CN103531363A - Preparation method of slurry for dye-sensitized solar cell nano-TiO2 film photoanode - Google Patents

Abstract

The invention belongs to the field of solar cells, and in particular relates to a preparation method of a slurry for a nano- _TiO2 film photoanode of a dye-sensitized solar cell. The technical problem to be solved by the present invention is that the preparation method of the slurry required for the existing nano- _TiO2 photoanode film has high cost and complicated process. The solution of the present invention to solve the above-mentioned technical problems is to provide a preparation method of slurry for nano- _TiO2 film photoanode of dye-sensitized solar cells, comprising the following steps: a. heating and hydrolyzing the industrial titanium solution, then centrifugally sedimenting the hydrolysis system, removing the supernatant and washing to obtain metatitanic acid; b. adding a debonding agent to the metatitanic acid for degumming to obtain metatitanic acid slurry; c. adding additives to make the metatitanic acid slurry evenly dispersed. The method provided by the invention is simple to implement, the performance of the slurry can be flexibly adjusted along with the process parameters, and the obtained _metatitanic acid slurry has good dispersibility and strong stability. material provides a new method.

Description

Preparation method of slurry for dye-sensitized solar cell nano-TiO2 film photoanode

technical field

The invention belongs to the field of solar cells, and in particular relates to a preparation method of a slurry for a nano- _TiO2 film photoanode of a dye-sensitized solar cell.

technical background

The nano-semiconductor porous membrane electrode is the core part of the dye-sensitized solar cell (DSSC). It is the adsorption carrier of the dye molecule, the electron acceptor of the dye molecule in the DSSC, and also the transport layer of the electron, which is decisive for the performance of the DSSC. Influence. The raw materials for its production generally use n-type semiconductor metal oxides such as TiO ₂ , SnO ₂ , and ZnO, which are cheap and have a wide band gap. Among them, anatase TiO ₂ has a band gap of 3.2eV, has excellent photoelectric properties, high optical, electrical, and chemical stability, and is the best material for preparing nano-semiconductor porous membrane electrodes. At present, most of the preparation methods of nano-semiconductor porous membranes use screen printing method, scrape coating method (scalpel method), spin coating method and so on. The use of these methods are all based on the titanium-containing compound (generally nano-TiO ₂ ) slurry with proper concentration, good dispersion and stability. The precursor of the titanium compound in the slurry adopts commercial nano- _TiO2 powder in large quantities. In recent years, in order to facilitate the control of the performance of the slurry to obtain better photoelectric conversion efficiency of DSSC, various forms of titanium-containing soluble compounds have also been used as raw materials to synthesize and prepare nano- _TiO2 photoanode films through various processes. of slurry.

1. Synthesize slurry with commercial nano- _TiO2 powder as raw material

Now, the commodity nano-TiO ₂ widely recognized by various researchers is degussa P25, which is a product imported from Germany. It belongs to the mixed crystal type, and the weight ratio of anatase and rutile is about 80/20. Due to the mixing of the two structures, the defect density in the TiO ₂ lattice is increased, and the concentration of carriers is increased, so that electrons, holes The increase in the number makes it have a stronger ability to capture solution components (water, oxygen, organic matter) on the surface of TiO ₂ .

The slurry synthesized with P25 as raw material can be divided into two types: water-based and terpineol-based. For temporary production of slurry that does not require long-term storage, water-based slurry is generally used. It mainly uses acetylacetone as a dispersant, and then mixes with appropriate surfactants or other polymer substances. After a period of manual or mechanical grinding, it becomes a slurry that can be used for coating. Among surfactants, emulsifier OP10 and Triton X-100 are the most used. Polyethylene glycols with different molecular weights are the most widely used polymer compounds, such as PEG20000 (polyethylene glycol, molecular weight 20000), PEG600 (polyethylene glycol, molecular weight 600), PEG2000 (polyethylene glycol, molecular weight is 2000), etc., its molecular weight is different, and its role also changes accordingly. In some undemanding simplified slurry synthesis processes, very few slurry components are used. If someone washes the nano-powder with alcohol, only add PEG20000 and grind it by hand to coat evenly. Some people only add ethylene glycol in the ethanol aqueous solution, and apply the film directly after ultrasonic and manual grinding. This kind of production has poor dispersibility, easy agglomeration, extremely poor stability, and no scale application significance.

