Self-Assembled Synthesis of Mesocrystalline TiO2@C-rGO Hybrid Nanostructures for Highly Reversible Sodium Storage

Abstract

With the aim of enhancing the electrochemical kinetics and capacity of the TiO2 electrode for Na ion batteries (NIBs), we have designed a hybrid material of carbon-coated TiO2 mesocrystals anchored on reduced graphene oxide (TiO2@C-rGO). Such hybrid nanostructures are fabricated through a facile one-step route including in situ growth of oriented self-assembly of TiO2 mesocrystals on GO. TiO2@C-rGO possesses a very large surface area (279 m2 g–1), mesoporous nature, and single-crystal-like structure. It is also found that the capacity of TiO2 electrode for NIBs could be improved by carbon coating at a low current rate, but pure TiO2 shows better rate performance than that of TiO2@C. Remarkably, the enhanced electrochemical kinetics and large capacity can be simultaneously achieved by designing hybrid material. The hybrid nanostructures exhibit a highly reversible capacity of 300 mAh g–1 at 100 mA g–1, superior rate capability, and long-term cycling stability (a stable capacity of 159 mAh g–1 can be mainta...