CN102626625A - Precious metal-doped ZnO nanoscale particles and use of the precious metal-doped ZnO nanoscale particles as photocatalyst for unsymmetrical dimethylhydrazine wastewater degradation - Google Patents
Precious metal-doped ZnO nanoscale particles and use of the precious metal-doped ZnO nanoscale particles as photocatalyst for unsymmetrical dimethylhydrazine wastewater degradation Download PDFInfo
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Abstract
The invention relates to precious metal-doped ZnO nanoscale particles and a use thereof. The precious metal-doped ZnO nanoscale particles are ZnO/Ag and ZnO/Pd nanoscale particles which are prepared from zinc acetate, sodium hydroxide, silver nitrate and palladium chloride by an ethanol auxiliary hydrothermal method, wherein the diffraction peak of ZnO belongs to a hexagonal wurtzite structure; a space crystal group of ZnO belongs to P63mc(186); a point lattice constant a of ZnO is equal to a point lattice constant b of ZnO and is equal to 0.3249nm; a point lattice constant c of ZnO is equal to 0.5205nm; the diffraction peak of Ag is in accordance with a standard map JCPDF:87-0717; a space crystal group of Ag belongs to Fm-3m(225); a point lattice constant a of Ag is equal to a point lattice constant b of Ag, is equal to a point lattice constant c of Ag and is equal to 4.086nm; the diffraction peak of Pd is in accordance with a standard map JCPDF:88-2335; a space crystal group of Pd belongs to Fm-3m(225); and a point lattice constant a of Pd is equal to a point lattice constant b of Pd, is equal to a point lattice constant c of Pd and is equal to 3.900nm. The use of the precious metal-doped ZnO nanoscale particles comprises that the precious metal-doped ZnO nanoscale particles are utilized as a photocatalyst for unsymmetrical dimethylhydrazine wastewater degradation. Compared with the prior art, the precious metal-doped ZnO nanoscale particles have good morphology and a high degree of crystallization; a preparation method of the precious metal-doped ZnO nanoscale particles is simple and has good repeatability; a result of a test shows that the precious metal-doped ZnO nanoscale particles can be degraded faster and more thoroughly under sunlight; and the precious metal-doped ZnO nanoscale particles have a lower production cost, better energy-saving effects and a certain referential meaning for industrial application.
Description
Technical field
The invention belongs to technical field of waste water processing, relate to a kind of precious metal doping ZnO nano particle material and purposes, relate in particular to this material is used for the photocatalytic degradation under the solar light irradiation of uns-dimethylhydrazine waste water as photochemical catalyst.
Background technology
Nano-ZnO is nano material and semi-conductive complex, has excellent photocatalytic performance.But the spectral response range of ZnO is narrower, can only utilize in the sunshine 5% ultraviolet light.Utilize noble metal decorated semiconductor light-catalyst not only can expand the spectral response range of ZnO, and can effectively catch excitation electron, improve its photocatalytic activity.Noble metal is at the nano level cluster of the general formation of semiconductor surface deposition; The noble metal of deposition contacts with semiconductor; Help the carrier redistribution; Electronics is transferred to the lower metal of fermi level from the higher semiconductor of fermi level, and is identical up to both fermi levels, forms Schottky energy barrier (Schottky Barrier).The Schottky energy barrier is effective trap of capturing light induced electron, photo-generated carrier is separated, thereby effectively suppressed the compound of hole and electronics, has improved the catalytic activity of photochemical catalyst.Uns-dimethylhydrazine waste water is the difficult problem that the aerospace industry sewage pollution is administered always; Especially the uns-dimethylhydrazine waste water of low concentration (100mg/L below) deal with waste time and energy and processing speed slow; Be not easy thorough mineralising and become the inorganic molecules material, general traditional treatment method is inapplicable.Utilize the conductor photocatalysis degradable organic pollutant to obtain good effect and begin progressively to apply in recent years, therefore utilizing precious metal doping nano-ZnO photocatalytic degradation uns-dimethylhydrazine waste water is one of focus of current photocatalysis field.
