Electrochemical synthesis and lithium storage properties of three-dimensional porous Sn-Co alloy/CNT composite

Three-dimensional (3-D) porous copper with stable pore structure is prepared by electroless plating. 3-D porous Sn-Co alloy/carbon nanotube (CNT) composite is synthesized by electrodeposition using 3-D porous copper as the substrate. The scanning electron microscope results indicate that 3-D porous Sn-Co alloy/CNT composite contains a large amount of interconnected pores with the diameter size of similar to 3 mu m. Upon cycling, the pore structure gradually disappears, but no serious exfoliation appears due to porous structure and reinforcement by CNT. The charge/discharge results demonstrate that the 3-D porous Sn-Co alloy/CNT composite electrode delivers high first reversible specific capacity of 490 mAh g(-1), and remains 441 mAh g(-1) after 60 cycles tested at different current densities. Even at the current density of 3,200 mA g(-1), the reversible specific capacity remains 319 mAh g(-1), which is 65 % of the first specific capacity cycled at the current density of 100 mA g(-1).