CN208340737U - The preparation facilities of the composite photo-catalyst of strontium titanates supported copper particle - Google Patents

Abstract

The utility model, which is created, provides a kind of preparation facilities of the composite photo-catalyst of strontium titanates supported copper particle, including constant pressure funnel, flask, magnetic stirring apparatus, the flask is equipped at least two bottlenecks, the bottleneck A of the liquid outlet of the constant pressure funnel and the flask is tightly connected, at least one bottleneck and atmosphere control device outside the bottleneck A of the flask are tightly connected, the inlet of the constant pressure funnel is detachably equipped with sealing-plug, the main body of the magnetic stirring apparatus is placed in below the flask, and the stirrer of the magnetic stirring apparatus is placed in the flask.The device that the utility model is created is simple and easily operated.

Description

The preparation facilities of the composite photo-catalyst of strontium titanates supported copper particle

Technical field

The invention belongs to photocatalysis technology field, and in particular to a kind of composite photocatalyst of strontium titanates supported copper particle Agent and preparation method thereof and device.

Background technique

Most of to be applied to light-catalysed semiconductor be wide bandgap semiconductor, can only utilize ultraviolet portion, and for can Light-exposed and infrared light is no any photoresponse.But ultraviolet light but only accounts for the 5% of solar energy, and visible light But accounting 43%.Therefore, visible light-responded catalysis material is developed to be of great significance.So far, scientific research personnel attempts Many methods, such as doping, surface treatment, dye sensitization etc., but these methods be also faced with it is unstable, inefficient Rate, it is at high cost the problems such as.By development in recent years, the absorption by coinage metal (gold, silver, copper) in visible light region is realized The visible light-responded of semiconductor material with wide forbidden band provides new methods and strategies for the above problem.However, most of research is still Be so around gold, silver noble metal be unfolded, and copper due to its oxidizable characteristic and rare people pay close attention to.It is previous studies have shown that What metal sensitization semiconductor composite photocatalytic water splitting reaction provided main drive is that metal band-to-band transition acts on (from d Track is to sp track), rather than local surface plasma resonance (LSPR) acts on.And the band-to-band transition threshold value of copper is only 1.9eV, far Band-to-band transition threshold value 2.4eV far below Au, so Cu under visible light should be more efficient for the driving of water decomposition reaction. Therefore, by the research for copper, the semiconductor composite of copper sensitization is prepared, is expected to solve photocatalyst compound material simultaneously At high cost and low efficiency two large problems.

Currently, the main problem that the semiconductor light-catalyst of load elemental copper faces is that copper is easily oxidized in air, So most researchers can not prepare the semiconductor catalyst of load elemental copper, or the load elemental copper prepared partly Conductor catalyst is not in time for participation light-catalyzed reaction also and has just been oxidized, and significantly limits copper simple substance in semiconductor light The application of catalytic field；Also, for the photocatalyst material of metal sensitization, the dimensional effect of metal nanoparticle is to light Catalytic efficiency plays a crucial role.

Summary of the invention

It is an object of the present invention to a kind of NEW TYPE OF COMPOSITE photochemical catalyst of strontium titanates supported copper particle and its systems Preparation Method and device, it is easy to operate using the method for the invention, reaction unit is easily controllable, the NEW TYPE OF COMPOSITE being prepared Photochemical catalyst activity with higher.

The invention provides firstly a kind of NEW TYPE OF COMPOSITE photochemical catalyst, with strontium titanate nanoparticles (SrTiO₃) it is to carry Body, copper nano particles (Cu) are carried on strontium titanate nanoparticles；Wherein, the load capacity of Cu is 0.01wt%-5wt%, excellent It is selected as 0.2wt%-1.0wt%, more preferably (0.5 ± 0.1) wt%；The particle size of Cu is 0.1-50nm, preferably 2- 10nm, more preferably (4 ± 1) nm.

The invention additionally provides the method for preparing above-mentioned composite photo-catalyst, includes the following steps: to receive strontium titanates Rice grain, water and hole sacrifice agent are hybridly prepared into the first premixed liquid；In vacuum or inert gas, under stirring condition, by sulphur Sour copper solution is mixed with the first premixed liquid point n times, n >=1, so that mixed liquor is carried out light under illumination condition after mixing every time Deposition reaction certain time, total amount of copper that n times mixing is added are the targeted loads amount of copper；Collect product after the reaction was completed to obtain the final product.

