F127 Template on Pore Structure and Electrochemical Performances of Mesoporous SnO2

Mesoporous SnO2 was synthesized via a hydrothermal process using tin chloride (SnCl4 center dot 5H(2)O) and urea ((NH2)(2)CO) as raw materials, with a block polyether F127(EO106-PO70-EO106) as a template. The analysis results (XRD, TEM, BET, etc) show that the amount of F127 has significant influence on pore structure of mesoporous SnO2. With increasing dosage of F127, specific surface area and pore volume of the mesoporous SnO2 increase with pore size distribution relatively broad. The results of the electrochemical tests indicate that existence of mesopores not only provide the path for deinsertion and insertion of Li+, but also buffer the huge volume expansion of tin dioxide, which consequently improves the electrochemical performances of mesoporous SnO2 as an anode material. When the amount of F127 is 6.0 g, the as-prepared 6F-SnO2 with a BET specific surface area of 124 m(2)/g and average pore size of 4.94 nm, displays optimal cycle performance and rate performance which the reversible capacity of the 6F-SnO2 maintains 434 mAh/g at 60 mA/g after 30 cycles. In addition, the cyclic voltammetric test reveals that the reversible reduction of partial Li2O with high activity can provide additional reversible capacity.