For the requirement of preparing large quantities and long-term storage, terpineol-based slurry is generally used. Similar to water-based slurry, acetylacetone is generally used as a dispersant in oil-based slurry, ethyl cellulose is used as a binder, and PEG2000 can be added as a pore-forming agent if necessary to increase the specific surface area of the prepared membrane . This kind of slurry contains a lot of organic matter, and the production cost is high; during high temperature treatment, due to the volatilization and decomposition of organic matter, a large amount of harmful waste gas is released.

2. Using titanium alkoxide as raw material

In the synthesis of DSSC photoanode preparation slurry, two titanium alkoxides, butyl titanate and titanium isopropoxide, are mainly used as precursors, and the former is used more. Generally, the required powder is synthesized according to the sol-gel process or the slurry is directly synthesized. In this process, the above-mentioned titanium organic compound is first prepared into a corresponding solution, and then an appropriate amount of water is added to hydrolyze the titanium and transform into a titanium colloidal dispersion system. glue. The corresponding powder can be obtained by heat-treating the gel. But more often in order to improve performance, it is often combined with hydrothermal process.

Quickly add butyl titanate to water, adjust and stir to hydrolyze, then filter with a sand core funnel. After the hydrolyzate is washed, it is added to a certain concentration of organic alkali aqueous solution (such as tetramethylammonium hydroxide, etc.). The mixture was reacted at 80°C for 12h under sealed conditions, then moved into a hydrothermal reaction kettle and reacted at 200°C for 12h to form a milky white colloid. After adding PEG20000, adjusting the concentration and viscosity, it can be used for film coating. This is a preparation method of peptization combined with hydrothermal, which uses relatively expensive titanium alkoxide and organic base as raw materials, and the process takes a long time.

Titanium isopropoxide was added into the acetic acid solution and vigorously stirred to make it hydrolyzed, and then hydrothermally treated at 250°C. Then ethyl cellulose in ethanol was added, and the slurry was properly concentrated. Add terpineol, polyacrylate and TritonX-100, stir evenly and then use it for film coating. The raw material of this method is expensive and unstable, and it is an all-organic system, and high-temperature treatment releases a large amount of harmful waste gas.

Contents of the invention

The technical problem to be solved by the present invention is that the preparation method of the slurry required for the existing nano- _TiO2 photoanode film has high cost and complicated process.

The solution of the present invention to solve the above-mentioned technical problems is to provide a kind of preparation method of the slurry for dye-sensitized solar cell nano- _TiO film photoanode, comprising the following steps:

a. Heat and hydrolyze the industrial titanium liquid, centrifugally settle the hydrolysis system, remove the supernatant, and then wash the remaining part with 0.05-0.35mol/L dilute acid, centrifugally settle, remove the supernatant, and wash repeatedly until iron-free After ionization, wash with water until the pH is 5.5-7.0 to obtain metatitanic acid;

b. adding a debonding agent to the metatitanic acid for degumming to obtain a metatitanic acid slurry;

c. Add additives to disperse the metatitanic acid slurry evenly.

Wherein, in the preparation method of the slurry for the nano- _TiO2 film photoanode of the dye-sensitized solar cell, the industrial titanium liquid described in step a is an intermediate material in the process of producing titanium white by the sulfuric acid method. It can be the titanium liquid material processed in each stage of the process from the filtrate after the acid hydrolysis of titanium ore to the process before hydrolysis, and is not affected by the change of the titanium liquid composition caused by the treatment in this stage of the industrial production process.

Wherein, in the preparation method of the slurry for nano-TiO ₂ film photoanode of dye-sensitized solar cells, the heating temperature in step a is 110-250° C., and the hydrolysis time is 1-10 h.

