The core-shell mesoporous titanium dioxide with in-situ nitrogen doped carbon as the anode for high performance lithium-ion battery

The core-shell hierarchical mesoporous titanium dioxides with situ nitrogen dopen carbon and the stable architecture are synthesized by a feasible route, basing on the sol-gel, freeze-drying and calcination process. Nitrogen doped carbon is synergistically compounded with nano-TiO2 to fabricate the hybrid composite (C-N@MP-TiO2), which has high surface area of 318 m(2) g(-1) and large average pore size of 6.8 nm. This corresponding anode consisted of the hybrid composite exhibits superior specific capacity, rate capability, and long cycling stability. Also, the initial discharge capacity is up to 360 mAh g(-1) at the current density of 0.1 A g(-1) with the good capacity retention of 97% after 350 circles. The excellent rate performance presents the capacity of 173.6 mAh g(-1) at the current density of 5 A g(-1). Moreover, the large current reversible capacity (20 A g(-1)) can reach 172.2 mAh g(-1) with long-term cycling stability over 500 cycles. Therefore, the superior electrochemical performances are attributed to the stable core-shell mesoporous structure and in-situ nitrogen doped carbon, which is not only improve the electron transport and lithium ion diffusion, but also facilitate the immersion of electrolyte. (C) 2019 Elsevier B.V. All rights reserved.