In the prior art before the present invention; " research of neodymium-doped nano zine oxide catalytic degradation uns-dimethylhydrazine " and Xu Wenguo, Jia Yan, the Sha Jing that are published in " Beijing Institute of Technology's journal " 2009 29 3 phases of volume by people such as the Zhou Yinbai of units such as college of science of Beijing Institute of Technology, Xu Wenguo, Zhang Guangyou divide the people to be published in " Beijing Institute of Technology's journal " to roll up in 2010 30 in " copper neodymium co-doped nano TiO2 photocatalytic degradation uns-dimethylhydrazine waste water " article of 8 phases; The Processing Technology Research report of rare earth metal dopen Nano ZnO photocatalytic degradation uns-dimethylhydrazine waste water is disclosed; Be the effective way of photocatalytic degradation uns-dimethylhydrazine waste water, but in the technology that is disclosed, the technology of preparing of ZnO is complicated; The consumption that degraded uns-dimethylhydrazine waste water gets the rare earth photochemical catalyst is big; Cost is high, simultaneously must be with ultraviolet light as the photocatalysis light source, and power consumption is big.
Summary of the invention
To above-mentioned prior art situation; The objective of the invention is to; Provide a kind of and adopt that semiconductor is compound, precious metal doping modifies ZnO/Ag, the ZnO/Pd nano particle that improves quantum yield, expands spectral absorption different-shape scope, that the ethanol assisting alcohol-hydrothermal method is prepared; And with this ZnO/Ag, ZnO/Pd nano particle as the sunlight catalytic agent, method is simple, the method for the degraded uns-dimethylhydrazine waste water that cost is low, power consumption is few.
Existing the present invention's technology solution party is pressed narrated as follows:
The ZnO/Ag of a kind of precious metal doping of the present invention, ZnO/Pd nano particle is characterized in that: described ZnO/Ag, ZnO/Pd nano particle are raw material with zinc acetate, NaOH, silver nitrate and palladium bichloride, prepare with the ethanol assisting alcohol-hydrothermal method.
The present invention further provides a kind of ZnO nano particle of precious metal doping; It is characterized in that: described precious metal doping ZnO nano particle is the ZnO/Ag nano particle with the preparation of ethanol assisting alcohol-hydrothermal method; The concentration that its raw material acetic acid zinc concentration is 0.1～0.3mol/L, silver nitrate is that 0.05～0.1mmol/L, concentration sodium hydroxide are 1.0～1.5mol/L; The volume ratio of ethanol/water is 20～40: 5～15, and reaction temperature is 150～200 ℃, and the reaction time is 10h～24h; 50 ℃～70 ℃ of baking temperatures, be 6～10 hours drying time.
The present invention further provides a kind of ZnO nano particle of precious metal doping; It is characterized in that: described precious metal doping ZnO nano particle is the ZnO/Pd nano particle with the preparation of ethanol assisting alcohol-hydrothermal method, and its raw material raw material acetic acid zinc concentration is 0.1～0.3mol/L, PdCl
2Solution for adopt that the ammoniacal liquor complexometry processes concentration be the pale yellow solution of 0.01mol/L; Concentration sodium hydroxide is 1.0～1.5mol/L; The volume ratio of ethanol/water is 20～40: 5～15, and reaction temperature is 150～200 ℃, and the reaction time is 10h～24h; 50 ℃～70 ℃ of baking temperatures, be 6～10 hours drying time.
The present invention further provides a kind of ZnO nano particle of precious metal doping, it is characterized in that: described ZnO/Ag nano particle is yellowish-brown; Described ZnO/Pd nano particle gray.
The present invention further provides a kind of ZnO nano particle of precious metal doping, it is characterized in that: the mol ratio of described precious metals ag, Pd and ZnO is 0.5～2: 100.
The present invention further provides a kind of ZnO nano particle of precious metal doping, it is characterized in that: described ZnO/Ag, ZnO/Pd nano particle, its precious metal ion are finally modified ZnO with the form of simple substance, and crystallite dimension is between 41～46nm; Absorption spectrum ranges is in the visible region of 400～800nm;
The present invention further provides a kind of ZnO nano particle of precious metal doping; It is characterized in that: described ZnO/Ag nano particle, the diffraction maximum of its ZnO belongs to hexagonal wurtzite structure, and the space crystal group belongs to P63mc (186); Point lattice constant a=b=0.3249nm, c=0.5205nm; The diffraction maximum of its Ag and standard diagram JCPDF:87-0717 coincide, and the space crystal group belongs to Fm-3m (225), point lattice constant a=b=c=4.086nm.
