Antimony-Based Intermetallic Alloy Anodes

An antimony containing intermetallic alloy compound consisting of molybdenum and antimony dispersed in an amorphous carbon matrix was developed using a high-energy mechanical milling technique (119). This material was used as the anode for a sodium-ion battery 

The structure and morphology of the as-prepared material were characterized using XRD and TEM. The ex-situ XRD measurement confirmed the formation of a NasSb phase during the sodiation. The electrochemical performance of the so-prepared MosSby-C composite demonstrated a stable cyclability up to 40 cycles at a current rate of 100 mAg.  

When a fluoroethylene carbonate additive was introduced into the electrolyte, the MosSbz-C anodes exhibited a longer cyclic life with a capacity retention of aroimd 90% at 100 cycles, as well as a superior rate-cyclic performance corresponding to a capacity retention of more than 70% at 10,000 mA g.  

This enhanced electrochemical performance could be ascribed to the formation of a stable solid electrolyte interphase layer, smaller charge transfer resistance, and better dispersion of Mo3Sb7 nanoparticles in the carbon matrix (119). 

An important strategy to design suitable electrolyte systems has been shown that makes the desirable interfacial structure to allow the reversible sodiation and desodiation of SrqPs anodes (120). A remarkable improvement in the electrochemical performance of SrqPs anodes for sodium-ion batteries can be achieved by the combination of fluoroethylene carbonate with tris(trimethylsilyl) phosphite. 

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