摘要
Spinel-type lithium and titanium composite oxide Li4TisO12 was successfully synthesized via a novel hydrolysis method followed by calcination using titanium tetrachloride （TIC14） and lithium hydroxide （LiOH.H2O） as raw materials. Three major factors, including LiOH con- centration, LiOH dosage, and hydrolysis temperature were studied for optimizing the synthetic conditions to obtain a phase-pure Li4Ti5012. The physical and electrochemical properties of samples were characterized by X-ray dif- fraction （XRD）, thermogravimetric analysis （TGA）, fourier transform infrared spectroscopy （FT-IR）, scanning electron microscopy （SEM）, and constant current discharge-charge test. The FT-IR results indicate the presence of [TiO6] octahedra. The SEM images show that the Li4Ti5O12 pre- cursor obtained is an amorphous solid with an irregular and rough morphology. It is revealed that the phase-pure spinel Li4Ti5O12 powders with well crystallization and regular morphology can be obtained by calcining the precursor at 800 ℃ for 6 h. The constant current discharge-charge tests indicate that the Li4TisO12 material delivers an excellent cycling ability, maintaining 93.8 % of its initial specific capacity after 60 cycles at a current density of 0.5C.
Spinel-type lithium and titanium composite oxide Li4TisO12 was successfully synthesized via a novel hydrolysis method followed by calcination using titanium tetrachloride （TIC14） and lithium hydroxide （LiOH.H2O） as raw materials. Three major factors, including LiOH con- centration, LiOH dosage, and hydrolysis temperature were studied for optimizing the synthetic conditions to obtain a phase-pure Li4Ti5012. The physical and electrochemical properties of samples were characterized by X-ray dif- fraction （XRD）, thermogravimetric analysis （TGA）, fourier transform infrared spectroscopy （FT-IR）, scanning electron microscopy （SEM）, and constant current discharge-charge test. The FT-IR results indicate the presence of [TiO6] octahedra. The SEM images show that the Li4Ti5O12 pre- cursor obtained is an amorphous solid with an irregular and rough morphology. It is revealed that the phase-pure spinel Li4Ti5O12 powders with well crystallization and regular morphology can be obtained by calcining the precursor at 800 ℃ for 6 h. The constant current discharge-charge tests indicate that the Li4TisO12 material delivers an excellent cycling ability, maintaining 93.8 % of its initial specific capacity after 60 cycles at a current density of 0.5C.
基金
financially supported by the National Natural Science Foundation of China(No.50774103)
