Preparation method of a nanotube hierarchically structured lithium titanate and use and product thereof

Patent metadata

Field	Value
Publication number	US-2020071184-A1
Application number	US-201916556224-A
Country	US
Kind code	A1
Filing date	Aug 29, 2019
Priority date	Aug 30, 2018
Publication date	Mar 5, 2020
Grant date	—

Abstract

A preparation method of a nanotube hierarchically structured lithium titanate includes the steps of: S1. dispersing a titanium source into an aqueous solution containing lithium hydroxide and hydrogen peroxide and stirring to obtain a mixed solution; S2. subjecting the mixed solution obtained in step S1 to a reaction by heating to obtain a precursor having a nanowire-like structure; S3. subjecting the precursor having a nanowire-like structure obtained in step S2 to separation and drying; S4. subjecting the precursor having a nanowire-like structure after separation and drying to a low-temperature annealing treatment; S5. subjecting the precursor having a nanowire-like structure after the low-temperature annealing treatment to a liquid thermal reaction to obtain the nanotube hierarchically structured lithium titanate. The method includes a simple process and easily controllable process parameters, and may be easily scaled-up for industrial production.

First claim

1 . A preparation method of a nanotube hierarchically structured lithium titanate, wherein the method comprises the steps of:
S1. dispersing a titanium source into an aqueous solution containing lithium hydroxide and hydrogen peroxide and stirring to obtain a mixed solution; S2. subjecting the mixed solution obtained in step S1 to a reaction by heating to obtain a precursor having a nanowire-like structure; S3. subjecting the precursor having a nanowire-like structure obtained in step S2 to separation and drying; S4. subjecting the precursor having a nanowire-like structure after separation and drying to a low-temperature annealing treatment; and S5. subjecting the precursor having a nanowire-like structure after the low-temperature annealing treatment to a liquid thermal reaction to obtain the nanotube hierarchically structured lithium titanate.

2 . The preparation method according to claim 1 , wherein the titanium source is selected from one or more of titanium ethoxide, titanium isopropoxide, titanium propoxide, tetrabutyl titanate, titanium glycolate, titanium glyceroxide, titanium sulfate, titanium oxysulfate, titanium tetrachloride, titanium tetrafluoride, ammonium fluorotitanate, titanium nitride, titanium oxide, metatitanic acid, and orthotitanic acid.

3 . The preparation method according to claim 1 , wherein the titanium source is selected from titanic acid hydrate.

4 . The preparation method according to claim 3 , wherein the titanic acid hydrate is obtained from a hydrolysis reaction of a titanium-containing compound.

5 . The preparation method according to claim 4 , wherein the titanium-containing compound is selected from one or more of titanium ethoxide, titanium isopropoxide, titanium propoxide, tetrabutyl titanate, titanium glycolate, titanium glyceroxide, titanium sulfate, titanium oxysulfate, titanium tetrachloride, titanium tetrafluoride, and ammonium fluorotitanate.

6 . The preparation method according to claim 3 , wherein in the hydrolysis reaction, the titanium-containing compound is dispersed in pure water to be directly hydrolyzed to form the titanic acid hydrate; or
in the hydrolysis reaction, the titanium-containing compound is dispersed in an aqueous solution containing an alkali substance to be hydrolyzed to form the titanic acid hydrate.

7 . The preparation method according to claim 6 , wherein the titanic acid hydrate is obtained by subjecting the titanium-containing compound to a hydrolysis reaction and a purification treatment; and the purification treatment comprises purifying the product obtained after the hydrolysis reaction of the titanium-containing compound to obtain a titanic acid hydrate having a purity of 97% or more.

8 . The preparation method according to claim 1 , wherein, in step S1, the concentration of lithium hydroxide in the aqueous solution containing lithium hydroxide and hydrogen peroxide is 0.4 mol/L to 1.0 mol/L, and the volume fraction of hydrogen peroxide in the aqueous solution containing lithium hydroxide and hydrogen peroxide is 0.5% to 10%.

9 . The preparation method according to claim 1 , wherein the reaction by heating in step S2 is carried out by heating the mixed solution to a temperature of 60° C. to 100° C.

10 . The preparation method according to claim 9 , wherein, the duration of the reaction is 0.5 h to 24 h.

11 . The preparation method according to claim 1 , wherein the drying in step S3 is carried out at a temperature of 20° C. to 80° C.

12 . The preparation method according to claim 1 , wherein the low-temperature annealing treatment in step S4 is carried out at a temperature of 120° C. to 200° C. for a duration of 0.5 h to 12 h.

13 . The preparation method according to claim 1 , wherein the low-temperature annealing treatment in step S4 is a low-temperature annealing treatment carried out in an air atmosphere, an inert gas atmosphere or a reducing gas atmosphere.

14 . The preparation method according to claim 1 , wherein the liquid thermal reaction in step S5 is carried out at a temperature of 80° C. to 150° C. for a duration of 1 h to 24 h.

15 . The preparation method according to claim 1 , wherein the method further comprises the step of surface modification of the nanotube hierarchically structured lithium titanate obtained in step S5, wherein the step of surface modification comprises loading the nanotube hierarchically structured lithium titanate with one or more of carbon, carbon nanotubes, graphene, and black phosphorus.

16 . A nanotube hierarchically structured lithium titanate prepared by the preparation method according to claim 1 .

17 . A preparation method of a nanotube hierarchically structured titanium oxide, wherein the method comprises subjecting the nanotube hierarchically structured lithium titanate according to claim 16 to acid exchange to obtain the nanotube hierarchically structured titanic acid, subjecting the nanotube hierarchically structured titanic acid to a hydrothermal reaction and/or high temperature annealing to obtain the nanotube hierarchically structured titanium oxide.

18 . The preparation method according to claim 17 , wherein, the hydrothermal reaction is carried out at a temperature of 100° C. to 200° C. for a duration of 1 h to 24 h; the high temperature annealing is carried out at a temperature of 350° C. to 800° C. for a duration 1 h to 24 h.

19 . The preparation method according to claim 17 , wherein, the method comprises subjecting the nanotube hierarchically structured lithium titanate to an acid exchange, followed by washing, separation, and drying, to obtain the nanotube hierarchically structured titanic acid, subjecting the nanotube hierarchically structured titanic acid to a hydrothermal reaction and/or high temperature annealing to obtain the nanotube hierarchically structured titanium oxide.

20 . The preparation method according to claim 17 , wherein the acid exchange comprises placing the nanotube hierarchically structured lithium titanate into an acid solution for hydrogen ion exchange to obtain the nanotube hierarchically structured titanic acid.

Assignees

• Petrochina Co Ltd

Inventors

• Jin Xu
• Li Jianming
• Liu He
• Jiao Hang
• Wang Xiaoqi
• Sun Liang
• Liu Xiaodan

Classifications

• C01P2004/13

  Nanotubes · CPC title

• C01P2004/03

  obtained by SEM · CPC title

• C01G23/047

  Titanium dioxide · CPC title

• C01G23/005 Primary

  Alkali titanates · CPC title

• C01D15/00

  Lithium compounds · CPC title