Wherein, in the preparation method of the slurry for the nano- _TiO2 film photoanode of the dye-sensitized solar cell, the relative centrifugal force of the centrifugal sedimentation in step a is 2536g-9509g.

Wherein, in the preparation method of the slurry for the nano- _TiO2 film photoanode of the dye-sensitized solar cell, a reducing agent or a complexing agent is added in the dilute acid washing process described in step a. The added amount of the reducing agent or complexing agent is 60%-150% by mass of titanium. Preferably, the reducing agent is any one of hydroxylamine hydrochloride and ascorbic acid, and the complexing agent is any one of citric acid, tartaric acid and ammonium fluoride.

Wherein, above-mentioned dye-sensitized solar cell nano- _TiO2 film photoanode in the preparation method of slurry, the washing described in step a to contain no iron ion is to adopt 20% ammonium thiocyanate solution to check the supernatant of washing to colorless.

Wherein, in the preparation method of the slurry for nano- _TiO2 film photoanode of dye-sensitized solar cells, the dilute acid described in step a is one of dilute citric acid, dilute tartaric acid, dilute hydrochloric acid and dilute sulfuric acid.

Wherein, in the preparation method of the slurry for nano- _TiO2 film photoanode of dye-sensitized solar cells, the degumming agent described in step b is at least one of tartaric acid, citric acid, hydrochloric acid or phosphoric acid.

Wherein, in the preparation method of the slurry for the nano- _TiO2 film photoanode of the dye-sensitized solar cell, the addition amount of the degumming reagent in step b is 0.01-0.48 g/mL industrial titanium solution.

Wherein, in the preparation method of the slurry for nano TiO ₂ film photoanode of dye-sensitized solar cells, the degumming temperature in step b is 20-90° C., and the degumming time is 4-30 h.

Wherein, in the preparation method of the above-mentioned nano _- TiO film photoanode slurry for dye-sensitized solar cells, the additives described in step c and their addition proportions are: 400% to 900% terpineol, 0.5 %~6% ethyl cellulose, 0.005%~0.1% Triton X-100, 0.2%~1% acetylacetone, 1%~6% PEG2000, 1%~10% hydroxyethyl cellulose At least one of element, 0.5%-2% PVA, 0.1%-1% acetylacetone, 0.02%-0.15% OP emulsifier, 0.1%-0.5% humectant; wherein, the humectant is polyethylene Any of glycol, butylene glycol, sorbitol, glycerin, propylene glycol, xylitol, and N,N-dimethylformamide.

The beneficial effects of the present invention are: (1) The solid phase component of the electrode slurry prepared by the method of the present invention is mainly metatitanic acid, and the metatitanic acid undergoes a decomposition reaction under high temperature treatment after being coated with it It is easy to obtain an electrode film with high porosity and high specific surface area by converting it into nano-titanium dioxide, which is beneficial to the improvement of the performance of the battery made with it. (2) The electrode slurry prepared by the present invention has an effective solid phase component of metatitanic acid, which is a kind of hydrous titanium oxide, which is easier to make into a water-based slurry, greatly reduces the amount of organic matter, reduces costs, and at the same time It also reduces the toxic and harmful volatiles produced by the decomposition of organic matter during the high-temperature treatment of the membrane, and reduces the degree of pollution to the environment. (3) The principle adopted in the present invention is industrial titanium liquid, which is an intermediate product in the production process of sulfuric acid titanium dioxide. It has abundant sources and low price. than, the cost is lower. Starting from the dissolved industrial titanium liquid, it is more convenient to add other ingredients into the slurry to adjust the film performance of the slurry. The dopant and titanium can be uniformly mixed at the molecular level. Compared with the solid-phase doping energy Get a better modification effect. Moreover, industrial titanium liquid itself contains iron and sulfur components. Research data show that within a certain content range, the presence of these two components can improve the performance of electrodes prepared from slurry synthesized from titanium liquid. The metatitanic acid obtained by hydrolysis of industrial titanium liquid is used as the dispersed phase, and when terpineol is used as the dispersion medium, it can obtain the same stability and dispersibility as the slurry synthesized by using traditional commercial nano-materials; when water is used as the dispersion medium It has good long-term stability and dispersibility, and is suitable for the synthesis and application of large-scale slurry. (4) In the method provided by the present invention, the entire process is operated at room temperature, does not involve high temperature treatment, and does not cause grain growth of nanoparticles at high temperature, which is convenient for particle size control; and full wet chemistry is used process, without drying and roasting treatment, so there is no need for related drying, roasting, crushing, grinding and other links and corresponding equipment, saving investment and reducing energy consumption; For coagulation methods such as hydrolysis, the process control is relatively extensive, the operation is simple, and the treatment process is short.