The present invention further provides a kind of ZnO nano particle of precious metal doping; It is characterized in that: described ZnO/Pd nano particle, the diffraction maximum of its ZnO belongs to hexagonal wurtzite structure, and the space crystal group belongs to P63mc (186); Point lattice constant a=b=0.3249nm, c=0.5205nm; The diffraction maximum of its Pd and standard diagram JCPDF:88-2335 coincide, and the space crystal group belongs to Fm-3m (225), point lattice constant a=b=c=3.900nm.
Precious metal doping ZnO nano particle of the present invention is used for the degraded of uns-dimethylhydrazine waste water; It is characterized in that: the ZnO/Ag or the ZnO/Pd nano particle of preparation are joined in the low concentration uns-dimethylhydrazine waste water; The ZnO/Ag that adds or the concentration of ZnO/Pd nano particle are 100～300mg/L; Stirring makes ZnO/Ag or ZnO/Pd nanoparticulate dispersed even, places catalytic degradation low concentration uns-dimethylhydrazine waste water under the outdoor sunshine, and irradiation time is 0.5～4 hour; Under the ultraviolet light ZnO/Ag and ZnO/Pd to uns-dimethylhydrazine waste water the most degradation rate be respectively 92.7% and 76.8%; All more than 80%, wherein when the mol ratio of Ag and Zn was 0.5: 100, degradation rate was 92.7% to the degradation rate of uns-dimethylhydrazine waste water for ZnO/Ag and ZnO/Pd under the sunshine; Degradation rate is than being 87.2.% when the mol ratio of Pd and Zn is 1: 100. The photocatalysis performance of ZnO/Pd under sunshine be than good under ultraviolet light, under the sunshine photocatalysis intermediate product be decomposed sooner, more thorough; Used ZnO/Ag or ZnO/Pd nano particle can be reused after centrifugalizing.
The superiority that the present invention compares with prior art is:
(1) utilize the ethanol assisting alcohol-hydrothermal method to prepare granular ZnO/Ag and ZnO/Pd, the pattern of product is good, and degree of crystallinity is high, and preparation technology is simple, and is repeatable strong, for ZnO utilizes sunshine to carry out photocatalytic degradation as excitation source important evidence is provided.
(2) utilize ZnO/Ag and ZnO/Pd photocatalytic degradation uns-dimethylhydrazine waste water under ultraviolet light and sunshine respectively, the degradation rate of result of the test proof under sunshine is faster, and degrades more thoroughly.For utilizing applying of nano-ZnO photocatalytic degradation uns-dimethylhydrazine waste water to have significant values.
(3) noble metal decorated ZnO helps the expansion of its spectral response range; Utilize sunshine uns-dimethylhydrazine waste water to be carried out photocatalytic degradation as excitation source; All having very strong advantage aspect production cost and energy-conservation two, industrial applications had certain significance for reference.
Description of drawings
Fig. 1: ZnO/Ag nano particle X-ray energy spectrum (EDS) figure (sample a2, b2)
Fig. 2: the x ray diffraction of ZnO/Ag nano particle (XRD) figure (sample a1～a3)
Fig. 3: the x ray diffraction of ZnO/Pd nano particle (XRD) figure (sample b1～b3)
Fig. 4: ultraviolet-visible diffuse reflection spectrum (UV-vis) figure of ZnO/Ag nano particle (sample a1～a3)
Fig. 5: ultraviolet-visible diffuse reflection spectrum (UV-vis) figure of ZnO/Pd nano particle (sample b1～b3)
Fig. 6: ZnO/Ag under ultraviolet light to the photocatalytic degradation design sketch of uns-dimethylhydrazine waste water (sample a1～a3)
Fig. 7: ZnO/Pd under ultraviolet light to the photocatalytic degradation design sketch of uns-dimethylhydrazine waste water (sample b1～b3)
Fig. 8: ZnO/Ag under sunshine to the photocatalytic degradation design sketch of uns-dimethylhydrazine waste water (sample a1～a3)
Fig. 9: ZnO/Pd under sunshine to the photocatalytic degradation design sketch of uns-dimethylhydrazine waste water (sample b1～b3)
Annex: ZnO/Ag nano particle ESEM (SEM) photo figure (sample a1～a3, b1～b3)
The specific embodiment
Do below in conjunction with the accompanying drawing specific embodiments of the invention and to further describe.
