阅读说明：本技术 三氧化钨气敏膜材料、三氧化钨基复合气敏膜材料、制备方法和应用 (Tungstic acid air-sensitive membrane material, tungstic acid base composite air-sensitive membrane material, preparation method and application ) 是由 王明松 王宜炜 葛传鑫 李晓静 刘桂武 乔冠军 于 2019-07-11 设计创作，主要内容包括：本发明公开了一种三氧化钨气敏膜材料、三氧化钨基复合气敏膜材料、制备方法和应用。通过在电极基板上利用溶液原位沉积直接制备纳米结构三氧化钨薄气敏材料,利用溶胶凝胶法在制得的三氧化钨薄膜上进行第二相氧化物复合,获得三氧化钨基复合气敏材料。本发明的优点在于可在电极基板上直接沉积生长纳米结构三氧化钨薄膜；所制备的纳米结构三氧化钨薄膜以及基于纳米结构三氧化钨的复合薄膜具有垂直基片生长的纳米片所形成的网络状结构。本发明具有高效、成本低廉、工艺简单的优点,适合于工业化生产。所得纳米结构三氧化钨薄膜具有较大的比表面积,可有效克服纳米颗粒之间的团聚问题,对NO<Sub>2</Sub>、H<Sub>2</Sub>S等气体具有良好的气敏响应,具有极好的气敏应用前景。(The invention discloses a kind of tungstic acid air-sensitive membrane materials, tungstic acid base composite air-sensitive membrane material, preparation method and application.By utilizing solution in-situ deposition directly to prepare the thin gas sensitive of nanostructure tungstic acid on the electrode substrate, it is compound to carry out the second phase oxide on WO 3 film obtained using sol-gal process, obtains tungstic acid base composite air-sensitive material.The advantage of the invention is that nanostructure WO 3 film can be grown Direct precipitation on the electrode substrate；There is the nanometer sheet of vertical substrate growth to be formed by network-like structure for prepared nanostructure WO 3 film and the laminated film based on nanostructure tungstic acid.The present invention has the advantages that efficient, low in cost, simple process, is suitable for industrialized production.Gained nanostructure WO 3 film has biggish specific surface area, the agglomeration traits between nano particle can be effectively overcome, to NO 2 、H 2 The gases such as S are responded with good air-sensitive, have fabulous air-sensitive application prospect.)

1. a kind of preparation method of tungstic acid air-sensitive membrane material, which comprises the following steps:

(1) sodium tungstate and organic acid or ammonium salt are weighed first, is dissolved in deionized water under agitation, and it is molten that dilute hydrochloric acid is then added Liquid is stirred at room temperature, and configures clear WO₃Precursor solution；

(2) nanostructure WO 3 film is deposited directly on electrode base sheet using chemical bath.

2. the preparation method of tungstic acid air-sensitive membrane material according to claim 1, it is characterised in that: institute in step (2) It states chemical bath and prepares WO 3 film method particularly includes:

The ceramic substrate for being printed on electrode cleaned up is immersed in WO₃In precursor solution, solution temperature is heated to 50~ 180 DEG C, 0.5~10 hour is kept the temperature at such a temperature, takes out ceramic substrate, cleaning dries, it is heat-treated 1 at 300~400 DEG C~ 50 hours obtained nanostructure WO₃Air-sensitive film.

3. the preparation method of tungstic acid air-sensitive membrane material according to claim 2, it is characterised in that: sodium tungstate with it is organic The mass ratio of acid or ammonium salt is 0.5~30.Deionization needed for being added by the dosage that 100mL deionized water is added in every gram of sodium tungstate Water is stirred at room temperature 0.5 hour, the dilute hydrochloric acid solution that 6~20mL concentration is 3mol/L is then added, and continuation is stirred at room temperature It mixes 0.5 hour, obtains clarification precursor solution.

4. the preparation method of tungstic acid air-sensitive membrane material according to claim 2, it is characterised in that: the organic acid is Citric acid or oxalic acid, ammonium salt are ammonium oxalate or ammonium sulfate.

5. the tungstic acid air-sensitive membrane material of the preparation method preparation of tungstic acid air-sensitive membrane material according to claim 1, It is characterized in that, the tungstic trioxide nano-slice cross arrangement of nano-scale is grid-shaped in the tungstic acid air-sensitive film, it is described Tungstic trioxide nano-slice is grown perpendicular to substrate.

6. tungstic acid base composite air-sensitive film MATERIALS METHODS is prepared based on the tungstic acid air-sensitive membrane material described in claim 5, It is characterized in that,

Acquired nanostructure WO 3 film is immersed the second phase oxidation by the precursor sol for configuring the second phase oxide In object precursor sol, through being heat-treated after lifting, the second phase oxygen is deposited on nano tungsten trioxide thin film using sol-gal process Compound obtains tungstic acid base composite air-sensitive membrane material, controls the second phase by repeated impregnations-lifting-heat treatment number of repetition The thickness of oxide.

