Core-shell structured SnSe@C microrod for Na-ion battery anode

摘要

The Sn Se nanoparticles encapsulated in the carbon nanofibers(Sn Se@C)with microrod morphology and core-shell structure are prepared by electrospinning and annealing process,and investigated as anode materials for sodium ion batteries.Benefiting from this unique structure,the Sn Se@C can deliver a reversible capacity of 283.8 m Ah g^(-1) after 500 cycles at a high current density of 1.0 A g^(-1).The sodium ion storage mechanisms of Sn Se are further characterized by ex-situ X-ray diffraction,high-resolution transmission electron microscope and selected area electron diffraction measurements.Besides,the excellent electrochemical performance of the electrodes is investigated by pseudocapacitance and in situ electrochemical impedance spectroscopy measurements.This work may provide a new avenue for synthesis of metal selenides with core-shell structure and a good idea for studying the kinetics process.