Facile situ synthesis of C@SnO2/Sn@rGO hybrid nanosheets as high performance anode materials for lithium-ion batteries

Abstract

C@SnO2/Sn@rGO hybrid nanosheets are successfully synthesized via a situ method of SnO2@rGO precursors which are prepared by a facile hydrothermal reaction. The C@SnO2/Sn@rGO hybrid nanosheets are composed of carbon layer, rGO, SnO2 and reduction Sn which are generated in carbonization process of poly-dopamine layer. The amount of Sn in C@SnO2/Sn@rGO hybrid nanosheets can be adjusted by changing the carbonization time. The as prepared materials, especially the C@SnO2/Sn@rGO-1 sample, show superior cycling performance and electrochemical characteristics as lithium-ion batteries anode materials. In particular, the specific capacity of the C@SnO2/Sn@rGO-1 hybrid nanosheets electrode reaches 601.9 mAh/g at current density of 1 A/g even after 900 cycles. Furthermore, the C@SnO2/Sn@rGO-1 hybrid nanosheets electrode delivered ideal rate performance especially at such a high current density of 0.5 A/g, 1 A/g, 2 A/g and 5 A/g compared with the C@SnO2/Sn@rGO-2, C@SnO2/Sn@rGO-3 and SnO2@rGO electrodes. The nanosheets structure of C@SnO2/Sn@rGO-1 is beneficial to shorten the path of lithium-ion diffusion inside of the electrode and alleviate the volume expansion and contraction during cycling process. These results suggest that the prepared C@SnO2/Sn@rGO-1 hybrid nanosheets can be a promising anode material for the next generation of high-energy lithium-ion batteries.