Wherein, concentration of the strontium titanate nanoparticles in the first premixed liquid be 0.0001-0.1mol/L, described first The volume ratio of water and hole sacrifice agent is (3-5) in premixed liquid: 1, the concentration of the copper-bath is 0.0001-0.1mol/ L.The reaction solution of low concentration is conducive to the abundant progress of light deposition reaction.

Wherein, the effect of the hole sacrifice agent (hole sacrifical) is consumption hole, is inhibited in photocatalytic process Electron-hole is compound, may include methanol, lactic acid, ascorbic acid etc..

Wherein, n is preferably 2-20, preferably 4-8.

Wherein, the light deposition reaction condition is 300 ± 10W xenon lamp, wavelength 200-800nm, reaction time overall length are 4- The amount of 8h, the copper that each reaction time is added according to each mixing are divided in portion.For example, when the amount that copper is added in certain mixing is Targeted loads amount 1/5 when, this time mixing after light deposition react time be also the 1/5 of reaction time overall length.

Preferably, the amount for the copper-bath that mixing is added every time is equal, and the light deposition reaction time is identical after mixing every time.

Wherein, the strontium titanate nanoparticles can be bought, can also be preferably using the polymerization complexometry preparation of improvement It obtains, includes the following steps: to prepare monohydrate potassium, Strontium dichloride hexahydrate, butyl titanate respectively in ethylene glycol monomethyl ether Lysate, each lysate is mixed and added into ethylene glycol and mixes to obtain mixed liquor, the solvent of mixed liquor is evaporated and is sintered organic Skeleton, then respectively 300 ± 20 DEG C and 500 ± 20 DEG C at a temperature of respectively keep the temperature 2-6h, ground after cooling to obtain the final product.

The invention additionally provides the device for preparing above-mentioned composite photo-catalyst, including constant pressure funnel, flask, magnetic force stir Device is mixed, the flask is equipped at least two bottlenecks, and the liquid outlet of the constant pressure funnel and the bottleneck A of the flask are tightly connected, At least one bottleneck and atmosphere control device outside the bottleneck A of the flask are tightly connected, and the inlet of the constant pressure funnel can Disassembly is equipped with sealing-plug, and the main body of the magnetic stirring apparatus is placed in below the flask, and the stirrer of the magnetic stirring apparatus is set In in the flask.

Wherein, be equipped with liquid storage pipe between the inlet and liquid outlet of the constant pressure funnel, the liquid storage pipe and liquid outlet it Between be set as tubule section, the tubule section is equipped with liquid switch, and the side of the liquid storage pipe is also communicated with side pipe, the side pipe Top be connected to the top of liquid storage pipe, the bottom of the side pipe is connected to the tubule section below liquid switch.

Wherein, the side of the flask is wholely set as that can match with light source, take the photograph light ray parallel in the aperture of plane Enter, avoids the light losses such as light leakage, refraction.

Wherein, the bottleneck A of the flask is angularly disposed, and the constant pressure funnel is supported by liftable bracket, Neng Goushi The stabilization of existing device.

Wherein, the atmosphere control device is to make to reach anaerobic state in device, and copper in reaction process is avoided to aoxidize Device, illustrative example can be individual vacuum evacuation device, or coefficient vacuum evacuation device and inertia Gas input device makes to reach vacuum or inert gas shielding condition in device.

Compared with prior art, the invention has the advantage that preparation method and device are simple, and easily operated. The continuous regulation of copper particle size can be conveniently realized, and solves the semiconductor catalysis that can not prepare load elemental copper Agent, or the semiconductor catalyst of load elemental copper prepared do not have enough time also participating in what light-catalyzed reaction had just been oxidized Problem.In the case where loading identical mass fraction copper simple substance, the Cu/SrTiO of certain copper nano particles size₃Composite photocatalyst There is agent material high visible light water decomposition to produce hydrogen activity.And production cost is low, meets actual production demand.

Detailed description of the invention

The attached drawing for constituting a part of the invention is used to provide to further understand the invention, present invention wound The illustrative embodiments and their description made are used to explain the present invention creation, do not constitute the improper restriction to the invention.? In attached drawing:

Fig. 1 is the structural schematic diagram for the device that the invention prepares composite photo-catalyst.

Fig. 2 is the XRD diffracting spectrum of strontium titanate nanoparticles.

Fig. 3 is 0.5wt% for the load capacity in copper, the Cu/SrTiO through different deposition step numbers₃TEM figure.

Fig. 4 is 0.5wt% for the load capacity in copper, the Cu/SrTiO through different deposition step numbers₃UV-vis figure.