Embodiment 1: the preparation of precious metal doping ZnO nano particle ZnO/Ag
1, accurately takes by weighing the AgNO of 0.2mmol
3Pack in the volumetric flask of 20mL, to scale, promptly obtain the AgNO of 0.01mol/L with distilled water diluting
3Solution.
2, in three Teflon lining courages, respectively add the 30mL absolute ethyl alcohol, add respectively again: AgNO a.2.5mL0.01mol/L
3Solution and 7.5mL distilled water; B.5mL0.01mol/L AgNO
3Solution and 5mL distilled water; C.10mL0.01mol/L AgNO
3Solution.Take by weighing the Zn (Ac) of 0.005mol
22H
2O adds in each lining courage, makes Zn in the solution
2+And Ag
+Mol ratio be respectively 100: 0.5,100: 1,100: 2.To serve as a contrast courage places on the magnetic stirring apparatus and to stir 10min and make Zn (Ac)
22H
2O dissolves fully, adds 0.05molNaOH more respectively, continues to stir 10min.
3, Teflon is served as a contrast courage and be sealed in the autoclave, place thermostatic drying chamber, 160 ℃ are reacted 12h down.
4, after the question response still is cooled to room temperature, with the gained white precipitate with distilled water and absolute ethyl alcohol washed several times with water.At last centrifugal back gained sample is placed drying box, dry 8h under 60 ℃ obtains the ZnO/Ag sample, and end product is designated as a1, a2, a3 respectively.
Embodiment 2: the preparation of precious metal doping ZnO nano particle ZnO/Pd
Because PdCl
2Water insoluble, experiment is in order to prepare the PdCl of 0.01mol/L
2Solution adopts the ammoniacal liquor complexometry, makes PdCl
2Form Pd (NH) with ammoniacal liquor
2Cl
2Complex compound forms pale yellow solution in the water-bath environment.
1, takes by weighing the PbCl of 0.2mmol
2Add in the volumetric flask of 20mL, add 0.3mL ammoniacal liquor, with distilled water diluting to scale.Be placed on 10min to PdCl in 70 ℃ the water-bath
2Dissolve, obtain the PdCl of 0.01mol/L
2Solution.
2,3,4 steps are identical with the preparation process of ZnO/Ag, and end product is designated as b1, b2, b3.
Different with the photocatalysis experiment of front, consider that ZnO/Ag and ZnO/Pd also have stronger absorption in the visible region, use ultra violet lamp and solar light irradiation to study their photocatalysis performance respectively.
Referring to annex: be the sem photograph of sample, wherein: a1～a3 is the ZnO/Ag nano particle sample that the present invention prepares; B1～b3 is the ZnO/Pd nano particle sample that the present invention prepares; Can find out that from the sem photograph of sample all samples are not too big difference on pattern, all is graininess; In sample segment, have the bigger particle; The diameter of most of nano particle all between 50～200nm, dispersed fine, significantly do not reunite by appearance.The rear-earth-doped sample of before preparation is compared, and noble metal decorated ZnO nano particle diameter seems littler on macroscopic view, explain that noble metal can suppress the reunion of nanocrystal to a certain extent.
Referring to Fig. 1: be the X-ray energy spectrum figure of sample a2 and b2, as can be seen from the figure, only contain Zn, O, three kinds of elements of Ag among the sample a2, sample b2 only contains Zn, O, three kinds of elements of Pd, except the element of modifying usefulness, does not have other impurity, and purity is higher.
