CN118299184B - Capacitor with polymer tantalum film and preparation process thereof - Google Patents

Abstract

The present invention discloses a capacitor with a polymer tantalum film and a preparation process thereof, and relates to the technical field of capacitors. The present invention discloses a preparation process of a capacitor with a polymer tantalum film, comprising the following steps: using tantalum powder and tantalum wire as raw materials through pressing, sintering, and energizing treatment to obtain an anode tantalum core; performing cathode treatment on the anode tantalum core to obtain a substrate; coating a graphite layer and a silver paste layer on the outer surface of the substrate in sequence, and using a lead frame to lead out positive and negative electrodes to obtain a capacitor. The present application performs cathode treatment on the anode tantalum core, first pre-treating it and then coating it multiple times, so that the cathode material layer is evenly coated in the anode sintering pores, effectively reducing Ro and Rex, and achieving the purpose of reducing ESR.

Description

A capacitor with polymer tantalum film and its preparation process

Technical Field

The present invention relates to the technical field of capacitors, and in particular to a capacitor with a polymer tantalum film and a preparation process thereof.

Background Art

With the development of electronic technology and electronic components, low power consumption and high-speed processing are the development direction of modern electronic equipment, requiring the application of a large number of high-frequency circuits in the whole machine, and putting forward higher requirements for the high-frequency performance of solid tantalum electrolytic capacitors. The increasing multifunctionality and high performance of electronic products make the internal current change very large. In order to eliminate the interference of large current changes, large-capacity low-ESR tantalum electrolytic capacitors are required; in order to suppress voltage fluctuations and high-frequency interference, large-capacity low-ESR tantalum electrolytic capacitors are also required; in order to reduce the power consumption of the whole machine, the use of low-loss, low-ESR tantalum capacitors is also necessary. Therefore, reducing the ESR of tantalum electrolytic capacitors is one of the directions that urgently need to be studied. In recent years, the conductivity of some new conductive polymer materials has reached 1-1000s/cm, which is much greater than the 0.1s/cm of manganese dioxide. By using a new type of high-conductivity conductive polymer material to replace manganese dioxide as the cathode of the chip tantalum electrolytic capacitor, the equivalent series resistance of the manufactured tantalum electrolytic capacitor is greatly reduced, which can not only improve the impedance-frequency characteristics of the tantalum electrolytic capacitor and its high-frequency performance, but also make it have the characteristics of high reliability and long life. It can be widely used in automatic control devices, electronic computers, military communications and other electronic circuits to meet the increasingly high-frequency requirements of tantalum electrolytic capacitors in these fields.

However, since the chip tantalum electrolytic capacitor adopts a porous sintering structure, it is difficult for the polymer cathode material to effectively enter the porous structure and coat the dielectric oxide film, which makes it impossible to achieve a good lead-out of the capacitor capacity and greatly affects other electrical parameters. In addition, the polymerization process of the conductive polymer solution system is difficult to control. Too fast a polymerization rate will form larger polymer aggregates that block the pores of the capacitor core, while too slow a polymerization rate will make it impossible for the polymer electrolyte to be effectively filled.

Summary of the invention

The purpose of the present invention is to provide a capacitor with a polymer tantalum film and a preparation process thereof, so as to solve the following technical problems:

Existing chip-type tantalum electrolytic capacitors use a porous sintered structure, and it is difficult to control the polymer cathode material to be evenly coated on the surface of the dielectric layer.

The purpose of the present invention can be achieved through the following technical solutions:

A process for preparing a capacitor having a polymer tantalum film comprises the following steps:

S1: Using tantalum powder and tantalum wire as raw materials, through pressing, sintering and energy treatment, an anode tantalum core with a dielectric layer on the surface is obtained;

S2: performing cathode treatment on the anode tantalum core to obtain a cathode-coated anode tantalum core material as a substrate;

S3: A graphite layer and a silver paste layer are sequentially coated on the outer surface of the substrate, and a lead frame is used to lead out the positive and negative electrodes to obtain a capacitor.