The method provided by the invention is simple to implement, the performance of the slurry can be flexibly adjusted along with the process parameters, and the obtained _metatitanic acid slurry has good dispersibility and strong stability. material provides a new method.

Detailed ways

The preparation method of slurry for dye-sensitized solar cell nanometer _TiO film photoanode, comprises the following steps:

a. Heat the industrial titanium liquid at a heating rate of 0.5-10°C/min to 110-250°C for 1-10 hours, then centrifuge the hydrolysis system to remove the supernatant, and then use 0.05-0.35mol/L for the remaining part Washing with dilute acid, centrifugal sedimentation, removing the supernatant, washing repeatedly until iron ions are free, and then washing with water until the pH is 5.5-7.0 to obtain metatitanic acid;

b. Adding a degumming agent to the metatitanic acid, and degumming at 20-90°C for 4-30 hours to obtain a metatitanic acid slurry; the amount of the degumming reagent added is 0.01-0.48 g/mL industrial titanium solution.

c. Add additives to disperse the metatitanic acid slurry evenly.

Wherein, in the preparation method of the slurry for the nano- _TiO2 film photoanode of the above-mentioned dye-sensitized solar cell, the industrial titanium liquid described in step a is an intermediate material in the process of producing titanium dioxide by the sulfuric acid method. It can be the titanium liquid material processed in each stage of the process from the filtrate after the acid hydrolysis of titanium ore to the process before hydrolysis, and is not affected by the change of the titanium liquid composition caused by the treatment in this stage of the industrial production process.

Wherein, in step a of the above-mentioned method, the hydrolysis methods of industrial titanium liquid include: direct hydrothermal hydrolysis without adding water, direct hydrothermal hydrolysis with water added, heating hydrolysis with water under normal pressure, external field (microwave field, ultrasonic field or both) combination) forced hydrolysis. The heating rate of hydrothermal hydrolysis of industrial titanium liquid is 0.5-10°C/min, the charging ratio of industrial titanium liquid hydrothermal hydrolysis reactor is 10%-90%, and the amount of water added for hydrothermal hydrolysis is 0-200% (relatively The volume of industrial titanium liquid), there are three cooling methods after hydrothermal hydrolysis: rapid cooling with running water, cooling in indoor air and cooling with furnace; the hydrolysis rate of industrial titanium liquid can reach 60-99%.

Wherein, the relative centrifugal force of the centrifugal sedimentation in step a of the above method is 2536g-9509g. Using centrifugal sedimentation as a means of solid-liquid separation makes it possible to directly hydrolyze industrial titanium liquid into an ultrafine particle system, and the solid-liquid sedimentation time is very short and the operation is simple.

Wherein, a reducing agent or a complexing agent is added in the dilute acid washing process described in step a of the above method. The added amount of the reducing agent or complexing agent is 60%-150% by mass of titanium. Preferably, the reducing agent is any one of hydroxylamine hydrochloride and ascorbic acid, and the complexing agent is any one of citric acid, tartaric acid and ammonium fluoride. In the washing process of industrial titanium liquid hydrolyzate, a completely degradable or completely volatile reducing agent or complexing agent is added to facilitate the rapid and thorough purification of impurities.