Referring to Fig. 2,3: the X ray diffracting spectrum that is respectively sample ZnO/Ag and ZnO/Pd.All XRD figure spectrum all demonstrates ZnO/Ag and only contains ZnO and Ag among Fig. 3; The all ZnO in the diffraction maximum of ZnO and front is the same; Coincide with standard diagram (JCPDF:89-0510); Belong to hexagonal wurtzite structure (the space crystal group belongs to P63mc (186)), point lattice constant a=b=0.3249nm, c=0.5205nm; The diffraction maximum of Ag and standard diagram (JCPDF:87-0717) coincide, and the space crystal group belongs to Fm-3m (225), point lattice constant a=b=c=4.086nm.Along with the increase of mixing the Ag amount, its characteristic peak is more and more, and intensity is also more and more stronger.All diffraction maximums are all very sharp-pointed, and the sample degree of crystallinity that surface preparation goes out is high, and crystal development is better.The crystallite dimension that is calculated a1, a2, a3 by the Debye-Scherrer formula is respectively 45.31nm, 45.71nm, 45.96nm..
The peak that also has only two kinds of materials in the XRD figure spectrum among Fig. 3: ZnO and Pd, wherein the diffraction maximum of ZnO and front is in full accord.The diffraction maximum of Pd and standard diagram (JCPDF:88-2335), space crystal group belong to Fm-3m (225), point lattice constant a=b=c=3.900nm.Not having Pd in the diffraction maximum of b1, possibly be because Pd content is too low or dispersion evenly and not detects very much.Along with the increase of mixing the Pd amount, the characteristic peak of Pd increases gradually, and intensity also increases gradually.The crystallite dimension that calculates b1, b2, b3 at last is respectively 44.23nm, 43.77nm, 41.57nm.
Referring to Fig. 4: the ultraviolet-visible diffuse reflection abosrption spectrogram that is ZnO/Ag; From figure, can see significantly; All nano ZnO materials of ZnO/Ag and front are compared, and maximum difference is that the wave band of the uv-visible absorption spectra of ZnO/Ag is significantly expanded; Also there is stronger absorption visible region at 400～800nm wave band, and this phenomenon shows that this material can carry out the photocatalysis experiment as excitation source with sunshine.A1, a2, the maximum absorption band of a3 in the visible region are respectively 468nm, 468nm, 472nm, increase along with the increase of mixing the Ag amount in the absorption intensity of visible light wave range, therefore can judge, ZnO/Ag is that Ag mixes and causes in the absorption of visible light wave range.In the ultra-violet (UV) band of 200～400nm wave band, compare pure ZnO, mix that obvious red shift appears in the ABSORPTION EDGE of ZnO behind the Ag, possibly be because the atomic radius of Ag is bigger than Zn, make the atomic distance of ZnO lattice become big, energy level spacing reduces to cause; Absorption intensity reduces along with the increase of mixing the Ag amount increases earlier then, and the maximum absorption band of a1, a2, a3 is respectively 336nm, 332nm, 340nm, and (358nm) compares with the graininess nano-ZnO, and obvious blue shift is arranged.
Referring to Fig. 5: the ultraviolet-visible diffuse reflection abosrption spectrogram that is ZnO/Pd; Similar with ZnO/Ag; ZnO/Pd compares with the ZnO material of front, and maximum difference is that the wave band of absorption spectrum is significantly expanded in the visible region, at the wave band of 400～900nm; Along with the increase of wavelength, absorption intensity is increasing.In the ultra-violet (UV) band of 200～400nm, except the ABSORPTION EDGE blue shift of b1, red shift all takes place in the ABSORPTION EDGE of b2 and b3, possibly be that mixing of Pd causes that the defect level of ZnO causes.The maximum absorption wavelength of b1, b2, b3 is respectively 330nm, 336nm, 344nm, has compared obvious blue shift with pure ZnO.
ZnO/Ag and ZnO/Pd have very strong absorption in the visible region, what it may be noted that a bit is that the ZnO/Ag of this Experiment Preparation is yellowish-brown; The ZnO/Pd gray; Along with the increase of Ag and Pd doping, color is deepened gradually, infers that they are relevant with self color in the absorption of visible region.Absorption spectrum comes down to the red shift of absorption spectrum to the expansion of visible region, and strong crystal face electronics coupled is the basic factor that causes the absorption bands red shift between Ag and the ZnO.Absorption in the visible region belongs to surface plasma and absorbs; Mixing of noble metal; Make electronics transfer to the low noble metal of fermi level (Ag, Pd) from the high semiconductor of fermi level (ZnO); The electronics of semiconductor surface lacks makes the red shift of surface plasma absorption bands, and along with the increase of mixing the Ag amount, absorption intensity is increasing.The ultraviolet-visible of ZnO/Pd absorbs with ZnO/Ag similar, also causes because of the crystal face electronics coupled.