As a further solution of the present invention: the specific steps of cathode treatment are:

S21: immersing the anode tantalum core in a pretreatment solution and drying the pretreatment core to obtain a pretreatment core;

S22: immersing the pre-treated core in the polymer solution component 1, treating and drying, and circulating the treatment for 5-10 times to obtain a primary treated core;

S23: immersing the reprocessed core in the polymer solution component 2 for treatment and then drying, and the treatment is circulated for 3-5 times to obtain a reprocessed core;

S23: Immerse the reprocessed core in the polymer solution component three for treatment and then dry, and cycle the treatment 2-3 times to obtain a matrix.

As a further solution of the present invention: the specific steps of immersing the anode tantalum core in the pretreatment solution and then drying are: immersing for 10-15 minutes, 50-80° C., and drying for 10-15 minutes.

As a further solution of the present invention: the pretreatment liquid is obtained by mixing an activator and ethanol in a volume ratio of 1:5; the preparation method of the activator comprises the following steps:

A1: In a nitrogen atmosphere, 3,4-dimethoxythiophene, 3-chloro-1,2-propylene glycol component 1, toluene, and p-toluenesulfonic acid monohydrate are added to a reaction kettle, the temperature is controlled at 90-100°C, and the reaction is kept warm for 12-24 hours. 3-chloro-1,2-propylene glycol component 2 is added, the temperature is controlled at 90-100°C, and the reaction is kept warm for 3-6 hours. The mixture is washed with potassium hydroxide aqueous solution and saturated brine in sequence, dried with anhydrous magnesium sulfate, and the toluene is removed by rotary evaporation to obtain component 1;

A2: Add component 1, potassium thioacetate and N,N-dimethylformamide into a reaction kettle, control the temperature to 50-60°C, keep the reaction warm for 9-15 hours under stirring, extract with dichloromethane, dry the organic phase with anhydrous magnesium sulfate, and remove dichloromethane by rotary evaporation to obtain component 2;

A3: Add component 2, sodium methoxide solution and tetrahydrofuran into a reaction kettle and disperse them evenly. React at room temperature for 3-6 hours. Add hydrochloric acid aqueous solution and dichloromethane for extraction and wash with water. Take the organic phase and dry it with anhydrous magnesium sulfate. Remove dichloromethane by rotary evaporation to obtain an activator.

As a further embodiment of the present invention: in A1, the addition ratio of 3,4-dimethoxythiophene, 3-chloro-1,2-propylene glycol component one, toluene, p-toluenesulfonic acid monohydrate, and 3-chloro-1,2-propylene glycol component two is 1 g: 1-2 g: 15-30 mL: 0.08-0.15 g: 1.5-3 g.

As a further solution of the present invention: the addition ratio of component 1, potassium thioacetate and N,N-dimethylformamide in A2 is 1g:0.8-1.5g:10-50mL.

As a further solution of the present invention: the sodium methoxide solution in A3 is a 1-1.5 mol/L sodium methoxide methanol solution; the addition ratio of component 2, sodium methoxide solution and tetrahydrofuran is 1 g: 5-10 mL: 100-150 mL.

As a further scheme of the present invention: the polymer solution component one is obtained by mixing 3,4-ethylenedioxythiophene, methylbenzenesulfonate iron, and solvent component one, 3,4-ethylenedioxythiophene accounts for 0.5-2.5% of the total mass of the polymer solution component one, and the added mass ratio of 3,4-ethylenedioxythiophene and methylbenzenesulfonate is 1:3-5; the solvent component one is obtained by mixing anhydrous ethanol and n-butanol in a volume ratio of 1:2.

As a further solution of the present invention: the polymer solution component two is obtained by mixing 3,4-ethylenedioxythiophene, methylbenzenesulfonate iron, and solvent component two, 3,4-ethylenedioxythiophene accounts for 3-5% of the total mass of the polymer solution component two, and the added mass ratio of 3,4-ethylenedioxythiophene and methylbenzenesulfonate is 1:5-6; the solvent component two is obtained by mixing anhydrous ethanol and n-butanol in a volume ratio of 1:2.

