Polypyrrole/SnO2@SiO2 as anode materials with improved lithium storage performance

Polypyrrole (PPy)-coated tin oxide and silica oxide composite nanomaterials are synthesized by hydrothermal method and electrochemical in situ polymerization. Herein, the effect of PPy contents on the structure and properties of PPy/SnO2@SiO2 nanocomposites is investigated. With the increase of the pyrrole monomer content, the thickness of the cladding layer of PPy/SnO2@SiO2 core-shell structure increases gradually. And the results indicate that the sample containing 28 wt% PPy exhibits the stable structure of composite and high initial capacity. Moreover, the first discharge capacity reaches 3750 mAh g(-1) and its specific capacity can still maintain 676 mAh g(-1) after 100 cycles. Owing to this core-shell structure nanomaterial which provides more stable intercalation-deintercalation of lithium channels and sites, PPy coating can inhibit the volumetric expansion of the SnO2 nanospheres (NPs) electrode effectively. Consideration of the remarkable performance and high initial capacity, PPy/SnO2@SiO2 composite is of keen interest for a potential lithium ion battery anode material.