CN102543457B - Preparation method of zinc sulfide (ZnS)/cadmium telluride (CdTe) quantum dot sensitization titanium dioxide (TiO2) nano film - Google Patents

Preparation method of zinc sulfide (ZnS)/cadmium telluride (CdTe) quantum dot sensitization titanium dioxide (TiO2) nano film Download PDF

Info

Publication number
CN102543457B
CN102543457B CN201210032484.9A CN201210032484A CN102543457B CN 102543457 B CN102543457 B CN 102543457B CN 201210032484 A CN201210032484 A CN 201210032484A CN 102543457 B CN102543457 B CN 102543457B
Authority
CN
China
Prior art keywords
cdte
film
quantum dot
tio
zns
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CN201210032484.9A
Other languages
Chinese (zh)
Other versions
CN102543457A (en
Inventor
杜荣归
张娟
朱燕峰
郭亚
林昌健
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Xiamen University
Original Assignee
Xiamen University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Xiamen University filed Critical Xiamen University
Priority to CN201210032484.9A priority Critical patent/CN102543457B/en
Publication of CN102543457A publication Critical patent/CN102543457A/en
Application granted granted Critical
Publication of CN102543457B publication Critical patent/CN102543457B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y02E10/549—Organic PV cells

Abstract

The invention discloses a preparation method of zinc sulfide (ZnS)/cadmium telluride (CdTe) quantum dot sensitization titanium dioxide (TiO2) nano film, and relates to a TiO2 nano film. The method comprises the following steps: preparing a titanium matrix sample, preparing a TiO2 nano-tube array film at the surface of the sample, preparing a CdTe quantum dot sensitization TiO2 nano film, and finally preparing a ZnS/CdTe quantum dot sensitization TiO2 nano film. Under irradiation of white light, the film enables an electrode potential of connected metals like stainless steel to be greatly reduced in corrosive medium, and can protect good cathode of metals like stainless steel continuously for a long time in a dark state. And the nano film prepared by using the method has an efficient photoproduction cathode protection effect.

