Nanoengineering of N-doped carbon-coated anatase TiO2 nanoparticles for high-performance sodium ion battery

Anatase TiO2 has been widely reported using as anodes of sodium-ion battery (SIB) due to its eco-friendly, electrochemical stability and favorable capacity of sodium ions storage. Herein, a facile and efficient method based on pyrolysis process converting polydopamine-coated industrial metatitanic acid to N-doped carbon-coated anatase TiO2 (TiO2@C) was introduced for sodium ion battery. The electrochemical measurements demonstrated that the TiO2@C sample delivered a reversible capacity of 270 mA h g−1 at a current of 0.1 A g−1 after 100 cycles in ether-based electrolyte. In particular, within ester-based electrolyte, an ultralong cycling life on the sample TiO2@C was obtained, 130 mA h g−1 at 1 A g−1 after 10,000 cycles. Furthermore, the Na-ion full-cell assembled TiO2@C with Na3V2(PO4)3 in ester-based electrolyte demonstrated an energy density as high as ca. 300 W h kg−1.