CN106179352A - A kind of heterogeneous metatitanic acid Ni-based nano-particle catalysis material and preparation method thereof - Google Patents

Abstract

The invention belongs to the technical field of energy material manufacturing, and in particular relates to a heterogeneous nickel titanate-based nanoparticle photocatalytic material and a preparation method thereof. The preparation method is as follows: uniformly mix the nickel source, ethanol and acid, place it on a constant temperature magnetic stirrer and stir for 30-60 minutes; Cool to room temperature, then add deionized water, and stir evenly; after drying the obtained solution at low temperature, the precursor of nickel titanate is obtained; after calcining the precursor of nickel titanate obtained, the photocatalytic Material. The heterogeneous nickel titanate-based nanoparticle semiconductor photocatalytic material directly synthesized by the one-step method of the present invention has the advantages of stable growth, uniform size, large specific surface area, and many surface active sites, effectively increasing the separation of photogenerated carriers, The rate of electron transmission is increased, the utilization rate of sunlight is improved, and the photocatalytic performance is high.

Description

A kind of heterogeneous nickel titanate-based nanoparticle photocatalytic material and preparation method thereof

technical field

The invention belongs to the technical field of energy material manufacturing, and in particular relates to a heterogeneous nickel titanate-based nanoparticle photocatalytic material and a preparation method thereof.

Background technique

With the discharge of industrial wastewater, it will inevitably enter the water environment, causing water pollution, resulting in long-term deterioration of polluted water quality, and seriously endangering human health. Therefore, research on the degradation of water pollutants is a major problem faced by countries all over the world. Because sunlight is inexhaustible, people are paying more and more attention to the development and utilization of solar energy, and the search for new photocatalysts is a problem that researchers are widely concerned about. The use of semiconductor photocatalytic oxidation technology to degrade water pollutants is a research hotspot in environmental governance in recent years. A large number of studies have proved that many refractory organic substances can be effectively removed or degraded under the action of photocatalytic oxidation.

Nickel titanate material is a kind of IIB-VIA semiconductor compound with a bandgap of 2.8eV at room temperature, good electrical conductivity and a wide range of absorption waves. It is a promising photocatalytic material and is expected to be used in Play an important role in solving the problem of organic dyes and environmental pollution. According to literature reports, single-phase nanotubes and nanorods of nickel titanate have been prepared by hydrothermal method, sol-gel method, flux method, Pechini method, co-precipitation method, etc. However, the prepared single-phase nickel titanate has a high recombination probability of photogenerated carriers, and it is difficult to make full use of sunlight.

Nickel oxide is a P-type antiferromagnetic semiconductor functional material with a bandgap of about 3.6eV. It has been widely used in the fields of gas sensors, catalysts, fuel cell electrodes, optically active fibers, and magnetic materials. favored by those. Liu et al. (Liu L, Li Y, Yuan S M, J. Phys. Chem. C, 2010, 114, 251-255) synthesized nickel oxide nanospheres with hierarchical structure using hexamethylenetetramine as an additive. Wei Fei et al. (Wei F, Wu Y F, Luo LH, [J].Chinese Ceramic Society, 2009, 37(12):1975-1981(in Chinese)) adopt uniform precipitation method, in methanol-water medium with urea and Nickel nitrate was used as the raw material to prepare flower-like NiO nanosheet self-assembly. However, the operation process involved in their experiments was more complicated (such as time-consuming removal of the template) and it was easy to increase the cost of the experiment, resulting in energy consumption of consumables. Therefore, adopting a simple and effective method to realize the construction and control design of the morphology and size structure of NiO inorganic materials is still the key to research.

Contents of the invention

Aiming at the deficiencies in the prior art, the present invention aims to provide a heterogeneous nickel titanate-nickel oxide-titanium dioxide nanoparticle photocatalytic material and a preparation method thereof.

For realizing above-mentioned purpose of the invention, the technical scheme that the present invention adopts is:

A method for preparing a heterogeneous nickel titanate-based nanoparticle photocatalytic material, comprising the steps of:

(1) Mix nickel source, ethanol and acid evenly, place on a constant temperature magnetic stirrer and stir for 30-60 minutes; cool to room temperature, add titanium source to fully react nickel source and titanium source, and cool to room temperature again after the reaction , then add deionized water, and stir evenly; after drying the obtained solution at low temperature, the precursor of nickel titanate is obtained;

(2) Calcining the nickel titanate precursor obtained in step (1) in sections to obtain a heterogeneous nickel titanate-based nanoparticle photocatalytic material.

