Preparation And Na-Storage Properties Of Antimony-Based Anode Materials For Sodium-Ion Batteries

The excessive consumption of fossil energy promotes the development of renewable energy and the development of electrochemical energy storage.Lithium-ion battery?LIB?is the core of chemical energy storage.The low availability and unequal distribution of lithium resources have promoted the development and innovation of sodium-ion batteries?SIBs?.The composition and energy storage mechanism of SIBs and LIBs are similar,but the difference in charge carriers makes some difference between the two systems.The larger radius of sodium ion leads to the slow reaction kinetics of sodium-ion battery and the limited storage capacity of sodium ion.Therefore,the development of suitable anode materials is still the key to the development of sodium-ion batteries.Due to the influence of traditional LIBs,carbon material still plays an important role in SIBs,but its capacity is low.Alloy based materials are one of the most promising anode materials for sodium-ion batteries because of their high theoretical capacity.The large volume change during charging and discharging is the main obstacle to its application.Reasonable electrode construction is the key to solve the problem.In this paper,the electrode construction was carried out around the antimony based anode materials and the sodium storage performance was studied.The main contents are as follows:?1?In this paper,Sb was selected as the research object,carbon cloth?CC?,the carbonization product of biomass material commercial cotton cloth,was used as the substrate,and SbCl₃ nanoparticles were grown uniformly on CC by simple sublimation method.During annealing,SbCl₃ was transformed into Sb and Sb₂O₃ nanoparticles,the flexible Sb&Sb₂O₃/carbon cloth?Sb&Sb₂O₃/CC?anode electrode material was obtained.The material offers a good rate performance,more than twice the capacity of the original CC.At the current density of 100 mA g^-1,the specific capacity of Sb&Sb₂O₃/CC is 115.6 mA h g^-1.The improvement in the electrochemical performance of Sb&Sb₂O₃/CC is due to the modification of Sb&Sb₂O₃ nanoparticles to improve the capacity of CC,meanwhile,the electrode resistance of CC is reduced,and the ability of ion transport and electron conduction is improved.The hollow carbon fiber of CC alleviates the large volume variation of Sb&Sb₂O₃ nanoparticles.Sb&Sb₂O₃/CC also has smaller polarization and faster reaction kinetics,which greatly improves the sodium storage performance of the electrode material.?2?To further improve the cyclic stability of Sb&Sb₂O₃/CC,a carbon shell was coated.Sb&Sb₂O₃/CC was immersed in polyvinyl pyrrolidone?PVP?alcohol solution,after annealing treatment,the flexible of the PVP carbon shell Sb&Sb₂O₃@C/CC electrode materials was obtained.Sb&Sb₂O₃@C/CC demonstrated excellent electrochemical performance.At the current density of 600 mA g^-1,which can provide a specific capacity of 98.4 mA h g^-1.At 100 mA g^-1,it can provide a stable long cycle capacity.The internal soft CC substrate buffered the volume change of Sb and Sb₂O₃ nanoparticles,and the external PVP carbon shell prevented the falling off of Sb&Sb₂O₃ nanoparticles,which had significantly improved the electrochemical stability of the electrode.The electrochemical process of Sb&Sb₂O₃@C/CC is controlled by pseudocapacitive behavior and has fast reaction kinetics.This indicates that Sb&Sb₂O₃@C/CC electrode material has excellent sodium storage performance.?3?Antimony-based materials have been studied extensively,but the application of Sb₄O₅Cl₂ to sodium ion anode materials has been seldom reported.In this paper,the layered modification M-Sb₄O₅Cl₂ electrode material was synthesized by the solvent heat method and the facile chemical preintercalation method through temperature and KI addition volume exploration.Compared with Sb₄O₅Cl₂ electrode material,its rate performance and cycling performance are improved.At the current density of 100 mA g^-1,which provides a specific capacity of 41.8 mA h g^-1after 150 cycles,and the polarization decreases.The electrochemical behavior of M-Sb₄O₅Cl₂ is mainly controlled by diffusion behavior.The improvement of its electrochemical performance can be attributed to the addition of K and I elements,which enhances the layer spacing of M-Sb₄O₅Cl₂.It also provides a new method for improving the electrochemical performance of layered materials.