As a further scheme of the present invention: the polymer solution component three is obtained by mixing 3,4-ethylenedioxythiophene, methylbenzenesulfonate iron, and solvent component three, 3,4-ethylenedioxythiophene accounts for 5-10% of the total mass of the polymer solution component three, and the added mass ratio of 3,4-ethylenedioxythiophene and methylbenzenesulfonate is 1:6-8; the solvent component three is obtained by mixing anhydrous ethanol and n-butanol in a volume ratio of 1:2.

As a further solution of the present invention: the method for preparing the anode tantalum core comprises the following steps:

Polyethylene glycol and camphor powder are mixed evenly at a mass ratio of 5-10:1 to obtain a binder solution; the binder solution and tantalum powder (50000-70000 uF·v/g) are mixed at a mass ratio of 1-5:100, and after the solvent evaporates, the mixture is co-pressed with tantalum wire to form an anode substrate with a density of 5.6g/ ^cm3 and a size of 2.5mm×1.5mm×1.2mm, wherein the depth of the tantalum wire inserted into the tantalum block is 1/4 of the height of the tantalum block; the mixture is then sintered at 1200-1400°C for 15-30min to form a porous body; the sintered porous body is placed in a 5-8‰ phosphoric acid aqueous solution for electrochemical deposition treatment, a 65V DC voltage, a 2-3mA/g film-forming current density, and a constant pressure of 3h are applied to obtain a tantalum pentoxide dielectric film, which provides an insulating dielectric layer for a tantalum electrolytic capacitor, and an anode tantalum core is obtained.

A capacitor with a polymer tantalum film is made by any one of the above preparation methods.

Beneficial effects of the present invention:

The present application uses an activator to pretreat the surface of the dielectric layer, effectively solving the problem that the dielectric layer is a Ta ₂ O ₅ inorganic material layer with high surface energy, which causes the conductive cathode layer to be unable to firmly adhere to the surface of the dielectric layer, and realizes the effective attachment of the polymer on the surface of the porous anode body. The present application uses the conductive cathode layer for multiple coatings, controls the solvent content, the ratio of monomer to oxidant, obtains a controllable polymerization solution and realizes good coating of the porous structure. One end of the activator prepared in the present application is similar to the structure of the monomer 3,4-vinyldioxythiophene for preparing the conductive polymer, and 3,4-vinyldioxythiophene is used to polymerize on the surface of the dielectric layer treated with the activator. The present application uses a higher solvent content in the early stage, and the ratio of monomer to oxidant is higher. During the later film coating period, the ratio of monomer to oxidant is appropriately reduced, so that the PEDOT layer is completely coated inside the porous anode body. The preparation method of the present application enables the subsequent cathode material layer to be evenly coated in the anode sintering pores, effectively reducing Ro; at the same time, the dense and uniform cathode layer can also reduce the contact resistance between layers, thereby reducing Rex and achieving the purpose of reducing ESR.

DETAILED DESCRIPTION

The following will be described clearly and completely in conjunction with the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Example 1 The preparation method of the activator comprises the following steps:

A1: In a nitrogen atmosphere, 10 g of 3,4-dimethoxythiophene, 10 g of 3-chloro-1,2-propylene glycol, 150 mL of toluene, and 0.8 g of p-toluenesulfonic acid monohydrate were added to a reaction kettle, the temperature was controlled at 90°C, and the reaction was kept warm for 12 h. 15 g of 3-chloro-1,2-propylene glycol was added, the temperature was controlled at 90°C, and the reaction was kept warm for 3 h. The mixture was washed with 2 mol/L potassium hydroxide aqueous solution and saturated brine in sequence, dried with anhydrous magnesium sulfate, and the toluene was removed by rotary evaporation to obtain component 1;