In the above solution, the molar ratio of the nickel source to the titanium source is 1:1-2.

In the above scheme, the volume ratio of the ethanol, acid and deionized water is 5:1:1˜5:2:2.

In the above scheme, the nickel source is nickel nitrate or nickel acetate.

In the above scheme, the acid is nitric acid or acetic acid.

In the above scheme, the titanium source is isopropyl titanate or n-butyl titanate.

In the above scheme, the drying temperature of the low-temperature drying in step (1) is 40-60° C., and the drying time is 6-20 hours.

In the above scheme, the segmental calcination process described in step (2) is: 200-300°C, 2-3h; 400-500°C, 2-3h, 600-700°C, 4-6h, the heating rate is 2-3h 5°C/min.

The heterogeneous nickel titanate-based nanoparticle photocatalytic material prepared by the above preparation method.

Beneficial effects of the present invention: (1) The present invention adopts the solution-calcination method to prepare heterogeneous nickel titanate-based nanoparticles. Compared with the high-temperature calcination synthesis process in the prior art, the multiphase titanium obtained by the preparation method Nickel-acid-based nanoparticles grow more stably and have a more uniform size; at the same time, they also have the advantages of large specific surface area and many surface active sites, which can effectively increase the separation of photogenerated carriers, increase the rate of electron transport, and improve the efficiency of sunlight. (2) The present invention adopts one-step method to directly synthesize heterogeneous nickel titanate-based nanoparticle semiconductor photocatalytic material, and the preparation method is simple and easy to operate.

Description of drawings

Fig. 1 is the X-ray diffraction pattern of the heterogeneous nickel titanate-based nanoparticles of Examples 1, 2, and 3 of the present invention.

Fig. 2 is a scanning electron microscope (SEM) image of heterogeneous nickel titanate-nickel oxide nanoparticles according to Example 1 of the present invention.

Fig. 3 is a scanning electron microscope image of heterogeneous nickel titanate-nickel oxide-titania nanoparticles according to Example 2 of the present invention.

Fig. 4 is a scanning electron microscope image of heterogeneous nickel titanate-nickel oxide-titania nanoparticles in Example 3 of the present invention.

Fig. 5 is a diagram of the degradation rate of photocatalytic degradation of nitrobenzene by the heterogeneous nickel titanate-based nanoparticles prepared in the embodiment of the present invention.

Fig. 6 is a diagram of the degradation rate of photocatalytic degradation of nitrobenzene by the heterogeneous nickel titanate-based nanoparticles prepared in the embodiment of the present invention.

detailed description

In order to better understand the present invention, the content of the present invention is further illustrated below in conjunction with the examples, but the content of the present invention is not limited to the following examples.

Example 1

A heterogeneous nickel titanate-based nanoparticle photocatalytic material is prepared by the following method:

(1) Dissolve 0.016moL of nickel nitrate in 10mL of ethanol, place it on a constant temperature magnetic stirrer at 25°C, add 2mL of concentrated nitric acid and keep stirring until the nickel nitrate is completely dissolved, continue stirring for 30-60min;

(2) Cool the solution obtained in step (1) to room temperature, and add 0.0128 mol of isopropyl titanate (the molar ratio of titanium source to nickel source is 1.25:1);

(3) After the solution obtained in step (2) is cooled to room temperature, add 2-4 mL of deionized water and stir evenly;

(4) Dry the solution obtained in step (3) in an oven, the temperature is controlled at 60° C., and the drying time is 20 hours to obtain a precursor of nickel titanate;

(5) Put the nickel titanate precursor obtained in step (4) in a muffle furnace for calcination: calcination at 300°C for 2 hours, calcination at 400°C for 2 hours, calcination at 650°C for 4 hours, and a heating rate of 2°C/min. After the calcination, That is, heterogeneous nickel titanate-based nanoparticles are obtained.

