Supercapacitor-like Na-ion batteries have attracted much attention due to the high energy density of batteries and power density of capacitors.Titanium dioxide(TiO_(2)),is a promising anode material.Its performance is...Supercapacitor-like Na-ion batteries have attracted much attention due to the high energy density of batteries and power density of capacitors.Titanium dioxide(TiO_(2)),is a promising anode material.Its performance is however seriously hindered by its low electrical conductivity and the sluggish diffusion of sodium ions(Na^(+))in the TiO_(2)matrix.Herein,this work combines porous TiO_(2)nanocubes with carbon nanotubes(CNTs)to enhance the electrical conductivity and accelerate Na^(+)diffusivity for Na-ion batteries(NIBs).In this composite,an interwoven scaffolded TiO_(2)/CNTs framework is formed to provide abundant channels and shorter diffusion pathways for electrons and ions.The in-situ X-ray diffraction and cyclic voltammetry confirm the low strain and superior transport kinetics in Na^(+)intercalation/extraction processes.In addition,the chemically bonded TiO_(2)/CNTs hybrid provides a more feasible channel for Na^(+)insertion/extraction with a much lower energy barrier.Consequently,the TiO_(2)/CNTs composite exhibits excellent electrochemical performance with a capacity of 223.4 m Ah g^(-1)at 1 C and a capacity of 142.8 m Ah g^(-1)at 10 C(3.35 A g^(-1)).The work here reveals that the combination of active materials with CNTs can largely improve the utilization efficiency and enhance their sodium storage.展开更多
基金supported by the National Key R&D Program of China(2016YFA0202602,2016YFA0202603)the National Natural Science Foundation of China(U1663225)+1 种基金the 111 national project(Grant No.B20002)from Ministry of Science and Technologythe Ministry of Education and Sinopec Ministry of Science and Technology Basic Prospective Research Project(218025-9)。
文摘Supercapacitor-like Na-ion batteries have attracted much attention due to the high energy density of batteries and power density of capacitors.Titanium dioxide(TiO_(2)),is a promising anode material.Its performance is however seriously hindered by its low electrical conductivity and the sluggish diffusion of sodium ions(Na^(+))in the TiO_(2)matrix.Herein,this work combines porous TiO_(2)nanocubes with carbon nanotubes(CNTs)to enhance the electrical conductivity and accelerate Na^(+)diffusivity for Na-ion batteries(NIBs).In this composite,an interwoven scaffolded TiO_(2)/CNTs framework is formed to provide abundant channels and shorter diffusion pathways for electrons and ions.The in-situ X-ray diffraction and cyclic voltammetry confirm the low strain and superior transport kinetics in Na^(+)intercalation/extraction processes.In addition,the chemically bonded TiO_(2)/CNTs hybrid provides a more feasible channel for Na^(+)insertion/extraction with a much lower energy barrier.Consequently,the TiO_(2)/CNTs composite exhibits excellent electrochemical performance with a capacity of 223.4 m Ah g^(-1)at 1 C and a capacity of 142.8 m Ah g^(-1)at 10 C(3.35 A g^(-1)).The work here reveals that the combination of active materials with CNTs can largely improve the utilization efficiency and enhance their sodium storage.