Wherein, in the preparation method of the slurry for nano- _TiO2 film photoanode of dye-sensitized solar cells, the dilute acid described in step a is dilute citric acid, dilute tartaric acid, dilute hydrochloric acid, dilute sulfuric acid and the like.

Wherein, above-mentioned dye-sensitized solar cell nano- _TiO2 film photoanode in the preparation method of slurry, the washing described in step a to contain no iron ion is to adopt 20% ammonium thiocyanate solution to check the supernatant of washing to colorless.

Wherein, the degumming reagent described in step b of the above method is at least one of tartaric acid, citric acid, hydrochloric acid or phosphoric acid. The ultrafine particle dispersion system of fresh metatitanic acid produced by the hydrolysis of industrial titanium liquid is obtained by degumming. The way of adding the debonding agent can be a solution or a solid. If it is solid, the degumming process is carried out in a closed (low temperature <50°C) environment, or in a container with a condensing reflux device.

Wherein, the additives described in step c of the above method and their addition proportions are: 400% to 900% of terpineol, 0.5% to 6% of ethyl cellulose, and 0.005% to 0.1% of kojira in terms of titanium mass. Tong X-100, 0.2%~1% acetylacetone, 1%~6% PEG2000, 1%~10% hydroxyethyl cellulose, 0.5%~2% PVA, 0.1%~1% acetylacetone , 0.02% to 0.15% of OP emulsifier, 0.1% to 0.5% of at least one moisturizer; wherein the moisturizer is polyethylene glycol, butylene glycol, sorbitol, glycerin, propylene glycol, xylitol, Any one of N,N-dimethylformamide.

In the present invention, the degumming of large particles of metatitanic acid and the preparation of nanometer metatitanic acid slurry are very important for obtaining the electrode film preparation slurry with good performance. During degumming, the solubility of tartaric acid in water is greatly affected by temperature, so its application effect is also related to temperature. The higher the temperature, the greater its solubility and the better the effect. Citric acid has good solubility, strong complexing ability with titanium, and good degumming effect. The above two reagents are weak in acidity, which is convenient for subsequent processing. Hydrochloric acid has a good degumming effect and is volatile, but it is highly acidic, which is not conducive to subsequent processing and needs to be properly neutralized. Phosphoric acid has good degumming ability, complex production and poor volatility. These reagents have a good degumming effect when applied alone or in combination, but when the amount added is less than 10%, it is found that the degumming effect is very insignificant; and when the amount is too large (>500%), the The slurry preparation process will be greatly disturbed, affecting the properties of the obtained slurry.

When preparing slurry, the slurry composition includes, in addition to metatitanic acid, solvent (terpineol or water), binder (PVA, ethyl cellulose, hydroxyethyl cellulose, etc.), dispersant (acetyl Acetone, emulsifier OP10, etc.), pore forming agent (PEG, etc.), humectant, etc. The addition of these reagents can make the degummed metatitanic acid disperse, stabilize, and not agglomerate in the dispersed phase, and the particle size grows slowly, and makes the slurry easy to coat, and the film has good leveling properties. The porosity of the membrane is high, the specific surface area is large, and the adhesion of the membrane is good. But these properties also depend on the amount of reagents added. Therefore, if the above-mentioned reagents are added in an improper amount, it will be difficult to obtain a slurry that meets the requirements for manufacturing the DSSC nano-titanium dioxide photoanode film.

Example 1:

Mix the industrial titanium liquid and water at a volume ratio of 5:6, put them into the condensing reflux device, and heat under reflux at an oil bath temperature of 114°C for 11 hours. The hydrolysis system was centrifugally settled at a relative centrifugal force of 9509g for 6 minutes. After the supernatant was poured off, the lower layer was washed by adding 0.1mol/L dilute sulfuric acid solution, and the supernatant was removed by centrifugal sedimentation. After checking that the washing supernatant is colorless, it is washed with water until the pH is 5.5-7.0 to obtain metatitanic acid.