Fig. 5 is 0.5wt% for the load capacity in copper, the Cu/SrTiO through different deposition step numbers₃With light application time variation Hydrogen output.

Fig. 6 is the load capacity in embodiment 7-9 in different Cu, the Cu/SrTiO through different deposition step numbers₃Hydrogen-producing speed.

Fig. 7 is to produce hydrogen activity under different loads object to compare.

Specific embodiment

It creates, the invention is carried out in order to better understand the present invention below with reference to specific the drawings and specific embodiments Further description.The load capacity of copper described in the invention is the percentage that copper accounts for strontium titanates quality.

One, the preparation of device

By constant pressure funnel 1, flask 2, magnetic stirring apparatus 3 according to assembling is sealed shown in Fig. 1, the wherein use of flask 2 can With three-necked flask.The liquid outlet 11 of constant pressure funnel 1 and the angularly disposed bottleneck A 21 of flask 2 are tightly connected, and flask 2 is in addition Two bottlenecks and atmosphere control device are tightly connected.When flask 2 has extra bottleneck or atmosphere control device only can When being connect with a bottleneck, encapsulation process can be done to remaining bottleneck, be closed for example, by using sealing-plug etc., constant pressure funnel 1 inlet 12 is detachably equipped with sealing-plug 13.The atmosphere control device can be individual vacuum evacuation device, for anti- At once so that device is in vacuum state, an inert gas input unit can also be added, poured after evacuation into device Inert gas (nitrogen, argon gas etc.), makes device be in inert gas shielding state.The inlet 12 and liquid outlet of constant pressure funnel 1 It is equipped with liquid storage pipe 14 between 11, tubule section 15 is set as between liquid storage pipe 14 and liquid outlet 11, tubule section 15 is opened equipped with liquid 16 are closed, the side of liquid storage pipe 14 is also communicated with side pipe 17, and the top of side pipe 17 is connected to the top of liquid storage pipe 14, the bottom of side pipe 17 Portion is connected to the tubule section 15 of 16 lower section of liquid switch.The side of flask 2 is wholely set as in the aperture 22 of plane, can be with light Source matching, takes in light ray parallel, avoids the light losses such as light leakage, refraction.The main body of magnetic stirring apparatus 3 is placed under the flask 2 Side, the stirrer 31 of magnetic stirring apparatus 3 is placed in flask 2, convenient for the lasting stirring under vacuum or inert gas conditions.Constant pressure leakage Bucket 1 is supported by liftable bracket 4, the stabilization of realization device.

Two, the preparation of strontium titanate nanoparticles

The monohydrate potassium for weighing 60g is dissolved in the ethylene glycol monomethyl ether of 60mL, 50 DEG C of heating water baths, and 500 revs/min Clock stirs 30 minutes.The Strontium dichloride hexahydrate of 4.4g is dissolved in the ethylene glycol monomethyl ether of 20mL, 500 revs/min, stirring 10 Minute.The butyl titanate for weighing 5.6mL is dissolved in the ethylene glycol monomethyl ether of 20mL, 500 revs/min, is stirred 10 minutes.In object Matter dissolves after mixing evenly, solution of tetrabutyl titanate is poured into strontium chloride solution, stir about 20 minutes, until collosol state, then This sol liquid is poured into monohydrate potassium solution, stirs 10 minutes, after mixing, be added 5mL without water glycol, It is again stirring for 10 minutes.Finally obtained solution is transferred in crucible, is placed in baking oven, is first heat-treated 20 hours for 120 DEG C, Solvent is evaporated, then 130 DEG C are heat-treated 20 hours, are sintered organic backbone, take out after condensation.Condensate is put into batch-type furnace, it is empty Under atmosphere is enclosed, 300 DEG C are kept for 3 hours, are warming up to 500 DEG C and are kept for 5 hours, are ground after being cooled to room temperature.Pass through above series of Strontium titanate nanoparticles are finally made in step.