Description

The preparation method of the quantum dot sensitized TiO2 nano thin-film of ZnS/CdTe
Technical field
The present invention relates to a kind of TiO 2nano thin-film, especially relates to the quantum dot sensitized TiO of a kind of ZnS/CdTe 2the preparation method of nano thin-film.
Background technology
Semiconductor titanium dioxide (TiO 2) there is good PhotoelectrochemicalProperties Properties, be widely used in the fields such as solar cell, photocatalytic degradation pollutant and photolysis water hydrogen.Someone reports, when the TiO under illumination 2film is connected with metal by wire, and the light induced electron of generation is transferred to metal surface by wire, and its electrode potential is reduced, and can play to metal the effect of cathodic protection, i.e. so-called photoproduction cathodic protection.Therefore, TiO 2the preparation of film and the application in corrosion of metals control have caused corrosion research person's great attention.
Although theoretically, photoproduction cathodic protection effect utilizes TiO 2semi-conductive photoelectric properties, do not consume electric energy, and more environmental protection has tempting application prospect; But because titanium dioxide is the semiconductor (3.2eV) of broad stopband; all can not effectively absorb for most visible ray; produced simultaneously light induced electron-hole is fast to the recombination velocity under dark state, and photoproduction cathodic protection does not act on while thering is no illumination and is difficult to maintain.For above problem, aspect photoproduction cathodic protection research, still needing and carrying out a large amount of research at present.Aspect photocatalysis and solar cell research, some has obtained good progress, for example, and for improving TiO 2to the utilance of sunlight, make its absorption region expand to visible region, as to TiO 2film adulterate (8, Tu Y F, Huang S Y, SangJ P.et al.Preparation of Fe-doped TiO 2nanotube arrays and their photocatalytic activities undervisible light[J] .Materials Research Bulletin, 2010,45 (2): 224-229; 9, Nakamura R, Tanaka T, Nakato Y.Mechanism for visible light responses in anodic photocurrents at N-doped TiO 2filmelectrodes[J] .Journal of Physical Chemistry B, 2004,108 (30): 10617-10620) or sensitization processing etc. (10, Zhu G, Xu T, Lv T A, et al.Graphene-incorporated nanocrystalline TiO 2films for CdS quantumdot-sensitized solar cells[J] .Journal of Electroanalytical Chemistry, 2011,650 (2): 248-251; 11, XuX Q, Xu G.Electrochemical impedance spectra of CdSe quantume dots sensitized nanocrystallineTiO 2solar cells[J] .Science China-Chemistry, 2011,54 (1): 205-210), go back the semiconductor (WO of the different energy levels of handlebar 3(12, Subasri R, Shinohara T, Mori K.TiO 2-based photoanodes for cathodic protection of copper[J] .Journal of the Electrochemical Society, 2005,152 (3): B105-B110; 13, Zhou M J, Zeng ZO, Zhong L.Energy storage ability and anti-corrosion protection properties of TiO 2-SnO 2system[J] .Mater.Corros, 2010,61 (4): 324-327), SnO 2(14, Tetsu T, Shuichi S, Yoshihisa O, et al.TiO 2-WO 3photoelectrochemical Anticorrosion Systemwith an Energy Storage Ability[J] .Chem.Mater, 2001,13:2838-2842; 15, Zhou M J, Zeng Z O, Zhong L.Photogenerated cathode protectionproperties of nano-sized TiO 2/ WO 3coating[J] .Corrosion Science, 2009,51 (6): 1386-1391) etc.) and coupling TiO 2, as the storage vault of electronics under illumination, slow down the right recombination rate in light induced electron-hole, and under dark state, these electronics are transferred to metal, continue within a certain period of time cathodic protection effect.
Quantum dot sensitized processing, can be used as a kind of to TiO 2film carries out the method for modification.Because the size dimension of quantum dot can regulate, therefore can increase substantially TiO 2to the utilance of sunlight.Meanwhile, because optical excitation can produce multipair electron-hole pair in quantum dot, therefore can strengthen well again TiO 2photoelectric respone; In addition, due to quantum spot semiconductor and TiO 2form special hierarchic structure (16, Chi C F, Cho H W, Teng H S, et al.Energy level alignment, electron injection, and charge recombination characteristics in CdS/CdSe cosensitized TiO 2photoelectrode[J] .Applied Physics Letters, 2011,98 (1)), therefore may make the TiO processing through sensitization 2under dark state, also there is certain cathodic protection effect.
CdTe is as a kind of desirable photoelectric conversion material, and its energy gap is 1.47eV, mates well, to TiO with solar spectrum 2sensitization processing, may have better photoelectric respone.At present, the preparation of CdTe is mainly in acid solution, adopt chemical bath deposition method (17, Gao X F, Li H B, Sun W T, et al.CdTe Quantum Dots-Sensitized TiO 2nanotubeArray Photoelectrodes[J] .Journal of Physical Chemistry C, 2009,113 (18): 7531-7535), electrodeposition process (18, Seabold J A, Shankar K, Wilke R H T, et al.Photoelectrochemical Properties ofHeterojunction CdTe/TiO 2electrodes Constructed Using Highly Ordered TiO 2nanotube Arrays[J] .Chemistry of Materials, 2008,20 (16): 5266-5273) or sol-gal process (19, Li Y S, Jiang F L, Xiao Q, et al.Enhanced photocatalytic activities of TiO 2nanocomposites doped with water-solublemercapto-capped CdTe quantum dots[J] .Applied Catalysis B-Environmental, 2010,101 (1-2): 118-129) etc., method more complicated.About the report of preparation method in alkaline solution relatively lacks.In addition, the poor stability of CdTe quantum dot under illumination, be always restriction its application bottleneck (20, Bang J H, Kamat P V.Quantum DotSensitized Solar Cells.A Tale of Two Semiconductor Nanocrystals:CdSe and CdTe[J] .ACS Nano, 2009,3 (6): 1467-1476).
Summary of the invention
The object of the invention is to the TiO for existing preparation 2film photoelectric efficiency is lower, under dark state, there is no photoproduction cathodic protection effect, and quantum dot problem such as unstable under illumination, and a kind of quantum dot sensitized TiO of ZnS/CdTe with efficient photoproduction cathodic protection effect is provided 2the preparation method of nano thin-film.