Referring to Fig. 6: be ZnO/Ag photocatalytic degradation design sketch to uns-dimethylhydrazine waste water under ultraviolet light,, the catalytic performance of uns-dimethylhydrazine weakened gradually along with the increase of mixing the Ag amount.Through the photocatalytic degradation of 2h, a1, a2, a3 are respectively 92.7%, 89.3%, 82.7% to the degradation rate of uns-dimethylhydrazine, compare with pure ZnO, and the degradation rate of a1 has improved one times nearly.At incipient 20min, degradation rate is very fast, and a1, a3 are obvious fast more a lot of than a2, and the degradation rate of a2 and a3 are similar when the reaction time reaches 70min, and along with the continuation of reacting, the degradation rate of a2 approaches a1.Can find out that in the time period of 40～100min, the degradation rate of a2 is the fastest.Explain that catalytic efficiency is the highest when the mol ratio of Ag and Zn is 1: 100.Measure when too much when mixing Ag; Form the trap of a lot of light induced electrons, the distance between each trap is reduced, so the Schottky energy barrier is crossed and the probability that combines increases in electronics and hole; Excessive Ag has become the complex centre in electronics and hole, influences the photocatalytic activity of ZnO/Ag.
Referring to Fig. 7: be ZnO/Pd photocatalytic degradation design sketch to uns-dimethylhydrazine waste water under ultraviolet light, along with the increase of mixing the Pd amount, photocatalysis performance strengthens afterwards earlier and weakens.B1, b2, the b3 degradation rate to uns-dimethylhydrazine waste water behind 2h reaches 72.2%, 76.8%, 68.4% respectively, and the photocatalysis effect of b1 not as b3, surpassed b3 at initial 60min afterwards gradually.The optimum doping amount of Pd is that the mol ratio of Pd and Zn is 1: 100, when mixing the Pd quantity not sufficient, is unfavorable for the formation of Schottky energy barrier, captures the trap number deficiency of light induced electron among the ZnO, and electronics can not separate with the hole to greatest extent; When doping is too high, can make excessive Pd become the complex centre of electron-hole pair again, weaken the effect of trap.
Referring to Fig. 8: be ZnO/Ag photocatalytic degradation design sketch to uns-dimethylhydrazine waste water under sunshine, wherein c is the photocatalysis effect of graininess ZnO under sunshine, through 2h not degraded basically.As can be seen from the figure, ZnO/Ag degradation rate in initial 40min is the fastest, and along with continuing of reaction, degradation rate slows down rapidly, and light-catalyzed reaction reaches balance basically after 60min, and wherein the degradation rate of a2 when 60min can reach 75.7%.Through the solar light irradiation of 2h, a1, a2, a3 reach 76.5%, 80.2%, 79.2% respectively to the degradation rate of uns-dimethylhydrazine, and wherein the degradation effect of a3 under sunshine and under ultraviolet light is very approaching.The spectrum respective range that ZnO/Ag has been described is extended to visible light wave range, under irradiation of sunlight, can be excited to produce hole-duplet.When the mol ratio of Ag and Zn is that 1: 100 time catalytic effect is best; It is most effective that the light induced electron trap that form because of the Schottky energy barrier this moment is brought into play; Mix Ag and measured the low or too high generation that all is unfavorable for hole-electron pair and separated, reduce the photocatalysis performance of ZnO/Ag.
