Stacked Cu2-xSe nanoplates with 2D nanochannels as high performance anode for lithium batteries.

Abstract Transition metal chalcogenides are considered as promising alternative materials for lithium-ion batteries owing to their relatively high theoretical capacity. However, poor cycle stability combined with low rate capacity still hinders their practical applications. In this work, the Cu-N chemical bonding directed the stacking Cu2−xSe nanoplates (DETA-Cu2−xSe) is developed to solve this issue. Such unique structure with small nanochannels can enhance the reactive site, facilitate the Li-ion transport as well as inhibit the structural collapse. Benefitting of these advantages, the DETA-Cu2−xSe exhibits high specific capacity, better rate capacity and long cyclability with the specific capacities of 565 mAh g−1 after 100 cycles at 200 mA g−1 and 368 mAh g−1 after 500 cycles at 5000 mA g−1. This novel DETA-Cu2−xSe structure with nanochannels is promising for next generation energy storage and the synthetic process can be extended to fabricate other transition metal chalcogenides with similar structure.