The present invention includes following steps:
1) prepare titanium matrix sample;
2) prepare TiO at titanium matrix specimen surface 2film of Nano tube array, the described titanium surface TiO of preparing 2nanotube can adopt anode oxidation method, and concrete grammar is as follows: by NH 4f is dissolved in deionized water, adds glycerol, obtains mixed solution, using platinum as to electrode, and at mixed solution Anodic Oxidation, then by sample calcining, then cool to room temperature with the furnace, make TiO2 film of Nano tube array at titanium matrix specimen surface;
3) prepare the quantum dot sensitized TiO of CdTe 2nano thin-film: the quantum dot sensitized TiO of described preparation ZnS/CdTe 2nano thin-film adopts constant pressure impulse electrodeposition process, and concrete grammar is as follows: in step 2) TiO that obtains 2film of Nano tube array surface deposition CdTe quantum dot, by Na 2teO 3solution, CdSO 4with nitrilotriacetic acid trisodium (Na 3nTA) mix after as reaction solution, use H 2sO 4regulating the pH of reaction solution is 8～9, adopts three-electrode system, with TiO 2film of Nano tube array is work electrode, and Pt is to electrode, and saturated calomel electrode is reference electrode, carries out constant pressure impulse electro-deposition on chem workstation, makes the quantum dot sensitized TiO of CdTe 2nano thin-film;
4) prepare the quantum dot sensitized TiO of ZnS/CdTe 2nano thin-film: by step 3) the quantum dot sensitized TiO of CdTe that makes 2nano thin-film is first at CdCl 2in solution, soak, dry after annealing processing, make CdTe/TiO 2composite membrane; Adopt again circulatory maceration at CdTe/TiO 2composite membrane surface deposition ZnS, concrete grammar is as follows: by the CdTe/TiO that contains of preparation 2the sample of composite membrane is first soaked in Zn 2+ethanolic solution in (1～2) min, then use alcohol flushing; Be placed in again S 2-methanol solution in soak (1～2) min, use again alcohol flushing, obtain the quantum dot sensitized TiO of ZnS/CdTe 2nano thin-film.
In step 1) in, the described concrete grammar of preparing titanium matrix sample can be: using titanium foil as titanium matrix, by after the polishing of titanium matrix surface, clean, obtain titanium matrix sample; Described titanium matrix can be rectangle titanium matrix, and length is (1.0～1.5) cm, and wide is (1.0～1.5) cm, and thickness is (0.05～0.15) mm; The Ti content of described titanium foil is best more than 99.9%; Described polishing can adopt 400～No. 1500 silicon carbide paper polishings, and described cleaning can be cleaned (5～10) min at acetone, absolute ethyl alcohol and deionized water for ultrasonic ripple successively.
In step 2) in, described NH 4the proportioning of F, deionized water and glycerol can be (4.5～5) gNH 4f: (300～400) mL deionized water: (500～600) mL glycerol, wherein NH 4f calculates in mass, and deionized water and glycerol are calculated by volume; Described anodised voltage can be (20～30) V, and the anodised time can be (20～30) min; The condition of described calcining can be sample is placed in Muffle furnace to calcining (1.5～2.0) h at (450～550) ℃.
In step 3) in, described Na 2teO 3the concentration of solution can be (2～8) mmol/L, described CdSO 4concentration can be (0.01～0.05) mol/L; The concentration of described nitrilotriacetic acid trisodium can be (0.02～0.08) mol/L; Described H 2sO 4concentration can be (0.05～0.20) mol/L; Described Na 2teO 3preparation method can be: by (0.350～0.450) g TeO 2powder and (0.100～0.300) g NaOH join in (400～600) mL deionized water, and (2～5) h that refluxes at 70 ℃, is cooled to room temperature, obtains Na 2teO 3; Described pulse parameter of carrying out constant pressure impulse electro-deposition on chem workstation can be: the burst length is (0.05～0.20) s, pulse-off interval time is (0.5～1.5) s, pulse electromotive force is (1.3～-1.5) V, and the circulation number of turns is (40～100).
In step 4) in, described CdCl 2concentration can be (0.2～0.8) mol/L, the time of described immersion can be 0.5～5min; The condition of described oven dry can be dries (3～8) min in the baking oven of (60～80) ℃; The condition of described annealing in process can be annealing in process (25～35) min at (350～450) ℃; In order to improve the stability of prepared smooth anode, described employing circulatory maceration is at CdTe/TiO 2composite membrane surface deposition ZnS (3～5) capable of circulation is inferior.
Below provide the quantum dot sensitized TiO of ZnS/CdTe 2the method of testing of the photoproduction cathodic protection effect of nano thin-film:
Adopt the double-electrolyzer system of photoelectrolytic cell and corrosion electrolytic cell composition.The quantum dot sensitized TiO of ZnS/CdTe 2nano thin-film is light anode, is placed in photoelectrolytic cell, and wherein electrolyte is (0.3～0.6) mol/LNa 2sO 4+ (0.3～0.6) mol/L HCOOH solution, using (0.1～0.3) mol/LNaOH regulator solution pH is (9～10).Corrosion electrolytic cell is three-electrode system, and work electrode is protected metal, is Pt electrode to electrode, and reference electrode is saturated calomel electrode (SCE), take (0.1～1.0) mol/L NaCl as medium solution.Light anode is connected by wire with protected metal electrode, and photoelectrolytic cell is connected by salt bridge (containing the agar of 1.0mol/LKCl) with corrosion electrolytic cell.When illumination, using 150W high pressure Xe lamp as white light source, direct irradiation is TiO in photoelectrolytic cell 2composite membrane surface.
The present invention first utilizes anode oxidation method to prepare TiO 2nanotube, adopts constant pressure impulse electrodeposition process at the compound CdTe quantum dot of nanotube surface, and by the film making at CdCl 2in solution, soak after a period of time annealing in process under high temperature, to strengthen the stability of quantum dot.Adopt the coated ZnS shell of the film surface of circulatory maceration after annealing in process; under white light; this film can make the electrode potential of the metals such as stainless steel in Korrosionsmedium connecting significantly decline, and also can maintain for a long time the good cathodic protection effect of the metals such as stainless steel in the time of dark state.