A2: Add 10g of component 1, 8g of potassium thioacetate and 100mL of N,N-dimethylformamide into a reaction kettle, control the temperature to 50°C, keep the reaction warm for 9h under stirring, extract with dichloromethane, take the organic phase and dry it with anhydrous magnesium sulfate, and remove dichloromethane by rotary evaporation to obtain component 2;

A3: Add 10g of component 2, 50mL of sodium methoxide solution and 1000mL of tetrahydrofuran into a reaction kettle and disperse them evenly. React at room temperature for 3h, add 5mol/L hydrochloric acid aqueous solution and dichloromethane for extraction and washing with water. Take the organic phase and dry it with anhydrous magnesium sulfate, and remove dichloromethane by rotary evaporation to obtain an activator.

Example 2 The preparation method of the activator comprises the following steps:

A1: In a nitrogen atmosphere, 10 g of 3,4-dimethoxythiophene, 15 g of 3-chloro-1,2-propylene glycol, 220 mL of toluene, and 1.2 g of p-toluenesulfonic acid monohydrate were added to a reaction kettle, the temperature was controlled at 95°C, and the reaction was kept warm for 18 h. 22 g of 3-chloro-1,2-propylene glycol was added, the temperature was controlled at 90-100°C, and the reaction was kept warm for 3-6 h. The mixture was washed with 2 mol/L potassium hydroxide aqueous solution and saturated brine in sequence, dried with anhydrous magnesium sulfate, and the toluene was removed by rotary evaporation to obtain component 1;

A2: Add 10g of component 1, 12g of potassium thioacetate and 300mL of N,N-dimethylformamide into a reaction kettle, control the temperature to 55°C, keep the reaction under stirring for 12h, extract with dichloromethane, take the organic phase and dry it with anhydrous magnesium sulfate, and remove dichloromethane by rotary evaporation to obtain component 2;

A3: Add 10g of component 2, 70mL of sodium methoxide solution and 1200mL of tetrahydrofuran into a reaction kettle and disperse them evenly. React at room temperature for 3h, add 5mol/L hydrochloric acid aqueous solution, extract with dichloromethane, wash with water, take the organic phase, dry it with anhydrous magnesium sulfate, and remove dichloromethane by rotary evaporation to obtain an activator.

Example 3 The preparation method of the activator comprises the following steps:

A1: In a nitrogen atmosphere, 10 g of 3,4-dimethoxythiophene, 20 g of 3-chloro-1,2-propylene glycol, 300 mL of toluene, and 1.5 g of p-toluenesulfonic acid monohydrate were added to a reaction kettle, the temperature was controlled at 100°C, and the reaction was kept warm for 24 h. 30 g of 3-chloro-1,2-propylene glycol was added, the temperature was controlled at 100°C, and the reaction was kept warm for 6 h. The mixture was washed with 2 mol/L potassium hydroxide aqueous solution and saturated brine in sequence, dried with anhydrous magnesium sulfate, and the toluene was removed by rotary evaporation to obtain component 1;

A2: 10 g of component 1, 15 g of potassium thioacetate, and 500 mL of N,N-dimethylformamide were added to a reaction kettle, the temperature was controlled at 60°C, and the mixture was stirred for 15 h. The mixture was extracted with dichloromethane, the organic phase was dried over anhydrous magnesium sulfate, and dichloromethane was removed by rotary evaporation to obtain component 2.

A3: Add 10g of component 2, 100mL of sodium methoxide solution and 1500mL of tetrahydrofuran into a reaction kettle and disperse them evenly. React at room temperature for 6h, add 5mol/L hydrochloric acid aqueous solution and dichloromethane for extraction and washing with water. Take the organic phase and dry it with anhydrous magnesium sulfate, and remove dichloromethane by rotary evaporation to obtain an activator.