Three, Cu/SrTiO is prepared₃Composite photo-catalyst

The preparation of composite photo-catalyst is carried out using above-mentioned ready device.By strontium titanates nanometer made from 0.2g The methanol of grain, the water of 220ml and 50ml is placed in flask 2, and opening magnetic stirring apparatus 3 is in the solution in flask 2 always Uniform stirring state.Cupric sulfate pentahydrate is weighed according to 20 times of the targeted loads amount of Cu and is configured to 200ml solution, when taking wherein When 10ml solution, the targeted loads amount of as Cu.Cupric sulfate pentahydrate solution is moved in constant pressure funnel 1 by liquid-transfering gun, then The inlet 12 of constant pressure funnel 1 is stoppered into sealing with sealing-plug 13.Opening that may be present in device is sealed, atmosphere control is opened Device processed makes to reach vacuum or inert gas shielding state in device.The outside that device is encased with masking foil reserves the use of aperture 22 In receiving light source, light source is 300 ± 10W xenon lamp, wavelength 200-800nm.In multiple mixing and light deposition reaction process, with X wt% indicates that the targeted loads amount of Cu, 10ml cupric sulfate pentahydrate solution point n times carry out mixing and light deposition reaction, mix every time The amount that cupric sulfate pentahydrate solution is added is x/n, and the total duration of light deposition reaction is t, the when a length of t/n of each light deposition reaction. In mixed once, liquid switch 16 is opened, cupric sulfate pentahydrate solution is oblique by the liquid outlet 11 of constant pressure funnel 1 and flask 2 To the bottleneck A 21 of setting flow into flask 2 in, control single influx be x/n, closing liquid switch 16, then opening light source into The reaction of row light deposition, when a length of t/n, repeat the above steps until n times reaction terminates.Metatitanic acid under full light action, in flask 2 Strontium semiconductor grain can generate electrons and holes pair, the electrons of generation allow inflow cupric sulfate pentahydrate solution in copper ion reduction Strontium titanates semiconductor surface is deposited at copper simple substance.

Using the above method, the targeted loads amount with Cu is 0.5wt%, and n is respectively 1,2,4,8,12,20, and light deposition is total Shi Changwei 4h is preparation condition, obtains sample Cu/SrTiO respectively as embodiment 1-6₃-PD1、Cu/SrTiO₃-PD2、Cu/ SrTiO₃-PD4、Cu/SrTiO₃-PD8、Cu/SrTiO₃-PD12、Cu/SrTiO₃-PD20。

Using the above method, the targeted loads amount with Cu is respectively 0.2wt%, 0.5wt%, 1.0wt%, n is respectively 1, 2,3, light deposition total duration is that 4h is preparation condition, obtains series of samples 0.2%Cu/SrTiO respectively as embodiment 7-9₃、 0.5%Cu/SrTiO₃, 1.0%Cu/SrTiO₃。

Using the above method, by loaded article SrTiO₃Replace with TiO₂Cu/TiO is prepared₂It is as a comparison sample, comparison Evaluate the production hydrogen activity under its visible light conditions.

Four, evaluation of result

1, the characterization of strontium titanate nanoparticles

Fig. 2 is the XRD diffracting spectrum for preparing strontium titanates.As can be seen that the characteristic diffraction peak of strontium titanates from the map of XRD Can be corresponding with standard PDF card well, wherein the diffraction maximum that 2 angles θ are 39.96 °, 46.47 ° and 57.79 ° respectively corresponds SrTiO₃(111), (200) and (211) crystal face, this illustrates that strontium titanates obtained is pure phase.

2、Cu/SrTiO₃Microstructure morphology characterization

Fig. 3 is the Cu/SrTiO that 0.5wt% copper list carrying capacity difference deposits step number₃TEM map.Copper as can be seen from Figure 3 When load capacity is 0.5%, as the step number of light deposition increases, obtained copper particle size is gradually increased.Light deposition 1 time The size of corresponding copper particle is 2.8nm, and the size of light deposition 2 times corresponding copper particles is 3.3nm, and light deposition 4 times corresponding The size of copper particle is 3.9nm, and the size of light deposition 8 times corresponding copper particles is 5.1nm, light deposition 12 times corresponding copper particles Size be 6.2nm, the sizes of light deposition 20 times corresponding copper particles is 7.7nm.From subsequent evaluation as can be seen that light deposition In the case that step number is 4 times, Cu/SrTiO₃Go out hydrogen activity it is best, reach 15.3 μm of ol/h.Therefore by reacting light deposition The size of effectively regulation and control supported copper particle is capable of in the adjustment of number, and manual intervention produces hydrogen activity.

3, absorption spectrum

Fig. 4 gives five groups of 0.5wt% copper load capacity, the Cu/SrTiO of difference deposition step number₃And pure strontium titanates exists The UV-visible-near infrared absorption figure of 500-800nm wavelength.It can be seen from the figure that pure phase strontium titanates is in visible light Region does not have any absorption, this with its broad-band gap be it is directly related, the band gap of 3.2eV causes strontium titanates that cannot absorb can It is light-exposed, and ultraviolet portion can only be utilized.And after having loaded copper particle, there is an apparent absorption in visible light region Peak, with the increase of light deposition step number, there is a more apparent red shift trend in the position of sample SPR characteristic peak, absorption peak Position becomes 623.5nm from 610nm, with the increase of metal particle size, LSPR characteristic peak red shift.