Below provide beneficial effect of the present invention:
The quantum dot sensitized TiO of ZnS/CdTe prepared in accordance with the present invention 2nano thin-film, has all even complete features of coating, can be used as light anode, and the electrode potential of the protected metal connecting is significantly declined, and the more important thing is and in the time of dark state, still can maintain for a long time good cathodic protection effect.Quantum dot sensitized film prepared by the inventive method is after annealing in process, and the defect concentration on quantum dot surface reduces, and degree of crystallinity improves, thereby stability strengthens.At 0.5mol/L Na 2sO 4in+0.5mol/LHCOOH (pH=9.6) solution, when white light, film after annealing in process, can make 403 stainless steels in 0.5mol/LNaCl solution (stainless steel that a kind of corrosion resistance is relatively poor) the electrode potential decline 450mV being attached thereto, lower than stainless spontaneous potential.And stopping after illumination, though stainless steel electrode current potential has rising, but still lower than the about 200mV of stainless spontaneous potential, under dark state, also there is good photoproduction cathodic protection effect.And without the film of annealing in process, even if be coated ZnS shell, after illumination 2h, quantum dot has decomposed substantially completely.
Accompanying drawing explanation
In the constant pressure impulse electro-deposition method that Fig. 1 adopts for the embodiment of the present invention 1, apply voltage system schematic diagram.In Fig. 1, abscissa is time t (s), and ordinate is voltage voltage (V); Wherein, t onfor the burst length, t offfor pulse turn-off time, deposition represents deposition, and diffusion and accumulation of ions represents diffusion and the gathering of ion.
Fig. 2 is the quantum dot sensitized TiO of ZnS/CdTe prepared by the application embodiment of the present invention 1 2nano thin-film surface topography (SEM figure).In Fig. 2, scale is 100nm.
Fig. 3 is the quantum dot sensitized TiO of ZnS/CdTe prepared by the application embodiment of the present invention 1 2the photoelectricity flow graph of nano thin-film.In Fig. 3, abscissa is wavelength X/nm, and ordinate is photoelectric current Photocurrent (nA).
Fig. 4 be in the embodiment of the present invention 1 403 stainless steels in 0.5mol/L NaCl solution with the quantum dot sensitized TiO of ZnS/CdTe 2nano thin-film light anodic bonding, illumination front and back are electrode potential temporal evolution (light on represents illumination, and light off represents to close light source, i.e. dark state) in 0.5mol/L NaCl solution.In Fig. 4, abscissa is time t (h), and ordinate is current potential E (V vs.SCE).
Fig. 5 is the quantum dot sensitized TiO of ZnS/CdTe prepared by the application embodiment of the present invention 2 2nano thin-film surface topography (SEM figure).In Fig. 5, scale is 100nm.
Fig. 6 is the quantum dot sensitized TiO of ZnS/CdTe prepared by the application embodiment of the present invention 2 2the photoelectricity flow graph of nano thin-film.In Fig. 6, abscissa is wavelength X/nm, and ordinate is photoelectric current Photocurrent (nA).
Fig. 7 is 403 stainless steels and quantum dot sensitized nano thin-film light anodic bonding in the embodiment of the present invention 2, before and after illumination in 0.5mol/L NaCl solution electrode potential temporal evolution (light on represents illumination, light off represents to close light source, i.e. dark state).In Fig. 7, abscissa is time t (h), and ordinate is current potential E (V vs.SCE).
Embodiment
The present invention is further illustrated in connection with accompanying drawing for following examples.
Embodiment 1
According to technique scheme (concrete steps), the quantum dot sensitized TiO of preparation ZnS/CdTe 2nano thin-film, and testing film as light anode to 403 stainless cathodic protection effects.
Take the thick rectangle pure titanium foil of 0.1mm as sample, its long 15mm, wide is 10mm.Specimen surface, after 400～No. 1500 silicon carbide paper polishings, is taken up in order of priority and is cleaned 10min at acetone, absolute ethyl alcohol and deionized water for ultrasonic ripple.
Take 4.5g NH 4f, is dissolved in 333mL deionized water, adds 500mL glycerol, mixes.Under room temperature, do electrode with platinum, in above-mentioned solution, anodic oxidation 30min under 20V voltage.Then sample is placed on and in Muffle furnace, at 450 ℃, calcines 2h and cool to room temperature with the furnace, make TiO on Ti surface 2film of Nano tube array.
Adopt constant pressure impulse electrodeposition process, use Autolab PGSTAT30 electrochemical workstation, first at above-mentioned TiO 2film of Nano tube array surface deposition CdTe quantum dot, 5mmol/L Na 2teO 3solution, 0.02mol/L CdSO 4and 0.05mol/LNa 3nTA (nitrilotriacetic acid trisodium) mixes as reaction solution, with 0.1mol/L sulfuric acid regulation solution pH be 8.3.Wherein Na 2teO 3preparation method as follows: by 0.399g TeO 2powder and 0.200g NaOH join in 500mL deionized water, and the 3h that refluxes at 70 ℃, is cooled to room temperature.Burst length is 0.15s, and pulse turn-off time is 1s, and pulse electromotive force is-1.5V that the circulation number of turns is 70.Its constant pressure impulse electro-deposition schematic diagram as shown in Figure 1.
In order effectively to reduce the surface defect density of quantum dot, by the film of Nano tube array preparing at 0.5mol/L CdCl 2in solution, soak 1min, in the baking oven of 70 ℃, dry 5min, then at 400 ℃ annealing in process 30min.
In order to improve the stability of prepared smooth anode, adopt circulatory maceration at CdTe/TiO 2electrode surface deposition ZnS.Sample is first placed in Zn 2+ethanolic solution in 1min, then use alcohol flushing; Be placed in again S 2-methanol solution in 1min, with alcohol flushing, be so a circulation.Circulate 5 times, can form on CdTe surface the ZnS of several molecular layers, can effectively prevent the photoetch of electrode.
