Facile synthesis of Na0.23TiO2 nanoparticles anode wrapped within full carbon network with high-rate capability for sodium ion battery application

Abstract

In this report, a pure phase of monoclinic Na0.23TiO2 anode was successfully synthesized under carbon network using polyol-assisted pyro synthesis method for sodium ion battery application. The polyol used in the synthesis method acts not only as a solvent, low-cost fuel, reducing agent but also acts as a carbon source, which leads to the formation of carbon network. X-ray diffraction and Raman analysis confirmed the presence of pure phase of monoclinic Na0.23TiO2 and existence of carbon in the synthesized sample, respectively. Morphological analysis clearly displayed that Na0.23TiO2 nanoparticles are fully covered by carbon network. Electrochemical investigations showed that Na0.23TiO2 nanoparticles wrapped within full carbon network exhibits the specific capacity of ∼78 mAh g−1 at 500 mA g−1 and ∼63 mAh g−1 at 2000 mA g−1 up to 500 and 2000 cycles, respectively, indicating the long cycling stability. More importantly, it can be also seen that the specific capacity at various current densities is highly stable with negligible loss, indicating remarkable rate capability of Na0.23TiO2 electrode. To the best of our knowledge, this is the first report for the fabrication of Na0.23TiO2 nanoparticles anode wrapped within full carbon network using cost effective polyol-assisted pyro synthesis method with excellent electrochemical performances.