Example 4 A process for preparing a capacitor having a polymer tantalum film comprises the following steps:

S1: Polyethylene glycol and camphor powder are mixed evenly at a mass ratio of 10:1 to obtain a binder solution; the binder solution and tantalum powder (50000uF·v/g) are mixed at a mass ratio of 5:100, and after the solvent evaporates, the mixture is co-pressed with tantalum wire to form an anode substrate with a density of 5.6g/ ^cm3 and a size of 2.5mm×1.5mm×1.2mm, and the depth of the tantalum wire inserted into the tantalum block is 1/4 of the height of the tantalum block; the mixture is then sintered at 1200-1400℃ for 15-30min to form a porous body; the sintered porous body is placed in a 5‰ phosphoric acid aqueous solution for electrochemical deposition treatment, a 65V DC voltage, a 2mA/g film-forming current density, and a constant pressure of 3h are applied to obtain a tantalum pentoxide dielectric film, which provides an insulating dielectric layer for the tantalum electrolytic capacitor to obtain an anode tantalum core;

S21: mixing the activator prepared in Example 1 with ethanol in a volume ratio of 1:5 to obtain a pretreatment solution; immersing the anode tantalum core in the pretreatment solution for 115 minutes, at 80° C., and drying for 10 minutes to obtain a pretreatment core;

S22: 2.5 g of 3,4-ethylenedioxythiophene, 12.5 g of ferric toluenesulfonate, and 85 g of a solvent obtained by mixing anhydrous ethanol and n-butanol in a volume ratio of 1:2 to obtain a polymer solution component 1; immersing the pretreated core in the polymer solution component 1, treating it, and then drying it, and the treatment is circulated 10 times to obtain a primary treatment core;

S23: 5 g of 3,4-ethylenedioxythiophene, 30 g of ferric toluenesulfonate, and 65 g of a solvent obtained by mixing anhydrous ethanol and n-butanol in a volume ratio of 1:2 to obtain a polymer solution component 2; immersing the reprocessed core in the polymer solution component 2 for treatment and then drying, and the treatment is repeated 3 times to obtain a reprocessed core;

S24: 6 g of 3,4-ethylenedioxythiophene, 36 g of iron toluenesulfonate, and 58 g of anhydrous ethanol and n-butanol in a volume ratio of 1:2 are mixed to obtain a polymer solution component three; the reprocessed core is immersed in the polymer solution component three, treated, and then dried, and the treatment is repeated twice to obtain a matrix.

S3: A graphite layer and a silver paste layer are sequentially coated on the outer surface of the substrate, and a lead frame is used to lead out the positive and negative electrodes to obtain a capacitor.

Example 5

Compared with Example 4, Example 5 only replaces the activator prepared in Example 1 used in Example 4 with an equal amount of the activator prepared in Example 2, and the remaining components and preparation method are completely consistent with Example 4.

Example 6

Compared with Example 4, Example 6 only replaces the activator prepared in Example 1 used in Example 4 with an equal amount of the activator prepared in Example 3, and the remaining components and preparation method are completely consistent with Example 4.

Comparative Example 1 A process for preparing a capacitor having a polymer tantalum film comprises the following steps:

S1: Polyethylene glycol and camphor powder are mixed evenly at a mass ratio of 10:1 to obtain a binder solution; the binder solution and tantalum powder (50000uF·v/g) are mixed at a mass ratio of 5:100, and after the solvent evaporates, the mixture is co-pressed with tantalum wire to form an anode substrate with a density of 5.6g/ ^cm3 and a size of 2.5mm×1.5mm×1.2mm, and the depth of the tantalum wire inserted into the tantalum block is 1/4 of the height of the tantalum block; the mixture is then sintered at 1200-1400℃ for 15-30min to form a porous body; the sintered porous body is placed in a 5‰ phosphoric acid aqueous solution for electrochemical deposition treatment, a 65V DC voltage, a 2mA/g film-forming current density, and a constant pressure of 3h are applied to obtain a tantalum pentoxide dielectric film, which provides an insulating dielectric layer for the tantalum electrolytic capacitor to obtain an anode tantalum core;