The quantum dot sensitized TiO of test ZnS/CdTe 2nano thin-film photoproduction cathodic protection effect.With the quantum dot sensitized TiO of ZnS/CdTe 2nano thin-film is light anode, is placed in photoelectrolytic cell, and wherein electrolyte is 0.5mol/LNa 2sO 4+ 0.5mol/LHCOOH solution, with 0.2mol/L NaOH regulator solution, pH is 9.6.Corrosion electrolytic cell is three-electrode system, and work electrode is protected metal, is Pt electrode to electrode, and reference electrode is saturated calomel electrode (SCE), take 0.5mol/LNaCl as medium solution.Light anode is connected by wire with protected metal electrode, and photoelectrolytic cell is connected by salt bridge (containing the agar of 1.0mol/L KCl) with corrosion electrolytic cell.When illumination, using 150W high pressure Xe lamp as white light source, direct irradiation is laminated film surface in photoelectrolytic cell.
Fig. 2 is the quantum dot sensitized TiO of ZnS/CdTe making 2the SEM figure of nano thin-film.As can be seen from the figure, this composite membrane is more smooth, and the distribution of quantum dot is more even.Due to the sensitization of quantum dot, the tube wall of nanotube is thickeied to some extent.
Fig. 3 is the optogalvanic spectra of different nano thin-films.Can find out, when film is pure TiO 2when nanometer film, as shown in Fig. 3 curve (a), the absorption of light is mainly concentrated on to ultraviolet region, and be that 335nm place photoelectric current reaches maximum 5300nA left and right at wavelength.When after film surface deposition CdTe quantum dot, Fig. 3 curve (b) shows that its photoelectric current intensity significantly strengthens, and light abstraction width extends to 600nm left and right.Because CdTe (1.47eV) is the semiconductor of narrow band gap, to TiO 2carry out sensitization processing, can greatly expand light abstraction width, effectively improve the utilance to light.When after the coated ZnS shell in surface, can find out from Fig. 3 curve (c), photoelectric current intensity slightly declines, reason is the greater band gap of ZnS (3.66eV), response to light is poor, has hindered to a certain extent the absorption of light, but impact is little.Importantly composite membrane exists ZnS skin can improve the stability of quantum dot.
Fig. 4 be 403 stainless steels in 0.5mol/L NaCl solution respectively with pure TiO in photoelectrolytic cell 2film and through CdCl 2solution-treated and untreated compound film electrode are coupled rear electrode current potential curve over time.As the pure TiO under stainless steel and illumination 2when membrane electrode is coupled, 403 stainless current potentials, from be down to approximately-300mV of the about 50mV of corrosion potential, play certain photoproduction cathodic protection effect.From figure, curve b can find out, while composite membrane not being carried out to annealing in process, under illumination, quickly fall to-400mV of the electrode potential of light anode left and right, but along with the carrying out of illumination, stainless electrode potential is shuffled gradually, illustrates that photo-anode film surface quantum dot is now very unstable, occurs to decompose to cause current potential just becoming.When cutting off after light source 2h, again carry out illumination, now stainless electrode potential and pure TiO 2when film is coupled, approach, illustrate that composite membrane is after 2h illumination, decompose substantially completely, even if be coated ZnS shell, still can not reduce the decomposition of quantum dot.When composite membrane is carried out after annealing in process, can find out from curve c, under illumination, quickly fall to-400mV of the stainless steel electrode current potential left and right being coupled, because ZnS itself exists certain defect, just start in a few minutes, current potential is shuffled to some extent, but along with the carrying out of illumination, be stabilized in gradually-380mV of current potential left and right, annealing in process is described, can effectively improves the stability of quantum dot.When cutting off after light source 2h, again carry out illumination, current potential is now also basicly stable in-380mV left and right, and the TiO of ZnS/CdTe after quantum dot sensitized is described 2nano composite membrane is stable, and can play good photoproduction cathodic protection effect to 403 stainless steels.
Embodiment 2
According to technique scheme (concrete steps), the quantum dot sensitized TiO of preparation ZnS/CdTe 2nano thin-film, and testing film as light anode to 403 stainless cathodic protection effects.
Take the thick rectangle pure titanium foil of 0.1mm as sample, its long 10mm, wide is 10mm.Specimen surface, after No. 400～No. 1500 silicon carbide paper polishings, is taken up in order of priority and is cleaned 8min at acetone, absolute ethyl alcohol and deionized water for ultrasonic ripple.
Take 4.5g ammonium fluoride, be dissolved in 333mL deionized water, add 500mL glycerol, mix.Under room temperature, do electrode with platinum, in above-mentioned solution, anodic oxidation 30min under 20V voltage.Then sample is placed on and in Muffle furnace, at 450 ℃, calcines 2h and cool to room temperature with the furnace.
Adopt constant pressure impulse electrodeposition process, use Autolab PGSTAT30 electrochemical workstation, first at above-mentioned TiO 2film of Nano tube array surface deposition CdTe quantum dot, 5mmol/L Na 2teO 3solution, 0.02mol/L CdSO 4and 0.05mol/LNa 3nTA (nitrilotriacetic acid trisodium) mixes as reaction solution, with 0.1mol/L sulfuric acid regulation solution pH be 8.3.Wherein Na 2teO 3preparation method as follows: by 0.399g TeO 2powder and 0.2g NaOH join in 500mL deionized water, and the 4h that refluxes at 70 ℃, is cooled to room temperature.Burst length is 0.2s, and pulse turn-off time is 1.5s, and pulse electromotive force is-1.3 V, and the circulation number of turns is 60.
