Preparation , product and application for tubular lithium titanate/titanium dioxide composite material with rule defects

Abstract

The invention discloses a preparation method , product and application for a tubular lithium titanate / titanium dioxide composite material with rule defects. A unique ultraviolet excitation and hydrothermal method can be utilized as a technical path, and the tubular Li4Ti5O12 / TiO2 composite material with rule defects consisting of nanosheets can be synthetized through the hydrolysis conversion andcalcination treatment of titanium glycolate. The composite material consists of Li4Ti5O12 and TiO2 ultrathin nanosheets; and massive defect structures exist between the Li4Ti5O12 and TiO2 crystallite.Through the existence of the rule defects, the material can show extremely excellent electrochemical performance, and especially can be applied to lithium ion battery electrode materials. The preparation method is simple in operation, low in preparation cost and suitable for large scale production.

Description

technical field

[0001] The invention relates to the technical field of lithium-ion battery electrode materials, in particular to a preparation method of a tubular lithium titanate / titanium dioxide composite material with regular defects and its product and application. Background technique

[0002] The study of crystal defects is an active and rapidly developing field in solid-state science. For crystalline materials, the presence of defects can lead to rich chemical structures and unexpected properties. For example, in solid-state reactions, mass transfer can be achieved only when the reactants have a certain concentration of defects. Oxygen-deficient ferrites with a spinel structure can effectively decompose carbon dioxide into carbon through the transfer of oxygen vacancies. The presence of defects in the crystal structure can enhance the mobility of lithium ions and electrons in electrode materials. Therefore, it is expected to greatly improve the rate performance of ...

Examples

Embodiment 1

[0023] A method for preparing a tubular lithium titanate / titanium dioxide composite material containing regular defects, using ultraviolet light excitation and hydrothermal method as a technical path, through the hydrolysis conversion and calcination of titanium ethylene glycol to synthesize nanosheets containing regular defects Defective tubular Li 4 Ti 5 o 12 / TiO 2 Composite materials, follow the steps below:

[0024] a. Porous amorphous TiO 2 Rod preparation: Measure 5 ml of n-tetrabutyl titanate and add dropwise to 200 ml of ethylene glycol, stir at 160 oReflux at C for 2 h to obtain a white precipitate of titanium glycolate. The obtained white titanium ethylene glycol was washed several times with ethanol, dispersed in an aqueous solution, and irradiated with a 150 W mercury lamp for 4 hours under ultraviolet light to obtain porous amorphous TiO 2 Great.

[0025] b.Li 4 Ti 5 o 12 / TiO 2 Tube preparation: Weigh 0.24 g of the porous amorphous TiO obtained in ste...

Embodiment 2

[0028] A method for preparing a tubular lithium titanate / titanium dioxide composite material containing regular defects, similar to Example 1, as follows:

[0029] a. Porous amorphous TiO 2 Rod preparation: Measure 5 ml of n-tetrabutyl titanate and add dropwise to 300 ml of ethylene glycol, stir at 160 o Reflux at C for 2 h to obtain a white precipitate of titanium glycolate. The obtained white titanium ethylene glycol was washed several times with ethanol, dispersed in an aqueous solution, and irradiated with a 300 W mercury lamp for 4 hours under ultraviolet light to obtain porous amorphous TiO 2 Great.

[0030] b.Li 4 Ti 5 o 12 / TiO 2 Tube preparation: Weigh 0.36 g of the porous amorphous TiO obtained in step a 2 rod, dispersed it into 50 ml of deionized water, and added 0.18 g of lithium hydroxide at the same time. After stirring for half an hour, the resulting suspension was transferred to a stainless steel autoclave with a Teflon liner, at 140 o C under hydrother...

Embodiment 3

[0032] A method for preparing a tubular lithium titanate / titanium dioxide composite material containing regular defects, similar to Example 1, as follows:

[0033] a. Porous amorphous TiO 2 Rod preparation: Measure 10 ml of n-tetrabutyl titanate and add dropwise to 400 ml of ethylene glycol, stir at 160 o Reflux at C for 2 h to obtain a white precipitate of titanium glycolate. The obtained white titanium ethylene glycol was washed several times with ethanol, dispersed in an aqueous solution, and irradiated with a 300 W mercury lamp for 4 hours under ultraviolet light to obtain porous amorphous TiO 2 Great.

