Multi-dimensional assembly of ZnO nanodots in the reticular carbon nanofibers for high-performance lithium-ion batteries

Due to the high theoretical specific capacity, abundant resources, easy availability, and environmental amicability, zinc oxide (ZnO) has been regarded as a promising alternative for lithium-ion battery anode. However, the further application of ZnO anode is still faced with great challenges such as huge volume transformation and intrinsic low conductivity. Herein, we propose a simple strategy for the preparation of ZnO/carbon clusters (∼50 nm) which are assembled with uniformly distributed ZnO nanodots (∼5 nm) in the three-dimensional carbon nanofibers (ZnO/CNFs) through an electrospinning and subsequent carbonization process using gallic acid-zinc coordination polymer (GAZ) as precursor. The multi-dimensional assembly of ZnO nanodots and reticular formation of conductive carbon network can effectively alleviate the volume change of ZnO anode during long-term cycling process and promote the fast transfer of electrolyte ions/electrons, greatly improving the rate and cycle performance. As a result, the ZnO/CNFs electrode exhibits excellent rate performance of 375.3 mAh g⁻¹ at 2 A g⁻¹ and long cycling stability with capacity retention of 92% over 600 cycles at 1 A g⁻¹. These features indicate that the systematic combination of electrospinning and metal-organic coordination polymers have significant promise for the construction of high-performance metal derivative anodes.