In order effectively to reduce the surface defect density of quantum dot, by the film of Nano tube array preparing at 0.5mol/L CdCl 2in solution, soak 2min, in the baking oven of 80 ℃, dry 3min, then at 380 ℃ annealing in process 25min.So just make the TiO of CdTe sensitization 2composite membrane.
In order to improve the stability that obtained above-mentioned work done in the manner of a certain author is the composite membrane of light anode, adopt circulatory maceration at CdTe/TiO 2electrode surface deposition ZnS.Sample is first placed in 0.6mol/L Zn (NO 3) 2ethanolic solution in 1min, then use alcohol flushing; Be placed in again 0.1mol/L Na 21min in the methanol solution of S, with alcohol flushing, is so a circulation.Circulate 5 times, can form on CdTe surface the ZnS of several molecular layers, can effectively prevent the photoetch of composite membrane.Finally make the quantum dot sensitized TiO of ZnS/CdTe 2nano thin-film.
The quantum dot sensitized TiO of test ZnS/CdTe 2nano thin-film photoproduction cathodic protection effect.With the quantum dot sensitized TiO of ZnS/CdTe 2nano thin-film is light anode, is placed in photoelectrolytic cell, and wherein electrolyte is 0.5mol/L Na 2sO 4+ 0.5mol/LHCOOH solution, with 0.2mol/L NaOH regulator solution, pH is 9.6.Corrosion electrolytic cell is three-electrode system, and work electrode is protected metal, is Pt electrode to electrode, and reference electrode is saturated calomel electrode (SCE), take 0.5mol/L NaCl as medium solution.Light anode is connected by wire with protected metal electrode, and photoelectrolytic cell is connected by salt bridge (containing the agar of 1.0M KCl) with corrosion electrolytic cell.When illumination, using 150W high pressure Xe lamp as white light source, direct irradiation is laminated film surface in photoelectrolytic cell.
Fig. 5 is the SEM figure of the quantum dot sensitized TiO2 nano thin-film of ZnS/CdTe that makes.As can be seen from the figure, nanotube is more even, has the quantum dot of more amount to be distributed on tube wall and the mouth of pipe.
Fig. 6 is the optogalvanic spectra of different nano thin-films.Can find out from Fig. 6 curve (a), for pure TiO 2nano thin-film, is that 335nm place photoelectric current maximum reaches 5000nA left and right at wavelength, and the response of light is mainly concentrated on to ultra-violet (UV) band, and visible ray is not responded substantially.When after film surface deposition CdTe quantum dot, Fig. 6 curve (b) shows that its photoelectric current intensity significantly strengthens, and light abstraction width also extends to 600nm left and right.Due to prepared quantum dot fewer (as shown in Figure 5), the absorptive amplitude of visible ray is not had to strong in embodiment 1.When after the coated ZnS shell in surface, can find out from Fig. 6 curve (c), photoelectric current intensity declines to some extent, and reason is also that the ZnS semiconductor of broad-band gap is poor to the response of light, has hindered to a certain extent the absorption of light.
Fig. 7 be 403 stainless steels in 0.5mol/L NaCl solution respectively with pure TiO in photoelectrolytic cell 2film and compound film electrode are coupled rear electrode current potential curve over time, have contrasted CdCl 2the impact of solution-treated on composite membrane stability.As the pure TiO under stainless steel and illumination 2when membrane electrode is coupled, can find out from Fig. 7 curve (a), its electrode potential, from be down to approximately-335mV of corrosion potential, plays certain photoproduction cathodic protection effect.For the composite membrane without annealing in process, can find out from Fig. 7 curve (b), under illumination, quickly fall to-390mV of the electrode potential of light anode left and right, but along with the carrying out of illumination, the electrode potential of light anode is shuffled gradually, illustrates that quantum dot is now very unstable, occurs to decompose to cause current potential just becoming.When cutting off after light source 2h, again carry out illumination, now the electrode potential of composite membrane, in-280mV left and right, illustrate that composite membrane is after 2h illumination, substantially completely decomposition.When composite membrane is carried out after annealing in process, can find out from Fig. 7 curve (c), under illumination, quickly fall to-400mV of the current potential of light anode left and right, due to the defect of ZnS existence itself, just start in a few minutes, current potential is shuffled to some extent, but along with the carrying out of illumination, be stabilized in gradually-380mV of current potential left and right, annealing in process is described, can effectively improves the stability of quantum dot.When cutting off after light source 2h, again carry out illumination, current potential is now also basicly stable in-380mV left and right, can play good photoproduction cathodic protection effect to 403 stainless steels.
Basic principle of the present invention: TiO 2compound with the quantum spot semiconductor CdTe of narrow band gap, under irradiation, the valence band Electron absorption photon excitation of CdTe transits to conduction band, produces light induced electron-hole pair, and light induced electron transits to TiO from the conduction band of CdTe 2conduction band; the most backward metal surface migration being attached thereto; produce photogenerated current; cause metal surface electron density to increase; macro manifestations is that metal surface current potential reduces; and the spontaneous potential original far below metal, now metal can be cathode protecting state in thermodynamics stable state, metal is protected and avoids corroding.Meanwhile, hole is from TiO 2transfer to the hole of CdTe, effectively realized separating of electronics and hole.The TiO having reported at present 2film photoproduction cathodic protection effect is also poor, develops the technology of preparing of advanced metal-surface nano film, obtains good nanometer film and can improve its photoproduction cathodic protection effect to metal.

