CN103864139A

CN103864139A - Preparation method of three-dimensional layered multilevel flower-shaped stannic oxide microsphere

Info

Publication number: CN103864139A
Application number: CN201410054728.2A
Authority: CN
Inventors: 陈志文; 王利军; 汪文峰; 焦正; 吴明红
Original assignee: University of Shanghai for Science and Technology
Current assignee: University of Shanghai for Science and Technology
Priority date: 2014-02-18
Filing date: 2014-02-18
Publication date: 2014-06-18

Abstract

The invention discloses a preparation method of a three-dimensional layered multilevel flower-shaped stannic oxide microsphere, belonging to the field of material preparation processes. The preparation method comprises the steps: adding tin dichloride dihydrate powder in a mixed solution of alcohol and water (volume ratio of 1:1), through controlling a concentration and a temperature of tin ions and an amount of urea, and preparing stannic oxide materials of different morphologies, with a three-dimensional multilevel layered structure, under a hydrothermal condition. Researches on the prepared materials prove that the urea is an important influence factor of controlling the three-dimensional multilevel layered structure of stannic oxide, and an oxidation function is a key factor of forming a nanometer sheet. According to the preparation method, the reaction cost can be reduced, the production efficiency of the stannic oxide nano material is increased; and the prepared nano material is controllable in morphology, and has the advantages of high purity, high performance, large specific surface area, and the like, and can be widely applied to new energy devices such as a lithium ion battery, a solar energy battery, a supercapacitor, and can also be applicable to the fields of a catalyst carrier and an information material. Any surfactant or template is needed for assistance, no toxic and harmful organic solvent is used, and used raw materials are low in price and easy to obtain, thus the preparation method is an environment-friendly preparation method.

Description

The preparation method of three-dimensional layered multi-stage flower-like tin dioxide microballoon

Technical field

The preparation method who the invention discloses a kind of three-dimensional layered multi-stage flower-like tin dioxide microballoon, belongs to material preparation process field.

Background technology

Tindioxide is a kind of typical directly broad-band gap n-N-type semiconductorN functional materials, its body band gap is about 3.6eV(in the time of 300K), exciton bind energy is 130meV, and exciton Bohr radius is about 27nm, is the important application material of the aspects such as short-wave long light-emitting device, laser apparatus, solid-state plane demonstration, optical storage, gas sensor.Because this semiconductor material has transition probability greatly and physics or the chemical property advantage such as larger electronic mobility, it is the semiconductor material with widespread use at numerous areas such as the photothermal converters of microelectronics industry, opto-electronic device and solar cell.But microtexture, size of particles and the dimension of tindioxide have a great impact its physics or chemical property, as: three-dimensional layered structure not only has original characteristic, has more some new physics-chem characteristics, therefore, and to SnO ₂the research of Syntheses and more optimal Structure and form has had great interest, and particularly, three-dimensional layered structure has caused sizable concern.

Research preparation SnO ₂method a lot, such as tin oxidation style, carbothermic method, chemical Vapor deposition process, pyrolysis gunite, radio frequency sputtering method, sol-gel method and hydrothermal method etc., particularly hydrothermal method has become the important synthetic method of current field of nanometer material technology.The advantage of chemical gaseous phase deposition method is: the convenient control of technological process, synthetic particle size are evenly distributed, and size can accurately be controlled, better dispersed without bonding.Radio frequency sputtering method sputtering rate is faster, and the output of particulate is higher, and this method is reproducible and controllability is high.Shortcoming is that particle growth speed is slow, and conventional efficient is low, and instrument costliness, and experimental cost is high.Adopt sol-gel method to prepare nano SnO ₂particulate has the following advantages: uniformity coefficient is high, can reach molecule or atomic scale; Purity is high, and this is high owing to preparing material therefor purity, and solvent is easy to remove in preparation process; Firing temperature is low, and reaction process is easy to control, and weak point is: adopt the method treatment time longer, goods easily produce cracking, burn till perfect not etc.