The X-ray diffraction pattern (XRD) of the heterogeneous nickel titanate-based nanoparticles prepared in this example is shown in Figure 1, 24.16°, 33.13°, 35.69°, 40.89°, 49.49°, 54.03°, 57.40°, 62.50° , 64.12° correspond to nickel titanate (012), (104), (110), (113), (024), (116), (018), (214),

(300) crystal plane. 37.23° and 43.29° correspond to the (001) and (200) crystal planes of nickel oxide, respectively, indicating that the synthesized heterogeneous nickel titanate-based nanoparticles are heterogeneous nickel titanate-nickel oxide nanoparticles, and the main phase is nickel titanate .

The scanning electron micrograph of the heterogeneous nickel titanate-nickel oxide nanoparticles prepared in this embodiment is shown in Fig. 2, and the size of the heterogeneous nickel titanate-nickel oxide nanoparticles is relatively stable from the scanning diagram, and the size of the nanoparticles is Around 80nm.

Example 2

A heterogeneous nickel titanate-based nanoparticle photocatalytic material is prepared by the following method:

(1) Dissolve 0.016moL of nickel nitrate in 10mL of ethanol, place it on a constant temperature magnetic stirrer at 25°C, add 2mL of concentrated nitric acid and keep stirring until the nickel nitrate is completely dissolved, continue stirring for 30-60min;

(2) Cool the solution obtained in step (1) to room temperature, and add 0.0154 mol of isopropyl titanate (the molar ratio of titanium source to nickel source is 1.04:1);

(3) After the solution obtained in step (2) is cooled to room temperature, add 2-4 mL of deionized water and stir evenly;

(4) Dry the solution obtained in step (3) in an oven, the temperature is controlled at 60° C., and the drying time is 18 hours to obtain the precursor of nickel titanate;

(5) Put the nickel titanate precursor obtained in step (4) in a muffle furnace for calcination: calcination at 300°C for 2 hours, calcination at 400°C for 2 hours, calcination at 650°C for 4 hours, and a heating rate of 2°C/min. After the calcination, That is, heterogeneous nickel titanate-based nanoparticles are obtained.

The X-ray diffraction pattern (XRD) of the heterogeneous nickel titanate-based nanoparticles prepared in this example is shown in Figure 1, 24.16°, 33.13°, 35.69°, 40.89°, 49.49°, 54.03°, 57.40°, 62.50° , 64.12° correspond to nickel titanate (012), (104), (110), (113), (024), (116), (018), (214), (300) crystals of orthorhombic crystal system, respectively 37.23° and 43.29° correspond to the (001) and (200) crystal planes of nickel oxide respectively; 25.34° and 48.10° correspond to the (101) and (200) crystal planes of anatase respectively, indicating the synthesis of heterogeneous titanic acid Nickel-nickel oxide-titania nanoparticles, the main phase is nickel titanate.

The scanning electron microscope picture of the heterogeneous nickel titanate-nickel oxide-titanium dioxide nanoparticles prepared in this example is shown in Figure 3. It can be seen from the scanning diagram that the size of the multiphase nickel titanate-nickel oxide-titanium dioxide nanoparticles is relatively stable. The particle size is around 80nm.

Example 3

A heterogeneous nickel titanate-based nanoparticle photocatalytic material is prepared by the following method:

(1) Dissolve 0.016moL of nickel nitrate in 10mL of ethanol, place it on a constant temperature magnetic stirrer at 25°C, add 2mL of concentrated nitric acid and keep stirring until the nickel nitrate is completely dissolved, continue stirring for 30-60min;

(2) Cool the solution obtained in step (1) to room temperature, and add 0.016 mol of isopropyl titanate (the molar ratio of titanium source to nickel source is 1:1);

(3) After the solution obtained in step (2) is cooled to room temperature, add 2-4 mL of deionized water and stir evenly;

(4) Place the solution obtained in step (3) in an oven to dry, the temperature is controlled at 40° C., and the drying time is 20 hours to obtain a precursor of nickel titanate;

(5) Put the nickel titanate precursor obtained in step (4) in a muffle furnace for calcination: calcination at 300°C for 2 hours, calcination at 400°C for 2 hours, calcination at 650°C for 4 hours, and a heating rate of 2°C/min. After the calcination, That is, nickel titanate-based nanoparticles are obtained.