Claims (7)

  1. The quantum dot sensitized TiO of 1.ZnS/CdTe 2the preparation method of nano thin-film, is characterized in that comprising the following steps:
    1) prepare titanium matrix sample;
    2) prepare TiO at titanium matrix specimen surface 2film of Nano tube array, the described titanium surface TiO of preparing 2nanotube adopts anode oxidation method, and concrete grammar is as follows: by NH 4f is dissolved in deionized water, adds glycerol, obtains mixed solution, using platinum as to electrode, and at mixed solution Anodic Oxidation, then by sample calcining, then cool to room temperature with the furnace, make TiO2 film of Nano tube array at titanium matrix specimen surface; Described NH 4the proportioning of F, deionized water and glycerol is (4.5～5) g NH 4f: (300～400) mL deionized water: (500～600) mL glycerol, wherein NH 4f calculates in mass, and deionized water and glycerol are calculated by volume;
    3) prepare the quantum dot sensitized TiO of CdTe 2nano thin-film: the quantum dot sensitized TiO of described preparation ZnS/CdTe 2nano thin-film adopts constant pressure impulse electrodeposition process, and concrete grammar is as follows: in step 2) TiO that obtains 2film of Nano tube array surface deposition CdTe quantum dot, by Na 2teO 3solution, CdSO 4with nitrilotriacetic acid trisodium (Na 3nTA) mix after as reaction solution, use H 2sO 4regulating the pH of reaction solution is 8～9, adopts three-electrode system, with TiO 2film of Nano tube array is work electrode, and Pt is to electrode, and saturated calomel electrode is reference electrode, carries out constant pressure impulse electro-deposition on chem workstation, makes the quantum dot sensitized TiO of CdTe 2nano thin-film; Described Na 2teO 3the concentration of solution is (2～8) mmol/L, described CdSO 4concentration be (0.01～0.05) mol/L; The concentration of described nitrilotriacetic acid trisodium is (0.02～0.08) mol/L; Described H 2sO 4concentration be (0.05～0.20) mol/L; Described pulse parameter of carrying out constant pressure impulse electro-deposition on chem workstation is: the burst length is (0.05～0.20) s, pulse-off interval time is (0.5～1.5) s, pulse electromotive force is (1.3～-1.5) V, and the circulation number of turns is (40～100);
    4) prepare the quantum dot sensitized TiO of ZnS/CdTe 2nano thin-film: by step 3) the quantum dot sensitized TiO of CdTe that makes 2nano thin-film is first at CdCl 2in solution, soak, dry after annealing processing, make CdTe/TiO 2composite membrane; Adopt again circulatory maceration at CdTe/TiO 2composite membrane surface deposition ZnS, concrete grammar is as follows: by the CdTe/TiO that contains of preparation 2the sample of composite membrane is first soaked in Zn 2+ethanolic solution in (1～2) min, then use alcohol flushing; Be placed in again S 2-methanol solution in soak (1～2) min, use again alcohol flushing, obtain the quantum dot sensitized TiO of ZnS/CdTe 2nano thin-film; Described CdCl 2concentration be (0.2～0.8) mol/L, the time of described immersion is 0.5～5min.
  2. 2. the quantum dot sensitized TiO of ZnS/CdTe as claimed in claim 1 2the preparation method of nano thin-film, is characterized in that in step 1) in, the described concrete grammar of preparing titanium matrix sample is: using titanium foil as titanium matrix, by after the polishing of titanium matrix surface, clean, obtain titanium matrix sample.
  3. 3. the quantum dot sensitized TiO of ZnS/CdTe as claimed in claim 2 2the preparation method of nano thin-film, is characterized in that described titanium matrix is rectangle titanium matrix, and length is (1.0～1.5) cm, and wide is (1.0～1.5) cm, and thickness is (0.05～0.15) mm; The Ti content of described titanium foil is more than 99.9%; Described polishing adopts 400～No. 1500 silicon carbide paper polishings, and described cleaning is to clean (5～10) min at acetone, absolute ethyl alcohol and deionized water for ultrasonic ripple successively.
  4. 4. the quantum dot sensitized TiO of ZnS/CdTe as claimed in claim 1 2the preparation method of nano thin-film, is characterized in that in step 2) in, described anodised voltage is (20～30) V, the anodised time is (20～30) min; The condition of described calcining is for being placed on sample in Muffle furnace calcining (1.5～2.0) h at (450～550) ℃.
  5. 5. the quantum dot sensitized TiO of ZnS/CdTe as claimed in claim 1 2the preparation method of nano thin-film, is characterized in that in step 3) in, described Na 2teO 3preparation method be: by (0.350～0.450) g TeO 2powder and (0.100～0.300) g NaOH join in (400～600) mL deionized water, and (2～5) h that refluxes at 70 ℃, is cooled to room temperature, obtains Na 2teO 3.
  6. 6. the quantum dot sensitized TiO of ZnS/CdTe as claimed in claim 1 2the preparation method of nano thin-film, is characterized in that in step 4) in, the condition of described oven dry is in the baking oven of (60～80) ℃, to dry (3～8) min; The condition of described annealing in process is annealing in process (25～35) min at (350～450) ℃.
  7. 7. the quantum dot sensitized TiO of ZnS/CdTe as claimed in claim 1 2the preparation method of nano thin-film, is characterized in that in step 4) in, described employing circulatory maceration is at CdTe/TiO 2composite membrane surface deposition ZnS circulation (3～5) is inferior.
CN201210032484.9A 2012-02-14 2012-02-14 Preparation method of zinc sulfide (ZnS)/cadmium telluride (CdTe) quantum dot sensitization titanium dioxide (TiO2) nano film Expired - Fee Related CN102543457B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201210032484.9A CN102543457B (en) 2012-02-14 2012-02-14 Preparation method of zinc sulfide (ZnS)/cadmium telluride (CdTe) quantum dot sensitization titanium dioxide (TiO2) nano film