Hydro-thermal reaction is relatively being carried out under high-temperature and pressure condition, can realize the chemical reaction that can not carry out or improve its reaction efficiency under normal condition.It is simple that hydrothermal method has technology and equipment, is easy to control, and without high temperature sintering processing, the advantages such as crystallization and favorable dispersity, conventionally with SnCl ₄5H ₂o or SnCl ₂2H ₂o is the synthetic various nanocrystalline materials of raw material, and this nanocrystalline material synthesizing by hydrothermal method has very good physical and chemical performance.Facts have proved: SnO ₂no matter all there is extremely low solubleness, SnCl under the hydrothermal conditions such as alkalescence, neutrality or strongly-acid ₄under high-temperature water heat condition very easily in hypersaturated state and rapid reaction forms different-grain diameter and the minimum nano SnO of particle ₂crystal, so hydrothermal method is widely used in the preparation of nano material.But because reaction is to carry out under high-temperature and high-pressure conditions, larger to the dependency of equipment, the boiling point of simultaneous reactions medium-water is low, has also limited the development of hydrothermal method.

Summary of the invention

For the defect of prior art existence, the object of this invention is to provide a kind of preparation method of three-dimensional layered multi-stage flower-like tin dioxide microballoon.

For achieving the above object, the present invention adopts following technical scheme:

A preparation method for three-dimensional layered multi-stage flower-like tin dioxide microballoon, has following steps:

1) 0.8 ~ 1.0g urea is dissolved in the deionized water and ethanolic soln that volume ratio is 7:3 to preparation mixing solutions, the SnCl that is 98% by massfraction ₂2H ₂o, as presoma, prepares respectively Sn in mixing solutions ²⁺the suspension liquid of

concentration

10,15 and 20 mM/L, then limit microwave-assisted light shaking mixing solutions, limit drips NaOH solution 0.8 ~ 1.0L of 6M/ml;

2) in the polytetrafluoro pressure kettle of mixing solutions being transferred to, under 150 ~ 160 DEG C of hydrothermal conditions, react 18 ~ 20 hours respectively, products therefrom deionized water wash 3 times, obtain Primary product;

3) Primary product is dispersed in deionized water again, leaves standstill after 30 minutes, remove gray precipitate thing, recentrifuge processing; Vacuum-drying 8 ~ 10 hours under 60 ~ 80 DEG C of conditions, makes three-dimensional layered multi-stage flower-like tin dioxide microballoon.

Compared with prior art, the present invention has following outstanding substantive distinguishing features and significant advantage:

The present invention utilizes the three-dimensional layered multi-stage flower-like tin dioxide of microwave-assisted technology Hydrothermal Synthesis micro-sphere structure, various parameters and the temperature condition of testing by control, under the condition without masterplate, realize the preparation of three-dimensional layered multi-stage flower-like tin dioxide microballoon, there is potential using value in three-dimensional structure field of material preparation.

Brief description of the drawings

Fig. 1 be the present invention X-ray diffractometer figure (a) of preparing the three-dimensional layered multi-stage flower-like tin dioxide microballoon of gained sample 1,

Scanning electron microscope diagram (b), transmission electron microscope figure (c), high power transmission electron microscope figure (d, e, f).

Fig. 2 is the scanning electron microscope diagram that the present invention prepares the three-dimensional layered multi-stage flower-like tin dioxide microballoon of gained sample 2 ~ 6.

Fig. 3 is the X-ray diffractometer figure that the present invention prepares the three-dimensional layered multi-stage flower-like tin dioxide microballoon of gained sample 2 ~ 6.

Fig. 4 is the transmission electron microscope figure that the present invention prepares the three-dimensional layered multi-stage flower-like tin dioxide microballoon of gained sample 2 ~ 6.

Fig. 5 is the high power transmission electron microscope figure that the present invention prepares the three-dimensional layered multi-stage flower-like tin dioxide microballoon of gained sample 2 ~ 6.

Fig. 6 is that the present invention prepares 5 ageings of gained sample and after 30 minutes, its grey matter carried out to X-ray diffractometer figure (a), large volume reactor and pre-oxidation treatment and prepare the scanning electron microscope diagram of the three-dimensional layered multi-stage flower-like tin dioxide microballoon of gained (b, c) and the scanning electron microscope diagram of oxidation after 6,9 and 15 hours (d, e, f).

Fig. 7 is that the present invention prepares the X-ray diffractometer figure that is oxidized respectively gained sample after 6 and 9 hours in sample 8 processes.