Add tartaric acid at 0.046g/mL industrial titanium solution, degumming at 60°C for 26 hours to obtain metatitanic acid slurry.

After the end, add 5% PVA solution by volume ratio of 5% PVA solution: metatitanic acid slurry volume=1:5, add the ethanol solution of acetylacetone with 22% metatitanic acid slurry volume (volume ratio is acetylacetone : ethanol = 1: 1), then add 5% (based on titanium mass) of N,N-dimethylamide, and stir for 3 hours to make the slurry evenly dispersed.

The hydrolysis rate of industrial titanium liquid reaches 83.22%.

Dilute the slurry with water to a mass concentration of 1%. When measuring, take 100mL of the diluted slurry, place it in a 100mL stoppered measuring cylinder, cover the stopper, and check the volume of the unclarified part after standing for seven days. The seven-day sedimentation volume of the obtained slurry reaches 95mL, and the slurry has good stability.

The concentration of titanium dioxide in the slurry reaches 21.13% (mass percentage concentration). After the slurry with a mass concentration of 1% was centrifuged for 8 minutes at a relative centrifugal force of 3170g, the absorbance of the supernatant was 0.127, and the slurry had good dispersibility.

Example 2:

Mix the industrial titanium liquid and water at a volume ratio of 1:1, then add it to the condensation reflux device, and heat it under reflux at an oil bath temperature of 93°C for 8 hours. The hydrolysis system was centrifugally settled at a relative centrifugal force of 9509g for 6 minutes, the supernatant was poured off, and then 0.1mol/L dilute sulfuric acid solution was added for washing, the supernatant was removed by centrifugal sedimentation, and washed repeatedly until the washing was checked with 20% ammonium thiocyanate solution After the supernatant was colorless, it was washed with water until the pH was 5.5-7.0 to obtain metatitanic acid.

Add tartaric acid at 0.01 g/mL industrial titanium solution, degumming at 80° C. for 18 hours to obtain metatitanic acid slurry.

After finishing, be 11:100 to add the PVA solution of 5% by 5%PVA solution and metatitanic acid slurry volume ratio, then add the ethanol solution of 14% acetylacetone of metatitanic acid slurry volume (volume ratio is acetylacetone : ethanol = 1: 1), then add 5% (according to titanium mass) of N,N-dimethylamide, and stir for 5 hours to make the slurry evenly dispersed.

The hydrolysis rate of industrial titanium liquid reaches 76.58%.

Dilute the slurry with water to a mass concentration of 1%. When measuring, take 100mL of the diluted slurry, place it in a 100mL stoppered measuring cylinder, cover the stopper, and check the volume of the unclarified part after standing for seven days. The sedimentation volume reached 95mL in seven days, and the slurry had good stability.

The slurry concentration reaches 25.25% (mass percent concentration). The absorbance of the supernatant of 1% slurry was 0.048 after centrifugation at a relative centrifugal force of 3170g for 8 minutes, indicating that the slurry had good dispersibility.

Example 3:

Mix the industrial titanium liquid and water at a volume ratio of 5:1, add it to the reflux device, and heat it under reflux at an oil bath temperature of 117°C for 11 hours. The hydrolysis system was centrifugally settled at a relative centrifugal force of 9509g for 6 minutes, the supernatant was poured off, and then 0.1mol/L dilute sulfuric acid solution was added for washing, the supernatant was removed by centrifugal sedimentation, and washed repeatedly until the washing was checked with 20% ammonium thiocyanate solution After the supernatant was colorless, it was washed with water until the pH was 5.5-7.0 to obtain metatitanic acid.

Add tartaric acid at 0.064 g/mL industrial titanium solution, degumming at 40° C. for 26 hours to obtain metatitanic acid slurry.

After the end, add 5% PVA solution according to the volume ratio of 5% PVA solution and slurry at 7:25, and add 26% acetylacetone ethanol solution of the slurry volume (volume ratio is acetylacetone:ethanol=1:1) , and then add 0.5% (based on titanium mass) of N,N-dimethylamide, and stir for 5.5 hours to make the slurry uniformly dispersed.