4, photocatalytic water splitting produces hydrogen activity evaluation

Active evaluation has been carried out to sample respectively using Japanese Shimadzu GC-2014C gas chromatograph.Specific steps are such as Under: it weighs 0.2g sample and 50ml methanol (as hole acceptor) is put into water decomposition reactor, 220mL water is added.With 300 ± The xenon lamp of 10W filters off ultraviolet light, wavelength 420-800nm as light source, with the filter plate that cutoff wavelength is 420nm.Photocatalysis During reaction, a sample is taken every 1h, the yield of hydrogen is calculated, carries out the evaluation of photocatalysis performance.

Fig. 5 is 0.5wt% copper list carrying capacity, the Cu/SrTiO of difference deposition step number₃The variation of photocatalytic water splitting hydrogen output Figure.Can be more obvious from figure find out, with the increase of light deposition number, Cu/SrTiO₃Activity there is one first to increase Downward trend afterwards reaches active optimum value when light deposition 4 times, about per hour 15.3 μm of ol.

Fig. 6 is different Cu load capacity, the Cu/SrTiO of difference deposition step number₃Photocatalytic water splitting hydrogen-producing speed figure.From figure In as can be seen that no matter under any light deposition step number, mass fraction is that the sample of 0.5wt% copper load capacity is all shown most Good activity.

Fig. 7 is the composite photo-catalyst Cu/SrTiO of different loads produce product₃And Cu/TiO₂Photocatalytic water splitting produce hydrogen Expression activitiy.The load capacity of Cu is 0.5wt%, and catalyst amount is 0.2g, it is seen that it is 420-800nm that light, which produces hydrogen condition,. It can be seen that SrTiO₃With more being matched with Cu and forbidden bandwidth preferably and good stability, degraded using solar energy Pollutant, have many advantages, such as it is without secondary pollution, efficient, energy saving, compared with TiO₂With greater advantages.

The foregoing is merely the preferred embodiments of the invention, are not intended to limit the invention creation, all at this Within the spirit and principle of innovation and creation, any modification, equivalent replacement, improvement and so on should be included in the invention Protection scope within.

Claims (5)

1. a kind of preparation facilities of the composite photo-catalyst of strontium titanates supported copper particle, which is characterized in that including constant pressure funnel (1), flask (2), magnetic stirring apparatus (3), the flask (2) are equipped at least two bottlenecks, the liquid outlet of the constant pressure funnel (1) (11) with the bottleneck A (21) of the flask (2) be tightly connected, at least one bottleneck of the bottleneck A (21) of the flask (2) outside with Atmosphere control device is tightly connected, and the inlet (12) of the constant pressure funnel (1) is detachably equipped with sealing-plug (13), the magnetic force The main body of blender (3) is placed in below the flask (2), and the stirrer (31) of the magnetic stirring apparatus (3) is placed in the flask (2) in.

2. the preparation facilities of the composite photo-catalyst of strontium titanates supported copper particle according to claim 1, which is characterized in that Between the inlet (12) and liquid outlet (11) of the constant pressure funnel (1) be equipped with liquid storage pipe (14), the liquid storage pipe (14) with go out It is set as between liquid mouth (11) tubule section (15), the tubule section (15) is equipped with liquid switch (16), the liquid storage pipe (14) Side be also communicated with side pipe (17), the top of the side pipe (17) is connected to the top of liquid storage pipe (14), the side pipe (17) Bottom be connected to the tubule section (15) below liquid switch (16).

3. the preparation facilities of the composite photo-catalyst of strontium titanates supported copper particle according to claim 1, which is characterized in that The side of the flask (2) is wholely set as in the aperture of plane (22).

4. the preparation facilities of the composite photo-catalyst of strontium titanates supported copper particle according to claim 1, which is characterized in that The bottleneck A (21) of the flask (2) be it is angularly disposed, the constant pressure funnel (1) by liftable bracket (4) support.

5. the preparation facilities of the composite photo-catalyst of strontium titanates supported copper particle according to claim 1, which is characterized in that The atmosphere control device is individual vacuum evacuation device or coefficient vacuum evacuation device and inert gas input dress It sets.