Embodiment

Now by as follows specific embodiments of the invention accompanying drawings.

embodiment 1

1) 0.2g urea is dissolved in the mixing solutions of 35ml deionized water and 15ml ethanol, and then adding massfraction is 98%SnCl ₂2H ₂o reaches Sn ²⁺concentration 10 mM/L, vibration forms suspension liquid gently, under microwave-assisted condition, drips NaOH solution 1.0 ml of 6 M/L.

2) solution is transferred in the polytetrafluoro autoclave of 60 ml to constant temperature 18 hours in the baking oven of 160 DEG C.Products therefrom deionized water wash 3 times, obtain Primary product.

3) Primary product is dispersed in deionized water again, leaves standstill after 30 minutes, remove gray precipitate thing, recentrifuge processing.Dry more than 8 hours in 60 DEG C of vacuum drying ovens, obtain three-dimensional layered multi-stage flower-like tin dioxide microballoon sample 1.

embodiment 2

The present embodiment is substantially the same manner as Example 1, and difference is, step 2) in temperature of reaction be 150 DEG C, obtain three-dimensional layered multi-stage flower-like tin dioxide microballoon sample 2.

embodiment 3

The present embodiment is substantially the same manner as Example 1, and difference is, the Sn in step 1) ²⁺concentration reaches 15 mM, obtains three-dimensional layered multi-stage flower-like tin dioxide microballoon sample 3.

embodiment 4

The present embodiment is substantially the same manner as Example 1, and difference is, the Sn in step 1) ²⁺concentration reaches 20 mM, obtains three-dimensional layered multi-stage flower-like tin dioxide microballoon sample 4.

embodiment 5

The present embodiment is substantially the same manner as Example 1, and difference is, the Sn in step 1) ²⁺concentration reaches 20 mM, and drips the NaOH of 0.8 ml, obtains three-dimensional layered multi-stage flower-like tin dioxide microballoon sample 5.

embodiment 6

The present embodiment is substantially the same manner as Example 1, and difference is, the Sn in step 1) ²⁺concentration reaches 20 mM, does not add urea, obtains three-dimensional layered multi-stage flower-like tin dioxide microballoon sample 6.

embodiment 7

The present embodiment is substantially the same manner as Example 1, and difference is, step 2) in the polytetrafluoro autoclave of large volume 100 ml of use, obtain three-dimensional layered multi-stage flower-like tin dioxide microballoon sample 7.

embodiment 8

The present embodiment is substantially the same manner as Example 1, and difference is, before hydro-thermal reaction, in step 1), adds solution after sodium hydroxide to be placed in air 24 hours to Sn ²⁺carry out preoxidation, obtain three-dimensional layered multi-stage flower-like tin dioxide microballoon sample 8.

sample detection and sign

The result of now products therefrom being carried out to instrument detection or sign is described below:

detect test example one:

As shown in Figure 1, the sample obtaining in embodiment 11 is carried out to X-ray diffractometer (XRD), scanning electronic microscope, transmission electron microscope observation, from XRD figure spectrum, (Fig. 1 a) can show that sample is the Tetragonal SnO of highly crystalline ₂scanning electronic microscope (Fig. 1 b), transmission electron microscope (Fig. 1 c) and high power transmission electron microscope (Fig. 1 d, e) tentatively infer that tindioxide is spherical microlitic structure, the multilevel hierarchy structure at spherical surface with nano-sheet (is shown in Fig. 1 c, f), illustrates and successfully make the three-dimensional layered multi-stage structure of tindioxide.

detect test example two:

As shown in Figure 2, the sample obtaining in embodiment 2 ~ 6 is carried out to flying-spot microscope observation, relatively find: five kinds of samples all have ball-type microlitic structure, all form the layered multi-stage structure of nano-sheet at microsphere surface, ((Fig. 2 is more floweriness shape of pattern e) for Fig. 2 c) He 6 for sample 4, (Fig. 2 is b) like the shape of starfish, and (Fig. 2 is d) like the colored shape of rose in full bloom for sample 5 for sample 3.(Fig. 2 a) temperature is 150 DEG C to sample 2, other sample is to prepare under 160 DEG C of conditions, and in sample 2, nanometer sheet branch is not that observing clearly (seen Fig. 2 a), but ball surface irregularity, all the other several sample nano-sheet branches are high-visible, and length is greatly about 200nm.In sample 2-5, nanometer sheet is all pointed to centre of sphere direction, very orderly, in sample 6, the arrangement of nanometer sheet be rambling (see Fig. 2 e), appearance is more similar to penniform, from the first five plant sample different: in sample 6, do not add urea.Illustrate that urea may be to control the important factor in order that the flower-shaped hierarchical multi-layer structure of tindioxide forms.

