Smart construction of Ti2Nb10O29 /carbon nanofiber core-shell composite arrays as anode materials for lithium-ion batteries

With high capacity and its safety, titanium niobium oxide (Ti 2 Nb 10 O 29 , TNO) has been reported as a potential anode for high power lithium ion batteries . However, insufficient diffusion coefficient of Lithium-ions and poor electronic conductivity for this electrode material significantly constrains its rate capability. To solve this issue, we propose a simple strategy to encapsulate Ti 2 Nb 10 O 29 in porous carbon nanofiber arrays (porous TNO/CNF) and to prepare heterogeneous Ti 2 Nb 10 O 29 /carbon nanofiber core-shell composite arrays (TNO NPs-CNF) using polyamic acid (PAA) as the polymer precursor. TNO NPs-CNF electrode exhibits significantly superior electrochemical performance (286 mA h g −1 at 10 C and 225 mA h g −1 at 20 C), much better than the TNO and porous TNO/CNF. For the electrode of porous TNO/CNF and TNO NPs-CNF, the omni-directional conducting networks of CNF skeleton greatly enhances electron transport of the whole electrode, reduces energy barrier of lithium ion transport, and maintains the structure’s stability.