Hierarchically porous nanoflowers from TiO2–B nanosheets with ultrahigh surface area for advanced lithium-ion batteries

• The hierarchically porous TiO2–B nanoflowers are constructed by many ultrathin nanosheets, presenting ultrahigh specific surface area as high as 214.6 m2 g−1.
• The TiO2–B electrode delivers high reversible capacity of 285 mA h g−1 at 1 C, and decreases from 196 to 181 mAh g−1 at 10 C rate during 100 cycles.
• The excellent electrochemical properties of TiO2–B are attributed to the ultrahigh surface area, pseudocapacitive mechanism and scrupulous nanoarchitecture.

In this work, hierarchically porous TiO2–B nanoflowers have been successfully synthesized via a facile solvothermal method followed by calcination treatment. The TiO2–B nanoflowers are constructed by thin nanosheets, presenting ultrahigh specific surface area, up to 214.6 m2 g−1. As anode materials for Li-ion batteries, the TiO2–B sample shows high reversible capacity, excellent cycling performance and superior rate capability. The specific capacity of TiO2–B could remain over 285 mA h g−1 at 1 C and 181 mA h g−1 at 10 C rate after 100 cycles. We believe that the pseudocapacitive mechanism, ultrahigh surface area and scrupulous nanoarchitecture of the TiO2–B are responsible for the enhancement of electrochemical properties.