7. preparing the method for tungstic acid base composite air-sensitive membrane material according to claim 6, it is characterised in that: when described Two phase oxides are SnO₂、ZnO、CdO、TiO₂, one of NiO, CuO, used in the precursor sol for preparing the second phase oxide Metal salt is stannous chloride, zinc acetate, cadmium acetate, butyl titanate, nickel acetate or copper acetate；Metal salt concentrations are in colloidal sol 0.1~0.7mol/L；Solvent for use is dehydrated alcohol, and stabilizer is diethanol amine；When second phase oxide is SiO₂, match Making metal salt used in the precursor sol of the second phase oxide is tetraethyl orthosilicate, and solvent for use is dehydrated alcohol, the stabilization Agent is concentrated hydrochloric acid.

8. the tungstic acid base composite air-sensitive membrane material of method preparation according to claim 6, it is characterised in that: described three The tungstic trioxide nano-slice cross arrangement of nano-scale is grid-shaped in tungsten oxide air-sensitive film, and the tungstic trioxide nano-slice is vertical It is grown in substrate；Second phase oxide nano particle is attached on tungstic trioxide nano-slice.

9. tungstic acid air-sensitive membrane material according to claim 5 is used for detection gas.

10. tungstic acid base composite air-sensitive membrane material is used for detection gas according to claim 8.

Technical field

The present invention relates to metal oxide film field of material preparation, and in particular to a kind of tungstic acid air-sensitive membrane material, three Tungsten oxide base composite air-sensitive membrane material, preparation method and application.

Background technique

With the development and the improvement of people's living standards of social economy, the environment that people live to oneself, especially Air quality proposes more and more requirements, and inflammable to indoor and outdoor low concentration, explosive and toxic gas detection is also increasingly Pay attention to.Gas sensor is a kind of sensor for detecting specific gas.It is utilized is occurred between under test gas and sensitive material Physical-chemical reaction, be that electrical signal form exports by the concentration of under test gas and conversion, according to the variation of electric signal from And confirm gas componant and concentration.Itself resistance value when resistance-type gas sensor is contacted using semiconductor material and gas Variation is to detect specific gas, and sensitive material used is based on metal oxide, such as SnO₂、ZnO、WO₃Deng with production method Simply, high sensitivity, detection limit it is low, long service life, it is at low cost the advantages that.

WO₃It is a kind of typical n-type semiconductor, forbidden bandwidth is less than 3.0eV.Air-sensitive WO₃Material is mostly nano-powder, As CN201610277867.0 discloses a kind of rodlike WO₃The preparation method of gas-sensitive nano material；CN201610952845.X is public A kind of WO for ammonia gas sensor is opened₃The preparation method of sensitive material, WO used₃Sensitive material is noble metal Au, Ru Or the nanostructure WO of Pd modification₃Powder；CN201720513105.6 discloses a kind of WO₃Film gas sensor is used thin Film is WO₃Nanometer rods powdery pulp is coated to be made.Since gas sensitive need to be deposited on electrode surface film forming by air-sensitive measurement, because The typical process that this nano-powder makes gas sensitive device is to disperse nano-powder in organic bond to form slurry, then will Slurry coating is printed on electrode base sheet, organic bond is removed finally by heat treatment, to obtain air-sensitive membrane material.By This was made in slurry as it can be seen that be related to secondary operation to powder from nano-powder to air-sensitive membrane material is made on the electrode The processes such as the grinding in journey may destroy nanostructure, and it is generally thicker (be greater than 10 microns) to apply resulting membrane material, receives Accumulation between rice grain can reduce effective contact area with gas.

Compound between conductor oxidate forms n-n hetero-junctions (such as WO₃-SnO₂、WO₃- ZnO etc.) or p-n it is heterogeneous Tie (such as WO₃-NiO、WO₃- CuO etc.), thus generate the migration of carrier between two oxides or form space charge layer, To improve the air-sensitive performance of material.Such as WO₃-SnO₂Composite material has higher NO compared to single oxide₂It responds sensitive It spends (150 (2010) 749-755 of Sensors and Actuators B), WO₃With CuO is compound greatly improves material pair H₂Response sensitivity (the Particle&Particle Systems Characterization 33 (2016) 15-of S gas 20)。

Summary of the invention

In view of the deficiencies of the prior art, it is an object of that present invention to provide a kind of WO of nano-scale₃Film gas sensitive and its In-situ deposition method；Based on the WO₃The tungstic acid base composite air-sensitive membrane material of film gas sensitive preparation, preparation method；With And purposes.