detect test example three:

As shown in Figure 3, the sample obtaining in embodiment 2 ~ 6 is carried out to X-ray diffractometer (XRD) analysis, find that five kinds of samples all have Tetragonal tindioxide structure, this shows it is no matter that (Fig. 3 a) or change Sn for low temperature ²⁺concentration (Fig. 3 b, c, d), or (Fig. 3 c, e), does not all affect the crystalline phase of tindioxide, just the sphere sizes of the tin dioxide nanocrystal forming is had to impact, but Sn to regulate the addition of urea ²⁺concentration the purity of tindioxide is had to impact, under high density, easily produce grey tin protoxide particle.Also illustrated that the three-dimensional layered multi-stage structure of tindioxide can successfully be prepared at low temperatures.

detect test example four:

As shown in Figure 4 and Figure 5, the sample obtaining in embodiment 2 ~ 6 is carried out to transmission electron microscope and high resolution transmission electron microscopy observation, in Fig. 4, clearly see the grown layered structure of nanometer sheet of five kinds of sample spherical surfaces, wherein Fig. 4 a has proved that the surperficial nanometer sheet of sample 2 also has length, consistent with the analysis of Fig. 2 a.In Fig. 5, can find that nanometer sheet length (is shown in Fig. 5 a, d) all in 200 about nanometers, thickness (is shown in Fig. 5 b) in 30 nanometer left and right, spacing of lattice is that Fig. 5 b, c, e) (are seen in 0.33 about nanometer, meet Tetragonal tindioxide (110) crystal face, illustrate that the stannic oxide nanometer sheet generating has preferential growth orientation, mainly along 110 crystal face growths, the tindioxide microballoon obtaining is positive Tetragonal, has illustrated that the variation of the amount of urea is an important influence factor to the formation of the layered multi-stage structure of controlling tindioxide simultaneously.

detect test example five:

As shown in Figure 6 and Figure 7, the tindioxide sample obtaining in embodiment 55 ageings were carried out to X-ray diffractometer analysis to its grey matter after 30 minutes, and from the position at peak, (see that Fig. 6 a) judges, what obtain is no longer pure phase tindioxide, have tin protoxide, and tin protoxide is main product.High Sn is described ²⁺concentration, easily causes impure.The tindioxide sample obtaining in embodiment 7 and 8 is carried out to scanning electron microscopic observation, that the reactor condition of large volume (is shown in Fig. 6 b) or first preoxidation (is shown in Fig. 6 c) in 24 hours no matter can observe clearly, all improve the required oxygen level of oxygenizement, but do not obtain more optimal tindioxide hierarchical multi-layer structure, illustrate that gentle oxygenizement is one of major influence factors to the formation of tindioxide multilayered structure.The tindioxide sample 8 obtaining in embodiment 8 is done to X-ray diffractometer and scanning electron microscopic observation, we find: before forming final product, first form tin protoxide and (seen Fig. 7 and Fig. 6 d, e), along with the increase of oxidization time, nanocrystallinely grow up gradually, and tin protoxide is oxidized to tindioxide, while reaching 15 hours, starts to form nano-sheet layered structure and (seen Fig. 6 f).

Claims

1. a preparation method for three-dimensional layered multi-stage flower-like tin dioxide microballoon, is characterized in that having following steps:

1) 0.8 ~ 1.0g urea is dissolved in the deionized water and ethanolic soln that volume ratio is 7:3 to preparation mixing solutions, the SnCl that is 98% by massfraction ₂2H ₂o, as presoma, prepares respectively Sn in mixing solutions ²⁺the suspension liquid of concentration 10,15 and 20 mM/L, then limit microwave-assisted light shaking mixing solutions, limit drips NaOH solution 0.8 ~ 1.0L of 6M/ml;