[0034] b.Li 4 Ti 5 o 12 / TiO 2 Tube preparation: Weigh 0.72 g of the porous amorphous TiO obtained in step a 2 rod, dispersed it into 200 ml of deionized water, while adding 0.14 g of lithium hydroxide, after stirring for half an hour, the resulting suspension was transferred to a stainless steel autoclave with a Teflon liner, at 130 o C under hydrothermal reaction...

technical field

[0001] The invention relates to the technical field of lithium-ion battery electrode materials, in particular to a preparation method of a tubular lithium titanate / titanium dioxide composite material with regular defects and its product and application. Background technique

[0002] The study of crystal defects is an active and rapidly developing field in solid-state science. For crystalline materials, the presence of defects can lead to rich chemical structures and unexpected properties. For example, in solid-state reactions, mass transfer can be achieved only when the reactants have a certain concentration of defects. Oxygen-deficient ferrites with a spinel structure can effectively decompose carbon dioxide into carbon through the transfer of oxygen vacancies. The presence of defects in the crystal structure can enhance the mobility of lithium ions and electrons in electrode materials. Therefore, it is expected to greatly improve the rate performance of ...

Examples

Embodiment 1

[0023] A method for preparing a tubular lithium titanate / titanium dioxide composite material containing regular defects, using ultraviolet light excitation and hydrothermal method as a technical path, through the hydrolysis conversion and calcination of titanium ethylene glycol to synthesize nanosheets containing regular defects Defective tubular Li 4 Ti 5 o 12 / TiO 2 Composite materials, follow the steps below:

[0024] a. Porous amorphous TiO 2 Rod preparation: Measure 5 ml of n-tetrabutyl titanate and add dropwise to 200 ml of ethylene glycol, stir at 160 oReflux at C for 2 h to obtain a white precipitate of titanium glycolate. The obtained white titanium ethylene glycol was washed several times with ethanol, dispersed in an aqueous solution, and irradiated with a 150 W mercury lamp for 4 hours under ultraviolet light to obtain porous amorphous TiO 2 Great.

[0025] b.Li 4 Ti 5 o 12 / TiO 2 Tube preparation: Weigh 0.24 g of the porous amorphous TiO obtained in ste...

Embodiment 2

[0028] A method for preparing a tubular lithium titanate / titanium dioxide composite material containing regular defects, similar to Example 1, as follows:

[0029] a. Porous amorphous TiO 2 Rod preparation: Measure 5 ml of n-tetrabutyl titanate and add dropwise to 300 ml of ethylene glycol, stir at 160 o Reflux at C for 2 h to obtain a white precipitate of titanium glycolate. The obtained white titanium ethylene glycol was washed several times with ethanol, dispersed in an aqueous solution, and irradiated with a 300 W mercury lamp for 4 hours under ultraviolet light to obtain porous amorphous TiO 2 Great.

[0030] b.Li 4 Ti 5 o 12 / TiO 2 Tube preparation: Weigh 0.36 g of the porous amorphous TiO obtained in step a 2 rod, dispersed it into 50 ml of deionized water, and added 0.18 g of lithium hydroxide at the same time. After stirring for half an hour, the resulting suspension was transferred to a stainless steel autoclave with a Teflon liner, at 140 o C under hydrother...

Embodiment 3

[0032] A method for preparing a tubular lithium titanate / titanium dioxide composite material containing regular defects, similar to Example 1, as follows:

[0033] a. Porous amorphous TiO 2 Rod preparation: Measure 10 ml of n-tetrabutyl titanate and add dropwise to 400 ml of ethylene glycol, stir at 160 o Reflux at C for 2 h to obtain a white precipitate of titanium glycolate. The obtained white titanium ethylene glycol was washed several times with ethanol, dispersed in an aqueous solution, and irradiated with a 300 W mercury lamp for 4 hours under ultraviolet light to obtain porous amorphous TiO 2 Great.

[0034] b.Li 4 Ti 5 o 12 / TiO 2 Tube preparation: Weigh 0.72 g of the porous amorphous TiO obtained in step a 2 rod, dispersed it into 200 ml of deionized water, while adding 0.14 g of lithium hydroxide, after stirring for half an hour, the resulting suspension was transferred to a stainless steel autoclave with a Teflon liner, at 130 o C under hydrothermal reaction...

Images