The object of the invention is realized by following proposal:

A kind of preparation method of tungstic acid air-sensitive membrane material, which comprises the following steps:

(1) sodium tungstate and organic acid or ammonium salt are weighed first, is dissolved in deionized water under agitation, and dilute salt is then added Acid solution is stirred at room temperature, and configures clear WO₃Precursor solution；

(2) nanostructure WO 3 film is deposited directly on electrode base sheet using chemical bath.

Further, chemical bath described in step (2) prepares WO 3 film method particularly includes:

The ceramic substrate for being printed on electrode cleaned up is immersed in WO₃In precursor solution, solution temperature is heated to 50~180 DEG C, 0.5~10 hour is kept the temperature at such a temperature, takes out ceramic substrate, cleaning is dried, at 300~400 DEG C at heat Manage 1~50 hour obtained nanostructure WO₃Air-sensitive film.

Further, the mass ratio of sodium tungstate and organic acid or ammonium salt is 0.5~30.100mL is added by every gram of sodium tungstate Required deionized water is added in the dosage of deionized water, is stirred at room temperature 0.5 hour, and 6~20mL concentration is then added and is The dilute hydrochloric acid solution of 3mol/L continues to be stirred at room temperature 0.5 hour, obtains clarification precursor solution.

Further, the organic acid is citric acid or oxalic acid, and ammonium salt is ammonium oxalate or ammonium sulfate.

The tungstic acid air-sensitive membrane material of the preparation method preparation of the tungstic acid air-sensitive membrane material, which is characterized in that The tungstic trioxide nano-slice cross arrangement of nano-scale is grid-shaped in the tungstic acid air-sensitive film, the tungsten trioxide nano Piece is grown perpendicular to substrate.

Tungstic acid base composite air-sensitive film MATERIALS METHODS is prepared based on the tungstic acid air-sensitive membrane material, feature exists In,

Acquired nanostructure WO 3 film is immersed the second phase by the precursor sol for configuring the second phase oxide In oxide precursor colloidal sol, through being heat-treated after lifting, second is deposited on nano tungsten trioxide thin film using sol-gal process Phase oxide obtains tungstic acid base composite air-sensitive membrane material, passes through repeated impregnations-lifting-heat treatment number of repetition control the The thickness of two phase oxides.

Further, when second phase oxide is SnO₂、ZnO、CdO、TiO₂, one of NiO, CuO, prepare the Metal salt used in the precursor sol of two phase oxides be stannous chloride, zinc acetate, cadmium acetate, butyl titanate, nickel acetate or Copper acetate；The concentration of metal salt is 0.1~0.7mol/L in colloidal sol；Solvent for use is dehydrated alcohol, and stabilizer is diethanol amine； When second phase oxide is SiO₂, preparing metal salt used in the precursor sol of the second phase oxide is tetraethyl orthosilicate, Solvent for use is dehydrated alcohol, and the stabilizer is concentrated hydrochloric acid.

The tungstic acid base composite air-sensitive membrane material of the method preparation, it is characterised in that: the tungstic acid air-sensitive film The tungstic trioxide nano-slice cross arrangement of middle nano-scale is grid-shaped, and the tungstic trioxide nano-slice is grown perpendicular to substrate； Second phase oxide nano particle is attached on tungstic trioxide nano-slice.

The tungstic acid air-sensitive membrane material is used for detection gas.

The tungstic acid base composite air-sensitive membrane material is used for detection gas.

Compared with the prior art, the present invention has the advantages that can one-step method realization nanostructure is deposited on electrode base sheet WO₃Film, effectively prevent being made of nano-powder slurry again in coating process nanostructure destroy, accumulation the problems such as；It is based on WO₃Laminated film can further improve material air-sensitive response, selectivity etc. performances.

Detailed description of the invention

Fig. 1 is nanostructure WO prepared by embodiment 1₃The scanning electron microscope diagram of film.

Fig. 2 is nanostructure WO prepared by embodiment 2₃The scanning electron microscope diagram of film.

Fig. 3 is nanostructure WO prepared by embodiment 3₃The scanning electron microscope diagram of film.

Fig. 4 is nanostructure WO prepared by embodiment 3₃Air-sensitive film is at 100 DEG C to various concentration NO₂The dynamic of gas is rung Answer curve.

Fig. 5 is nanostructure WO prepared by embodiment 4₃/SiO₂The scanning electron microscope diagram of laminated film.

Fig. 6 is nanostructure WO prepared by embodiment 4₃/SiO₂Laminated film is at 250 DEG C to various concentration H₂S gas Dynamic response curve.

Fig. 7 is WO prepared by embodiment 5₃/SnO₂The scanning electron microscope diagram of composite air-sensitive nano-sized membrane.

Fig. 8 is WO prepared by embodiment 5₃/SnO₂Composite air-sensitive film is at 100 DEG C to various concentration NO₂The dynamic of gas Response curve.

Specific embodiment

The following examples are not intended to limit the scope of the invention to further explanation of the invention.