The X-ray diffraction pattern (XRD) of the heterogeneous nickel titanate-based nanoparticles prepared in this example is shown in Figure 1, 24.16°, 33.13°, 35.69°, 40.89°, 49.49°, 54.03°, 57.40°, 62.50° , 64.12° correspond to nickel titanate (012), (104), (110), (113), (024), (116), (018), (214), (300) crystals of orthorhombic crystal system, respectively 37.23° and 43.29° correspond to the (001) and (200) crystal planes of nickel oxide respectively; 25.34° and 48.10° correspond to the (101) and (200) crystal planes of anatase respectively, indicating the synthesis of heterogeneous titanic acid Nickel-nickel oxide-titania nanoparticles, the main phase is nickel titanate.

The scanning electron microscope picture of the heterogeneous nickel titanate-nickel oxide-titanium dioxide nanoparticles prepared in this example is shown in Figure 4, and the size of the heterogeneous nickel titanate-nickel oxide-titanium dioxide nanoparticles is relatively stable from the scanning picture, and the nanometer The particle size is around 80nm.

Take each 20 mg of the heterogeneous nickel titanate-based nanoparticles prepared in Examples 1 to 3 and place them in 80 mL of nitrobenzene aqueous solution with a concentration of 50 ppm. Stir in a dark room for 1 h to reach adsorption-desorption equilibrium. Under visible light irradiation (light intensity For: visible light part 158mWcm ^-2 ), start the degradation reaction, take a sample every 60min, centrifuge, measure the concentration C of the nitrobenzene solution in each sample, take C/C ₀ as the ordinate, and the reaction time as the abscissa, Draw the degradation rate figure (as shown in Figure 5), and the reaction degradation rate is drawn into the degradation rate figure (as shown in Figure 6), as can be seen from Figure 5 and Figure 6, the present invention prepares heterogeneous nickel titanate-based nano The photocatalytic properties of the particles are higher, and the degradation effect of p-nitrobenzene is better.

Apparently, the above-mentioned embodiments are only examples for clear illustration, rather than limiting the implementation. For those of ordinary skill in the art, other changes or changes in different forms can be made on the basis of the above description. It is not necessary and impossible to exhaustively list all the implementation manners here. However, the obvious changes or modifications thus extended are still within the scope of protection of the present invention.

Claims (9)

1. the preparation method of a heterogeneous metatitanic acid Ni-based nano-particle catalysis material, it is characterised in that comprise the steps:

(1) by nickel source, ethanol and acid mix homogeneously, stirring 30 ~ 60min it is placed in constant temperature blender with magnetic force；It is cooled to room temperature, adds Entering titanium source, make nickel source and titanium source fully react, after reaction terminates, be again cooled to room temperature, be subsequently adding deionized water, stirring is all Even；After gained solution cold drying, obtain the presoma of nickel titanate；

(2) by after the presoma calcine by steps of step (1) gained nickel titanate, heterogeneous metatitanic acid Ni-based nano-particle photocatalysis material is obtained Material.

Preparation method the most according to claim 1, it is characterised in that the mol ratio in described nickel source and titanium source is 1:1 ~ 2.

Preparation method the most according to claim 1, it is characterised in that the volume ratio of described ethanol, acid and deionized water is 5:1:1~5:2:2。

Preparation method the most according to claim 1, it is characterised in that described nickel source is nickel nitrate or nickel acetate.

Preparation method the most according to claim 1, it is characterised in that described titanium source is isopropyl titanate or the positive fourth of metatitanic acid Ester.

Preparation method the most according to claim 1, it is characterised in that described acid is nitric acid or acetic acid.

Preparation method the most according to claim 1, it is characterised in that the baking temperature of cold drying described in step (1) Being 40 ~ 60 DEG C, drying time is 6 ~ 20h.

Preparation method the most according to claim 1, it is characterised in that described in step (2), the technique of calcine by steps is: 200 ~ 300 DEG C, 2 ~ 3h；400 ~ 500 DEG C, 2 ~ 3h, 600 ~ 700 DEG C, 4 ~ 6h, heating rate is 2 ~ 5 DEG C/min.

9. the heterogeneous metatitanic acid Ni-based nano-particle catalysis material that the arbitrary described preparation method of claim 1 ~ 8 prepares.