructure to enhance the electrochemical properties of SIBs.In the constructed architectures,Sb₂S₃ nanorods were coated with MoS₂ nanosheets to form core-shell structure with homogenous heterointerface,which can improve ion diffusion kinetics and boost electronic conductivity.Compared with individual Sb₂S₃and MoS₂,the SIBs using Sb₂S₃/MoS₂heterostructure as anodes exhibit significantly improved specific capacity,outstanding cycling stability and rate performance.（3）Based on the as-synthesised Sb₂S₃/MoS₂ heterostructure,hydrothermal method are coated with polydopamine（PDA）to form Sb₂S₃/MoS₂@PDA core-shell nanorods.Afterwards,the as-prepared Sb₂S₃/MoS₂@PDA nanorods are heated in Ar atmosphere,finally leading to the formation of unique Sb/MoS₂@C nanotubes.The remarkable electrochemical performance results from the unique nanostructure.The carbon and MoS₂shell not only prevents the aggregation of Sb active materials but also protects the Sb against direct contact with the electrolyte.The facile synthesis approach and unique nanostructure design may be extended to other alloy materials for high-performance sodium-ion batteries.