The hydrolysis rate of industrial titanium liquid reaches 84.67%.

Dilute the slurry with water to a mass concentration of 1%. When measuring, take 100mL of the diluted slurry, place it in a 100mL stoppered measuring cylinder, cover the stopper, and check the volume of the unclarified part after standing for seven days. The sedimentation volume reached 99mL in seven days, and the slurry had good stability.

The slurry concentration reaches 47.83% (mass percent concentration). The absorbance of the supernatant of 1% slurry was 0.401 after centrifugation at a relative centrifugal force of 3170g for 8 minutes. The slurry has good dispersibility.

Example 4:

Put the industrial titanium liquid into the hydrothermal reaction kettle, and put it into the horse boiling furnace for hydrothermal hydrolysis to generate fresh metatitanic acid. The heating rate of the horse boiling furnace is 4°C/min, and the temperature is raised to 150°C and kept for 150 minutes, and immediately cooled down with flowing water. The hydrolysis system was centrifugally settled at a relative centrifugal force of 6339g for 5min, the supernatant was poured off, and the washing solution (containing 0.1mol/L sulfuric acid and 5% (mass percentage concentration) hydroxylamine hydrochloride) was added for washing, and the supernatant was removed by centrifugal sedimentation , washed repeatedly until the supernatant was colorless with 20% ammonium thiocyanate solution, and then washed with water until the pH was 5.5-7.0 to obtain metatitanic acid.

The concentration of metatitanic acid was 25%, the amount of tartaric acid added was 0.042g/mL industrial titanium solution, the concentration of tartaric acid was 21%, and the degumming was performed at 70°C for 28 hours to obtain metatitanic acid slurry.

The dosage of PVA is 0.038g/mL industrial titanium solution, the concentration of PVA solution is 1%, the mixing time of slurry is 1h, the concentration time of slurry under normal pressure at 60°C is 2.6h, and the amount of glycerin added is 14 drops/100mL industrial titanium solution.

The hydrolysis rate of industrial titanium liquid reaches 97%.

Dilute the slurry with water to a mass concentration of 1%. When measuring, take 100mL of the diluted slurry, place it in a 100mL stoppered measuring cylinder, cover the stopper, and check the volume of the unclarified part after standing for seven days. The sedimentation volume reached 96mL in seven days, and the slurry had good stability.

The mass concentration of slurry reaches 42.4% (mass percentage concentration). The absorbance of the supernatant of 1% slurry was 0.101 after centrifugation at a relative centrifugal force of 3170g for 8 minutes, indicating that the slurry has good dispersibility.

Example 5:

The industrial titanium liquid and water are mixed according to 32:9, then put into the hydrothermal reaction kettle, and put into the muffle furnace for hydrothermal hydrolysis. The heating rate is 7.6°C/min, the hydrothermal temperature is 147°C, and the hydrothermal time is 8.4h. Cool to room temperature with running water immediately after hydrothermal treatment. The hydrolysis system was centrifugally settled at a relative centrifugal force of 6339g for 5min, the supernatant was poured off, and the washing liquid (containing 0.1mol/L sulfuric acid and 10% (mass percent concentration) ascorbic acid) was added for washing, and the supernatant was removed by centrifugal sedimentation. Wash repeatedly until the washing supernatant is colorless with 20% ammonium thiocyanate solution, and then wash with water until the pH is 5.5-7.0 to obtain metatitanic acid.

The concentration of metatitanic acid was 20%, the addition amount of hydrochloric acid was 0.48g/mL industrial titanium liquid, and the degumming was carried out at 30°C for 12.5h to obtain the metatitanic acid slurry.

The amount of citric acid added is 0.15g/mL industrial titanium solution. In order to further improve the uniformity of various reagents and reduce the component segregation when the slurry is concentrated, the slurry ball milling time is 23.9h, and the amount of ethyl cellulose added is 0.128g/mL industrial For titanium liquid, the amount of terpineol is 34% of the slurry volume.