Referring to Fig. 9: be ZnO/Pd photocatalytic degradation design sketch to uns-dimethylhydrazine waste water under sunshine; Similar with ZnO/Ag; 40min degradation rate initial is the fastest, when 60min, reaches balance basically, and wherein b2 degradation rate to uns-dimethylhydrazine when 60min can reach 72.5%.Through the solar light irradiation of 2h, b1, b2, b3 reach 74.6%, 80.5%, 78.8% respectively to the degradation rate of uns-dimethylhydrazine, compare with the degradation effect under the ultraviolet light, all are significantly improved, and be consistent with the uv-visible absorption spectra of ZnO/Pd.This is all compound, that the doping ZnO material is maximum differences of ZnO/Pd and other, wherein b3 under sunshine to the degradation rate of uns-dimethylhydrazine than under ultraviolet light, having improved 10.4%.The optimum doping amount of Pd is identical with Ag, and it is too high or too much all be unfavorable for light-catalyzed reaction to mix Pd amount.
Claims (10)
1. the ZnO nano particle of a precious metal doping; It is characterized in that: the ZnO nano particle of described precious metal doping is meant ZnO/Ag, ZnO/Pd nano particle; With zinc acetate, NaOH, silver nitrate and palladium bichloride is raw material, prepares with the ethanol assisting alcohol-hydrothermal method.
2. the ZnO nano particle of a kind of precious metal doping according to claim 1; It is characterized in that: the raw material acetic acid zinc concentration of said ZnO/Ag nano particle is that the concentration of 0.1～0.3mol/L, silver nitrate is that 0.05～0.1mmol/L, concentration sodium hydroxide are 1.0～1.5mol/L; The volume ratio of ethanol/water is 20～40: 5～15, and reaction temperature is 150～200 ℃, and the reaction time is 10h～24h; 50 ℃～70 ℃ of baking temperatures, be 6～10 hours drying time.
3. the present invention further provides a kind of ZnO nano particle of precious metal doping, it is characterized in that: the raw material raw material acetic acid zinc concentration of described ZnO/Pd nano particle is 0.1～0.3mol/L, PdCl
2Solution for adopt that the ammoniacal liquor complexometry processes concentration be the pale yellow solution of 0.01mol/L; Concentration sodium hydroxide is 1.0～1.5mol/L; The volume ratio of ethanol/water is 20～40: 5～15, and reaction temperature is 150～200 ℃, and the reaction time is 10h～24h; 50 ℃～70 ℃ of baking temperatures, be 6～10 hours drying time.
4. the ZnO nano particle of a kind of precious metal doping according to claim 1, it is characterized in that: described ZnO/Ag nano particle is yellowish-brown; Described ZnO/Pd nano particle gray.
5. the ZnO nano particle of a kind of precious metal doping according to claim 1, it is characterized in that: the mol ratio of described precious metals ag, Pd and ZnO is 0.5～2: 100.
6. the present invention further provides a kind of ZnO nano particle of precious metal doping, it is characterized in that: described ZnO/Ag, ZnO/Pd nano particle, its precious metal ion are finally modified ZnO with the form of simple substance, and crystallite dimension is between 41～46nm; Absorption spectrum ranges is in the visible region of 400～800nm.
7. according to the ZnO nano particle of the described a kind of precious metal doping of claim 1～6; It is characterized in that: described ZnO/Ag nano particle, the diffraction maximum of its ZnO belongs to hexagonal wurtzite structure, and the space crystal group belongs to P63mc (186); Point lattice constant a=b=0.3249nm, c=0.5205nm; The diffraction maximum of its Ag and standard diagram JCPDF:87-0717 coincide, and the space crystal group belongs to Fm-3m (225), point lattice constant a=b=c=4.086nm.
8. according to the ZnO nano particle of the described a kind of precious metal doping of claim 1～6; It is characterized in that: described ZnO/Pd nano particle, the diffraction maximum of its ZnO belongs to hexagonal wurtzite structure, and the space crystal group belongs to P63mc (186); Point lattice constant a=b=0.3249nm, c=0.5205nm; The diffraction maximum of its Pd and standard diagram JCPDF:88-2335 coincide, and the space crystal group belongs to Fm-3m (225), point lattice constant a=b=c=3.900nm.
