Sodium Titanate/Carbon (Na2Ti3O7/C) Nanofibers via Electrospinning Technique as the Anode of Sodium-ion Batteries

To overcome the sluggish kinetics in sodium-ion batteries, sodium titanate/carbon (Na2Ti3O7/C) composite nanofibers as anode materials have successfully been synthesized via a simple electrospinning method. After calcination at 800 degrees C for 3h, the obtained Na2Ti3O7 nanoparticles are randomly dispersed in the matrix of in situ pyrolized carbon nanofiber. The Na2Ti3O7/C hybrid nanofiber obtained with 2.5wt% of poly (vinylpyrrolidone) additive in the precursor solution has the smallest diameter of similar to 120nm and the finest particle size of similar to 40nm, exhibiting the best rate performance of 101 mAh center dot g(-1) at 4 C and excellent capacity retention of 82% at 1 C after 100 cycles. Furthermore, this composite nanofiber also demonstrates good cycling performance under low current density of 0.1 C, which is attributed to the formation of stable solid electrolyte interface (SEI) film induced by small volume expansion/contraction of the fine Na2Ti3O7 nanoparticles during the charge/discharge process.