The hydrolysis rate of industrial titanium liquid reaches 95%.

Dilute the slurry to 1% mass concentration with absolute ethanol. When measuring, take 100mL of the diluted slurry and place it in a 100mL graduated cylinder with a stopper, cover the stopper, and check the volume of the unclarified part after standing for seven days. The sedimentation volume reached 100mL (ethanol system) in seven days, and the slurry had good stability.

The mass concentration of slurry reaches 21.4% (mass percentage concentration). After the 1% slurry was centrifuged for 8 minutes under a relative centrifugal force of 3170g, the absorbance of the supernatant was 0.317 (ethanol system), and the slurry had good dispersibility.

Claims (9)

1. the preparation method of slurry for dye-sensitized solar cell nanometer _TiO film photoanode, comprises the following steps: a. Heat and hydrolyze the industrial titanium liquid, centrifugally settle the hydrolysis system, remove the supernatant, and then wash the remaining part with 0.05-0.35mol/L dilute acid, centrifugally settle, remove the supernatant, and wash repeatedly until iron-free After ionization, wash with water until the pH is 5.5-7.0 to obtain metatitanic acid; b. adding a debonding agent to the metatitanic acid for degumming to obtain a metatitanic acid slurry; c. Add additives to disperse the metatitanic acid slurry evenly. 2. the nanometer TiO of dye-sensitized solar cell according to claim ₁ The preparation method of film photoanode is characterized in that: the industrial titanium liquid described in step a is the intermediate material of sulfuric acid process production titanium dioxide process . 3. The preparation method of slurry for dye-sensitized solar cell nano- _TiO2 film photoanode according to claim 1, characterized in that: the heating temperature in step a is 110-250° C., and the hydrolysis time is 1-250° C. 10h. 4 . The method for preparing the slurry for nano TiO ₂ film photoanode of dye-sensitized solar cells according to claim 1 , wherein the relative centrifugal force of the centrifugal sedimentation in step a is 2536g-9509g. 5. dye-sensitized solar cell nano TiO according to claim ₁ The preparation method of film photoanode is characterized in that: add reducing agent or complexing agent in the described dilute acid washing process of step a; The amount of reducing agent or complexing agent added is 60% to 150% based on the mass of titanium; the reducing agent is any one of hydroxylamine hydrochloride and ascorbic acid, and the complexing agent is citric acid, tartaric acid, ammonium fluoride any of the 6. the preparation method of the nano- _TiO film photoanode of dye-sensitized solar cell according to claim 1 is characterized in that: the dilute acid described in step a is dilute citric acid, dilute tartaric acid, dilute hydrochloric acid, dilute at least one of sulfuric acid. 7. dye-sensitized solar cell nano TiO according to claim ₁ The preparation method of film photoanode is characterized in that: the degumming reagent described in step b is tartaric acid, citric acid, hydrochloric acid or phosphoric acid At least one; the added amount of the degumming reagent is 0.01-0.48g/mL industrial titanium solution. 8. The preparation method of slurry for dye-sensitized solar cell nano- _TiO2 film photoanode according to claim 1, characterized in that: the temperature of degumming described in step b is 20～90°C, and the time of degumming is 4～30h. 9. The preparation method of the nano- _TiO film photoanode slurry for dye-sensitized solar cells according to claim 1, characterized in that: the additives described in step c and their addition proportions are: 400% in terms of titanium mass ～900% terpineol, 0.5%～6% ethyl cellulose, 0.005%～0.1% Triton X-100, 0.2%～1% acetylacetone, 1%～6% PEG2000, 1 At least one of %~10% hydroxyethyl cellulose, 0.5%~2% PVA, 0.1%~1% acetylacetone, 0.02%~0.15% OP emulsifier, 0.1%~0.5% humectant A kind; Wherein, humectant is any one in polyethylene glycol, butylene glycol, sorbitol, glycerin, propylene glycol, xylitol, N,N-dimethylformamide.