Na+ intercalation pseudocapacitance in graphene-coupled titanium oxide enabling ultra-fast sodium storage and long-term cycling

Sodium-ion batteries are emerging as a highly promising technology for large-scale energy storage applications. However, it remains a significant challenge to develop an anode with superior long-term cycling stability and high-rate capability. Here we demonstrate that the Na+ intercalation pseudocapacitance in TiO2/graphene nanocomposites enables high-rate capability and long cycle life in a sodium-ion battery. This hybrid electrode exhibits a specific capacity of above 90 mA h g−1 at 12,000 mA g−1 (∼36 C). The capacity is highly reversible for more than 4,000 cycles, the longest demonstrated cyclability to date. First-principle calculations demonstrate that the intimate integration of graphene with TiO2…

• NN
  National Natural Science Foundation of China

  Awards: 51472098, 21271078
• PF
  Program for New Century Excellent Talents in University

  Award: NECT-12-0223
• PF
  Program for Changjiang Scholars and Innovative Research Team in University

  Award: IRT1014