Experimental preparation of flaky nickel titanate nanocrystals
The water-based synthesis method addresses the challenge of preparing crystalline NiTiO3 nano materials by dissolving nickel nitrate and titanium isopropoxide, adjusting pH, and heat-treating them, resulting in materials with enhanced gas-sensing properties.
Patent Information
- Application Number
- CN202311246553.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-09-26
- Publication Date
- 2025-03-28
AI Technical Summary
There is a lack of effective methods for preparing crystalline NiTiO3 nano materials, which are essential for expanding the application of Ti-based ABO3 type materials in gas-sensitive semiconductor materials.
A water-based synthesis method involving the sequential dissolution of nickel nitrate and titanium isopropoxide, followed by pH adjustment with sodium hydroxide and subsequent heat treatment at 200°C for 20-28 hours to produce crystalline NiTiO3 nano materials.
This method enables the controlled synthesis of crystalline NiTiO3 nano materials with improved structural and chemical properties, enhancing their gas-sensing capabilities.
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Abstract
Description
Technical Field
[0001] The invention relates to the technical field of metal oxide materials, and in particular to an experimental method for preparing crystalline metal oxide nanomaterials by a hydrothermal method, and applying the method to the field of gas-sensitive semiconductor materials to expand the application range of titanium-based ABO3 type materials. Background Art
[0002] NiTiO3 is an important transition metal oxide with a wide range of potential uses. It exhibits excellent performance in electrocatalysis, photocatalysis, batteries, sensors and ferromagnetism. In recent years, the hydrothermal synthesis of nickel titanate has attracted increasing attention in the field of material synthesis. The hydrothermal method is a low-temperature, high-pressure synthesis method that generates metal oxides with regular crystal structures by reacting metal ions with oxygen sources under hydrothermal conditions. Compared with the traditional solid-phase synthesis method, the hydrothermal method has the following advantages: First, the mild reaction conditions can be carried out at relatively low temperatures and pressures, which is conducive to controlling the crystal size and morphology; second, water as a reaction medium has good solubility and mass transfer properties, which is conducive to the uniform dispersion of reactants and the reaction; third, the hydrothermal method can also adjust the reaction parameters such as temperature, pressure, reaction time and reactant ratio to achieve the regulation of the physical and chemical properties of the synthetic product, thereby further optimizing the performance of nickel titanate. NiTiO3 is an n-type semiconductor that has shown a series of excellent gas-sensitive properties in the field of gas sensors. At present, nanomaterials prepared from polymers, semiconductor metal oxides, graphene and organic / inorganic compounds have been widely used in gas sensors, and the preparation of nanomaterials mainly includes gas phase method, liquid phase method, template method, hydrothermal method and electrospinning method.
[0003] There are few reports on the preparation of crystalline NiTiO3 nanomaterials, and the preparation of crystalline NiTiO3 is still a relatively new topic in the materials field. Summary of the invention
[0004] The purpose of the invention is to provide a method for preparing NiTiO3 crystalline nanomaterials.
[0005] To achieve the above object, the technical solution adopted by the present invention is as follows.
[0006] Step 1: Dissolve analytical grade nickel nitrate in distilled water with constant stirring to prepare Ni 2+ The concentration of the green transparent solution is 0.5mol / L-1mol / L, and the resulting solution is marked as A.
[0007] Step 2: Dissolve analytically pure tetrabutyl titanate in distilled water with constant stirring to prepare Ti 4+ The concentration of the solution is 0.5mol / L – 1mol / L, and the resulting solution is marked as B.
[0008] Step 3: Add solution B to solution A and continue stirring for 30 minutes, marked as C.
[0009] Step 4: After stirring, add sodium hydroxide solution to solution C, adjust the pH value of the solution to 13, and continue stirring for 4-6 hours.
[0010] Step 5: Move the solution to a hydrothermal reactor and place it at 200°C for 20-28 hours. Then filter it with nano filter paper, rinse it with ethanol and distilled water, centrifuge it 4 times, and dry it in a forced air drying oven at 70°C for 5 hours to obtain nickel titanate crystalline nanomaterials. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Figure 1 This is the X-ray powder diffraction pattern (XRD) of the NiTiO3 nanocrystals of Example 1 prepared in the present invention.
[0012] Figure 2 This is a field emission high magnification scanning electron microscope (SEM) of the NiTiO3 nanocrystal of Example 1 prepared in the present invention. DETAILED DESCRIPTION
[0013] The present invention will be further described in detail below in conjunction with the accompanying drawings.
