Li4Ti5O12-TiO2 nanowire arrays constructed with stacked nanocrystals for high-rate lithium and sodium ion batteries

This work reports on nanoparticle-stacked Li4Ti5O12-TiO2 nanowire arrays (SLTO) as anode for lithium and sodium ion battery (NIB). Our finding shows that the pseudocapacitive effect partly contributes to the performance for the NIBs based on the SLTO electrode due to a large size volume of Na+ ions. More importantly, the SLTO nanowires constituting of the nanoparticies efficiently shorten ion diffusion length, thereafter accelerate ion insertion/extraction reaction and improve the rate capability. For the SLTO electrode, a specific capacity of 199.7 mAh g(-1) can be achieved in the LIBs at a current rate of 0.75 C (voltage range of 1.0-3.0 V) and a specific capacity of 94.2 mAh g(-1) is obtained in the NIBs at a high current rate of 15 C (voltage range of 0.5-2.5 V). Most importantly, the sodium ion full battery based on SLTO as anode and Na3V2(PO4)(3) as cathode materials shows stable cycling performance with tiny capacity degradation (90.1 mAh g(-1)) after 200 cycles at a current rate of 4 C (voltage range of 1.0-4.0 V), simultaneously possessing a high energy density of 136.5 Wh kg(-1) at the power density of 312 W kg(-1) (C) 2017 Elsevier B.V. All rights reserved.