Inorganic material structures with excellent properties have aroused widespread research interest in fast and long-life energy storage devices. Nanostructured titanium dioxide (TiO2), as one of the typical oxides, has become a research hotspot of anode materials for sodium ion batteries (SIB) due to its stable structure, safe use and low cost. One-dimensional (1D) TiO2 nanotubes have attracted great attention from researchers due to their large surface area, fast electron / ion transport, and short ion diffusion paths. In order to make full use of the advantages of 1D TiO2 nanotubes in ultra-fast charging sodium ion batteries, a novel structure and a simple preparation method need to be designed.
Recently, the team of Professor Naiqin Zhao from Tianjin University and Professor Qiao Shiqiao from the University of Adelaide in Australia developed a simple gel derivatization method. For the first time, a 1D slender, non-closed nanotube structure was synthesized, which has a high aspect ratio and an open tubular shape. Anatase / bronze TiO2 nano crystal wall composition, has excellent electron / ion transport and reaction kinetic properties. As a negative electrode material of SIB, this structure exhibits excellent rate and long-cycle performance: after 4,000 cycles at a current density of 16 C, it still has a capacity of 107 mAh g-1, and a capacity of 94 mAh g-1 at 32 C. The characteristics exhibited by this novel nanostructure will have good application potential in ultra-fast and long-life rechargeable batteries. The results were recently published in the top international journal Advanced Materials (IF: 21.950).
The core content of this achievement is: first, the sol-gel method was used to design and synthesize a 1D slender nanoribbon structure with a width of 80 nm, a thickness of 13 nm, and a length of several tens of microns (Fig. In a simple calcination process, the 1D slender nanoribbon structure formed a non-closed nanotube (SNT) at 400 ° C (Figure 1d), with a length of tens of microns, a diameter of 25 nm, and a thickness of 7.8 nm (Figure 2a- c). Further characterization revealed that: TiO2 SNT is composed of fine anatase / bronze TiO2 nanocrystal walls (Figure 2d). The nanometer material's structural morphology and material composition characteristics give it special properties: high aspect ratio and open internal tubular 1D nanostructures ensure high specific surface area and electron / ion transmission properties; anatase / bronze Ore TiO2 nanocrystal walls further enhance the electron / ion diffusion and sodium ion storage sites. Therefore, when TiO2 SNT is used in the negative electrode of sodium ion battery, excellent magnification and long cycle performance are obtained.