[0014] Example 1: Analytical pure nickel nitrate was dissolved in distilled water with constant stirring to prepare Ni 2+ A green transparent solution with a concentration of 0.5 mol / L was prepared. The obtained solution was labeled A. Analytical pure tetrabutyl titanate was dissolved in distilled water with constant stirring to prepare Ti 4+ The concentration of the light yellow transparent solution is 0.5 mol / L, and the obtained solution is marked as B. Add solution B to solution A and continue stirring for 30 minutes, marked as C. After stirring, add 1.2 mol / L sodium hydroxide solution to solution C, adjust the pH value of the solution to 13, and continue stirring for 4 hours. Move the solution to a hydrothermal reactor and place it at 200°C for 20 hours. Then filter it with nano filter paper, rinse it with ethanol and distilled water, centrifuge it 4 times, and dry it in a forced air drying oven at 70°C for 5 hours to obtain nickel titanate crystalline nanomaterials.
[0015] Example 2: Analytical pure nickel nitrate was dissolved in distilled water with constant stirring to prepare Ni 2+ A green transparent solution with a concentration of 0.5 mol / L was prepared. The obtained solution was labeled A. Analytical pure tetrabutyl titanate was dissolved in distilled water with constant stirring to prepare Ti 4+The concentration of the light yellow transparent solution is 0.5 mol / L, and the obtained solution is marked as B. Add solution B to solution A and continue stirring for 30 minutes, marked as C. After stirring, add 1.2 mol / L sodium hydroxide solution to solution C, adjust the pH value of the solution to 13, and continue stirring for 6 hours. Move the solution to a hydrothermal reactor and place it at 200°C for 20 hours. Then filter it with nano filter paper, rinse it with ethanol and distilled water, centrifuge it 4 times, and dry it in a forced air drying oven at 70°C for 5 hours to obtain nickel titanate crystalline nanomaterials.
[0016] Example 3: Analytical pure nickel nitrate was dissolved in distilled water with constant stirring to prepare Ni 2+ A green transparent solution with a concentration of 0.5 mol / L was prepared. The obtained solution was labeled A. Analytical pure tetrabutyl titanate was dissolved in distilled water with constant stirring to prepare Ti 4+ The concentration of the light yellow transparent solution is 0.5 mol / L, and the obtained solution is marked as B. Add solution B to solution A and continue stirring for 30 minutes, marked as C. After stirring, add 1.2 mol / L sodium hydroxide solution to solution C, adjust the pH value of the solution to 13, and continue stirring for 4 hours. Move the solution to a hydrothermal reactor and place it at 200°C for 28 hours. Then filter it with nano filter paper, rinse it with ethanol and distilled water, centrifuge it 4 times, and dry it in a forced air drying oven at 70°C for 5 hours to obtain nickel titanate crystalline nanomaterials.
[0017] Example 4: Analytical pure nickel nitrate was dissolved in distilled water with constant stirring to prepare Ni 2+ A green transparent solution with a concentration of 0.5 mol / L was prepared. The obtained solution was labeled A. Analytical pure tetrabutyl titanate was dissolved in distilled water with constant stirring to prepare Ti 4+ The concentration of the light yellow transparent solution is 0.5 mol / L, and the obtained solution is marked as B. Add solution B to solution A and continue stirring for 30 minutes, marked as C. After stirring, add 1.2 mol / L sodium hydroxide solution to solution C, adjust the pH value of the solution to 13, and continue stirring for 6 hours. Move the solution to a hydrothermal reactor and place it at 200°C for 28 hours. Then filter it with nano filter paper, rinse it with ethanol and distilled water, centrifuge it 4 times, and dry it in a forced air drying oven at 70°C for 5 hours to obtain nickel titanate crystalline nanomaterials.
Claims
1. An experimental method for preparing flaky nickel titanate by a hydrothermal method, characterized in that: It is composed of metal oxide and mixed composite metal oxide nanocomposite materials.
2. According to claim 1, it is characterized in that: The metal nitrate precursors were dissolved in distilled water by magnetic stirring for 30 min.
3. According to claim 1, it is characterized in that: Tetrabutyl orthotitanate was added to the mixed solution to form a 1 mol / L transparent solution, and the solution was stirred for 30 minutes.
4. According to claim 1, it is characterized in that: 1.2 mol / L sodium hydroxide solution was added and the pH value was adjusted to 13, stirred for 4 h, and then transferred to a hydrothermal reactor vessel at 200° C. for 20 h.
5. Use of the crystalline nickel titanate according to claim 1 as a gas-sensitive semiconductor material.