Rational Design of NiCoO2@SnO2 Heterostructure Attached on Amorphous Carbon Nanotubes with Improved Lithium Storage Properties.

It still remains very challenging to design proper heterostructures to enhance the electrochemical performance of transition metal oxide-based anode materials for lithium-ion batteries. Here, we synthesized the NiCoO2 nanosheets@SnO2 layer heterostructure supported by amorphous carbon nanotubes (ACNTs) which is derived from polymeric nanotubes (PNTs) by a stepwise method. The inner SnO2 layer not only provides a considerable capacity contribution but also produces the extra Li2O to promote the charge process of NiCoO2 and thus results in a rising cycling performance. Combining with the contribution of ACNTs backbone and ultrathin NiCoO2 nanosheets, the specific capacities of these one-dimensional nanostructures show an interesting gradually increasing trend even after 100 cycles at 400 mA g(-1) with a final result of 1166 mAh g(-1). This approach can be an efficient general strategy for the preparation of mixed-metal-oxide one-dimensional nanostructures and this innovative design of hybrid electrode materials provides a promising approach for batteries with improved electrochemical performance.