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201210032484.9A CN102543457B (en) 2012-02-14 2012-02-14 Preparation method of zinc sulfide (ZnS)/cadmium telluride (CdTe) quantum dot sensitization titanium dioxide (TiO2) nano film

Publications (2)

Publication Number Publication Date
CN102543457A CN102543457A (en) 2012-07-04
CN102543457B true CN102543457B (en) 2014-06-11

Family

ID=46350101

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201210032484.9A Expired - Fee Related CN102543457B (en) 2012-02-14 2012-02-14 Preparation method of zinc sulfide (ZnS)/cadmium telluride (CdTe) quantum dot sensitization titanium dioxide (TiO2) nano film

Country Status (1)

Country Link
CN (1) CN102543457B (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102903538B (en) * 2012-10-17 2015-10-28 西安交通大学 The electrochemical method of the quantum dot sensitized wide bandgap semiconductor electrode of a kind of controlled synthesis
CN102965645A (en) * 2012-11-13 2013-03-13 同济大学 Preparation method of CdTe/ZnS-nanocrystal-comodified TiO2 nanotube array
CN103952708B (en) * 2014-04-10 2016-03-23 中国科学院海洋研究所 For the Ag/SnO of photoproduction galvanic protection 2/ TiO 2the preparation method of composite film photo-anode
CN107993923B (en) * 2017-12-08 2020-02-21 青岛大学 Preparation method of controllable quantum dot array based on photothermal effect
CN108314085B (en) * 2018-02-06 2019-11-01 厦门大学 The preparation method of tungstic trioxide nano-slice complex light anode

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101956222A (en) * 2010-10-27 2011-01-26 厦门大学 Preparation method of titanium dioxide nanotube array sensitized by cadmium sulfide nanoparticles

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101956222A (en) * 2010-10-27 2011-01-26 厦门大学 Preparation method of titanium dioxide nanotube array sensitized by cadmium sulfide nanoparticles

Non-Patent Citations (6)

* Cited by examiner, † Cited by third party
Title
Aligned ZnO/CdTe Core Shell Nanocable Arrays on Indium Tin Oxide: Synthesis and Photoelectrochemical Properties;xian wang等;《ACS NANO》;20100506;第4卷(第6期);3307页左栏全部 *
Jason A. Seabold等.Photoelectrochemical Properties of Heterojunction CdTe/TiO2 Electrodes Constructed Using Highly Ordered TiO2 Nanotube Arrays.《Chem. Mater. 2008》.2008,
Photoelectrochemical Properties of Heterojunction CdTe/TiO2 Electrodes Constructed Using Highly Ordered TiO2 Nanotube Arrays;Jason A. Seabold等;《Chem. Mater. 2008》;20080729;5267页右栏第2-5段 *
xian wang等.Aligned ZnO/CdTe Core Shell Nanocable Arrays on Indium Tin Oxide: Synthesis and Photoelectrochemical Properties.《ACS NANO》.2010,第4卷(第6期),
Ze-Quan Lin等.A highly efficient ZnS/CdS@TiO2 photoelectrode for photogenerated cathodic protection of metals.《 Electrochimica Acta》.2010,
Ze-Quan Lin等.A highly efficient ZnS/CdSTiO2 photoelectrode for photogenerated cathodic protection of metals.《 Electrochimica Acta》.2010, *

Also Published As

Publication number Publication date
CN102543457A (en) 2012-07-04

Similar Documents

Publication Publication Date Title
CN103205760B (en) For the Ag of photoproduction galvanic protection 2s/TiO 2the preparation method of composite film photo-anode
Zeng et al. A low-cost photoelectrochemical tandem cell for highly-stable and efficient solar water splitting
CN106555188B (en) Ag/ graphene/titania nanotube composite film photo-anode preparation method for photoproduction cathodic protection
CN106894024B (en) Accumulation energy type tungstic acid/strontium titanates/nano titania composite film photo-anode preparation method
CN107723712B (en) ZnIn for photoproduction cathodic protection2S4/TiO2Preparation method of nanotube composite film photo-anode
CN103952708B (en) For the Ag/SnO of photoproduction galvanic protection 2/ TiO 2the preparation method of composite film photo-anode
CN101608316B (en) Device for producing hydrogen through decomposing water
CN108823573B (en) Hydrothermal method for preparing Ni 3 S 2 /TiO 2 Method for preparing nano tube composite film photo-anode
CN102543457B (en) Preparation method of zinc sulfide (ZnS)/cadmium telluride (CdTe) quantum dot sensitization titanium dioxide (TiO2) nano film
CN102352494A (en) Preparation method of CdSe/CdS quantum dot sensitized TiO2 nanometer tube composite film
CN107557789B (en) A kind of optical anode material and its preparation and application
CN103361689A (en) Method for preparing titanium dioxide nanotube array photoelectrode
CN106498408B (en) A kind of preparation of the nano composite membrane light anode for photoproduction cathodic protection
CN104357852B (en) MnSe/TiO2 composite film for photogenerated cathode protection as well as preparation and application thereof
JP2003238104A (en) Apparatus for generating hydrogen by light
CN107699901A (en) Preparation method for zinc-iron aluminum hydrotalcite/titanium dioxide composite film light anode of photoproduction cathodic protection
CN103354283A (en) Gold nanoparticle-modified dendritic titanium dioxide nanorod array electrode, as well as preparation method and application of hydrogen production by photocatalytic water splitting
CN102874747B (en) Method for preparing multilevel structural material by performing epitaxial growth of layered double hydroxide (LDH) based on guiding of electric field of metallic oxide nano array
CN102360958B (en) Preparation method of photo-anode of ZnS/Au/TiO2 nano composite film
CN103474517A (en) Preparation method of SrTiO3 nano composite film photoanode
CN104264158A (en) Preparation method of graphene/CdTe-TiO2 composite membrane photo-anode
CN105386061A (en) Method for preparing Bi2S3/TiO2 nanorod composite-film photo-anodes
CN111424301B (en) Pulse potential mode for improving CuO photoelectrocatalysis CO2Method for conversion efficiency
CN104164693A (en) A preparing method of a graphene sensitized CdSe/TiO2 nanotube composite membrane
CN110042452B (en) Photo-anode composite film, preparation method and application thereof

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20140611

Termination date: 20210214

CF01 Termination of patent right due to non-payment of annual fee