9. the purposes according to the ZnO nano particle of claim 1,7,8 arbitrary described a kind of precious metal dopings is characterized in that: the photochemical catalyst that described precious metal doping ZnO nano particle is degraded as uns-dimethylhydrazine waste water; The usage of described photochemical catalyst is that the ZnO/Ag or the ZnO/Pd nano particle that prepare are joined in the low concentration uns-dimethylhydrazine waste water; Light-catalyst ZnO/the Ag that adds or the concentration of ZnO/Pd nano particle are 100～300mg/L; Stirring makes ZnO/Ag or ZnO/Pd nanoparticulate dispersed even, places catalytic degradation low concentration uns-dimethylhydrazine waste water under the outdoor sunshine.
10. according to the purposes of the ZnO nano particle of the said a kind of precious metal doping of claim 9, it is characterized in that: described photochemical catalyst joins that back catalytic degradation irradiation time under sunshine is 0.5～4 hour in the uns-dimethylhydrazine low concentration wastewater; Under the ultraviolet light ZnO/Ag and ZnO/Pd to uns-dimethylhydrazine waste water the most degradation rate be respectively 92.7% and 76.8%; More than 80%, wherein when the mol ratio of Ag and Zn was 0.5: 100, degradation rate was 92.7% to the degradation rate of uns-dimethylhydrazine waste water for ZnO/Ag and ZnO/Pd under the sunshine; Degradation rate is than being 87.2.% when the mol ratio of Pd and Zn is 1: 100. Used ZnO/Ag or ZnO/Pd nano particle can be reused after centrifugalizing.
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| CN103071493A (en) * | 2013-01-11 | 2013-05-01 | 河海大学 | Preparation method of hollow Ag/Zno microsphere photocatalyst |
| CN103084177A (en) * | 2013-01-31 | 2013-05-08 | 华东师范大学 | Non-template preparation method of precious metal-modified zinc oxide (ZnO) nano-composite material |
| CN103159410A (en) * | 2013-03-14 | 2013-06-19 | 吉林大学 | Hydrothermal preparation method of p-type sulfur/silver codoped zinc oxide film |
| CN103908964A (en) * | 2014-04-08 | 2014-07-09 | 河南理工大学 | Precious metal doped zinc oxide nano powder body and preparation and application thereof |
| CN104355443A (en) * | 2014-10-30 | 2015-02-18 | 兰州大学 | Treatment method for unsymmetrical dimethylhydrazine-containing wastewater |
| CN104787841A (en) * | 2015-04-30 | 2015-07-22 | 扬州大学 | Preparation method of three-dimensional macroporous carbon/carbon nanotube/titanium dioxide/silver composite material capable of catalytically degrading unsymmetrical dimethylhydrazine |
| CN105709726A (en) * | 2014-12-05 | 2016-06-29 | 沈阳药科大学 | Method for preparing supported precious metal/zinc oxide hybrid nanometer materials |
| CN107189584A (en) * | 2017-06-20 | 2017-09-22 | 南京林业大学 | Sour coating of a kind of photocatalysis aqueous polyacrylamide and preparation method thereof |
| CN109847743A (en) * | 2019-03-29 | 2019-06-07 | 福州大学 | A kind of preparation that Ru adulterates ZnO/Ti composite oxides electrode and its application in photoelectric catalysis degrading organic |
| CN109999781A (en) * | 2019-03-27 | 2019-07-12 | 江苏金环环保设备有限公司 | A kind of boracic rare earth oxide composite material and its processing method handling uns-dimethylhydrazine waste water |
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| CN103159410A (en) * | 2013-03-14 | 2013-06-19 | 吉林大学 | Hydrothermal preparation method of p-type sulfur/silver codoped zinc oxide film |
| CN103908964A (en) * | 2014-04-08 | 2014-07-09 | 河南理工大学 | Precious metal doped zinc oxide nano powder body and preparation and application thereof |
| CN104355443B (en) * | 2014-10-30 | 2016-04-06 | 兰州大学 | A kind for the treatment of process of the waste water containing unsymmetrical dimethyl hydrazine |
| CN104355443A (en) * | 2014-10-30 | 2015-02-18 | 兰州大学 | Treatment method for unsymmetrical dimethylhydrazine-containing wastewater |
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| CN109999781B (en) * | 2019-03-27 | 2019-11-08 | 江苏金环环保设备有限公司 | A kind of boracic rare earth oxide composite material and its processing method handling uns-dimethylhydrazine waste water |
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