麻豆淫院

The research team of Prof. Xiaobo Ji and associate Prof. Guoqiang Zou has proposed an ingenious oxygen vacancy (OV) engineering strategy to realize high content anionic doping in TiO₂ and offered valuable insights into devise electrode materials with fast charge transfer kinetics in the bulk phase. The article titled "High content anion (S/Se/P) doping assisted by defect engineering with fast charge transfer kinetics for high-performance sodium ion capacitors" is published in Science Bulletin. Xinglan Deng is listed as first author and Prof. Guoqiang Zou as corresponding author.

The rate-determining process for sodium storage in TiO₂ is greatly dependent on charge transfer happening in the electrode materials owing to its inferior diffusion coefficient and electronic conductivity. Apart from reducing the diffusion distance of ion/electron, the increasement of ionic/electronic mobility in crystal lattice is very important for charge transport. Here, an OV engineering assisted in high content anion (S/Se/P) doping strategy to enhance its charge transfer kinetics for ultrafast sodium-storage performance is proposed. The theoretical calculations have predicted that OV-engineering evokes the spontaneous S doping into TiO₂ phase and achieves high anionic dopant concentration to bring about impurity state electron donor and electronic delocalization over S occupied sites, which can largely reduce the migration barrier of Na+. Accordingly, experimental measurements validate the realization of high content anion (S/Se/P) doping and the significantly enhanced Na ion diffusivity and conductivity in prepared electrode materials.

The optimized A-TiO₂-x-S/C anode (with S content of 9.82 at%) exhibits extraordinarily high-rate capability with 209.6 mAh g^-1 at 5000 mA g^-1. When applied as anode materials, the assembled SIC delivers an ultrahigh energy density of 150.1 Wh kg^-1 at a power density of 150 W kg^-1. This work provides a new strategy to realize the high content doping of anion, and enhance the charge transfer kinetics for TiO₂, which sheds a light on the design of electrode materials with fast kinetic.