S21: 2.5 g of 3,4-ethylenedioxythiophene, 12.5 g of ferric toluenesulfonate, and 85 g of anhydrous ethanol and n-butanol in a volume ratio of 1:2 are mixed to obtain a polymer solution component 1; an anode tantalum core is immersed in the polymer solution component 1 for treatment and then dried, and the treatment is circulated for 10 times to obtain a primary treatment core;

S22: 5 g of 3,4-ethylenedioxythiophene, 30 g of ferric toluenesulfonate, and 65 g of anhydrous ethanol and n-butanol in a volume ratio of 1:2 are mixed to obtain a polymer solution component 2; the reprocessed core is immersed in the polymer solution component 2 for treatment and then dried, and the treatment is repeated 3 times to obtain a reprocessed core;

S23: 6 g of 3,4-ethylenedioxythiophene, 36 g of iron toluenesulfonate, and 58 g of anhydrous ethanol and n-butanol in a volume ratio of 1:2 are mixed to obtain a polymer solution component three; the reprocessed core is immersed in the polymer solution component three for treatment and then dried, and the treatment is repeated twice to obtain a substrate.

S3: A graphite layer and a silver paste layer are sequentially coated on the outer surface of the substrate, and a lead frame is used to lead out the positive and negative electrodes to obtain a capacitor.

Comparative Example 2 Compared with Example 4, in Comparative Example 2, only an equal amount of the activator prepared in Example 1 used in Example 4 is replaced by mercaptosilane coupling agent KH590, and the remaining components and preparation method are completely the same as those in Example 4.

Comparative Example 3 Compared with Example 4, in Comparative Example 2, only an equal amount of the activator prepared in Example 1 used in Example 4 is replaced by sodium dodecylbenzene sulfonate, and the remaining components and preparation method are completely the same as those in Example 4.

Performance testing:

The capacitors prepared in Examples 4-6 and Comparative Examples 1-3 were tested for leakage current I ₀ at 25° C.; the loss tangent was tested at 125° C. and the capacitor capacity was detected, and the capacity extraction rate was calculated, wherein the capacity extraction rate is the percentage of the actual capacity after coating to the measured capacity after energization; the test results are shown in Table 1;

Table 1: Statistical table of electrical performance test data of Examples 4-6 and Comparative Examples 1-3

As can be seen from Table 1, the activator prepared in the present application pre-treats the dielectric layer. During the impregnation process, the activator molecules are adsorbed on the interface in a directional arrangement, which reduces the surface tension of the dielectric layer and allows the subsequent cathode film layer to be evenly and densely attached to the surface of the dielectric layer in the micropores; not only can the cathode layer and the dielectric layer be closely adsorbed on the activator thin layer, greatly improving the material capacity extraction rate; but also, the activator thin layer plays a good role as an intermediate transition layer, and the loss and ESR after the film are small.

The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims (5)

1. A process for preparing a capacitor having a polymer tantalum film, characterized in that it comprises the following steps: S1: Using tantalum powder and tantalum wire as raw materials, through pressing, sintering and energy treatment, an anode tantalum core with a dielectric layer on the surface is obtained; S2: performing cathode treatment on the anode tantalum core to obtain a cathode-coated anode tantalum core material as a substrate; S3: coating a graphite layer and a silver paste layer on the outer surface of the substrate in sequence, and using a lead frame to lead out the positive and negative electrodes to obtain a capacitor; The specific steps of the cathode treatment are: S21: immersing the anode tantalum core in a pretreatment solution and drying the pretreatment core to obtain a pretreatment core; S22: immersing the pre-treated core in the polymer solution component 1, treating and drying, and circulating the treatment for 5-10 times to obtain a primary treated core; S23: immersing the reprocessed core in the polymer solution component 2 for treatment and then drying, and the treatment is circulated for 3-5 times to obtain a reprocessed core; S24: immersing the reprocessed core in the polymer solution component 3 for treatment and then drying, and the treatment is circulated 2-3 times to obtain a matrix; The pretreatment liquid is obtained by mixing an activator and ethanol in a volume ratio of 1:5; the preparation method of the activator comprises the following steps: A1: In a nitrogen atmosphere, 3,4-dimethoxythiophene, 3-chloro-1,2-propylene glycol component 1, toluene, and p-toluenesulfonic acid monohydrate are added to a reaction kettle, the temperature is controlled at 90-100°C, and the reaction is kept warm for 12-24 hours. 3-chloro-1,2-propylene glycol component 2 is added, the temperature is controlled at 90-100°C, and the reaction is kept warm for 3-6 hours. The mixture is washed with potassium hydroxide aqueous solution and saturated brine in sequence, dried with anhydrous magnesium sulfate, and the toluene is removed by rotary evaporation to obtain component 1; A2: Add component 1, potassium thioacetate and N,N-dimethylformamide into a reaction kettle, control the temperature to 50-60°C, keep the reaction warm for 9-15 hours under stirring, extract with dichloromethane, dry the organic phase with anhydrous magnesium sulfate, and remove dichloromethane by rotary evaporation to obtain component 2; A3: Add component 2, sodium methoxide solution and tetrahydrofuran into a reaction kettle and disperse them evenly. React at room temperature for 3-6 hours. Add hydrochloric acid aqueous solution and dichloromethane for extraction and wash with water. Take the organic phase and dry it with anhydrous magnesium sulfate. Rotary evaporate to remove dichloromethane to obtain an activator. The polymer solution component one is obtained by mixing 3,4-ethylenedioxythiophene, methylbenzenesulfonate iron, and solvent component one, wherein 3,4-ethylenedioxythiophene accounts for 0.5-2.5% of the total mass of the polymer solution component one, and the addition mass ratio of 3,4-ethylenedioxythiophene and methylbenzenesulfonate iron is 1:3-5; the solvent component one is obtained by mixing anhydrous ethanol and n-butanol in a volume ratio of 1:2; The polymer solution component 2 is obtained by mixing 3,4-ethylenedioxythiophene, methylbenzenesulfonate iron, and solvent component 2, wherein 3,4-ethylenedioxythiophene accounts for 3-5% of the total mass of the polymer solution component 2, and the addition mass ratio of 3,4-ethylenedioxythiophene and methylbenzenesulfonate iron is 1:5-6; the solvent component 2 is obtained by mixing anhydrous ethanol and n-butanol in a volume ratio of 1:2; The polymer solution component three is obtained by mixing 3,4-ethylenedioxythiophene, ferric toluenesulfonate, and solvent component three, wherein 3,4-ethylenedioxythiophene accounts for 5-10% of the total mass of the polymer solution component three, and the added mass ratio of 3,4-ethylenedioxythiophene and ferric toluenesulfonate is 1:6-8; the solvent component three is obtained by mixing anhydrous ethanol and n-butanol in a volume ratio of 1:2. 2. A process for preparing a capacitor with a polymer tantalum film according to claim 1, characterized in that the addition ratio of 3,4-dimethoxythiophene, 3-chloro-1,2-propylene glycol component one, toluene, p-toluenesulfonic acid monohydrate, and 3-chloro-1,2-propylene glycol component two in A1 is 1g: 1-2g: 15-30mL: 0.08-0.15g: 1.5-3g. 3. The process for preparing a capacitor with a polymer tantalum film according to claim 1, characterized in that the addition ratio of component 1, potassium thioacetate, and N,N-dimethylformamide in A2 is 1g:0.8-1.5g:10-50mL. 4. A process for preparing a capacitor with a polymer tantalum film according to claim 1, characterized in that the sodium methoxide solution in A3 is a 1-1.5 mol/L sodium methoxide methanol solution; and the addition ratio of component 2, sodium methoxide solution, and tetrahydrofuran is 1 g: 5-10 mL: 100-150 mL. 5. A capacitor with a polymer tantalum film, characterized in that it is made by the preparation method described in any one of claims 1 to 4.