CN110970643A - High-temperature phosphoric acid fuel cell integrated membrane electrode and preparation and application thereof - Google Patents
High-temperature phosphoric acid fuel cell integrated membrane electrode and preparation and application thereof Download PDFInfo
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- H01M8/10—Fuel cells with solid electrolytes
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Abstract
The invention belongs to the field of electrochemical energy, and particularly relates to a preparation method of a high-temperature phosphoric acid fuel cell integrated membrane electrode, which comprises the following steps of firstly coating catalyst slurry on one side or two sides of a PBI/phosphoric acid doped wet membrane, and drying to obtain the high-temperature phosphoric acid fuel cell integrated membrane electrode; the catalyst slurry is a dispersion of an electrocatalyst-PTFE composite in an ethanol-phosphoric acid mixed solution. The invention improves the discharge performance of the battery; the utilization efficiency of the Pt catalyst is improved.
Description
Technical Field
The invention belongs to the field of electrochemical energy, and particularly relates to a method for improving the discharge performance and the operation stability of a high-temperature fuel cell based on phosphoric acid as electrolyte.
Background
The fuel cell is a reaction device which directly converts chemical energy in fuel and oxidant into electric energy through electrocatalysis reaction in a porous electrode, is not limited by Carnot cycle, and is a high-efficiency power generation technology. The proton exchange membrane fuel cell uses solid polymer as electrolyte, hydrogen as fuel, air or oxygen as oxidant, the reaction product is mainly water, and zero pollution can be realized. Besides the general characteristics of fuel cells (such as high energy conversion efficiency, environmental friendliness and the like), the proton exchange membrane fuel cell also has the outstanding characteristics of quick start at room temperature, no electrolyte loss, long service life, high specific power and specific energy and the like, is a novel movable power source which is universal for military and civilian, and is one of the research hotspots in recent years. Proton exchange membrane fuel cells usually use perfluorosulfonic acid proton exchange membranes (such as Nafion membrane series produced by dupont) as electrolyte membranes, and liquid water is required to be used as a proton conduction medium when the electrolyte membranes actually work, so the actual working temperature of the fuel cells generally needs to be lower than 100 ℃, otherwise, the water loss in the membranes can cause the rapid reduction of proton conduction capability, and the performance of the cells can rapidly decline. The low-temperature operation makes Nafion-based proton exchange membrane fuel cells face a lot of scientific and technical challenges, such as the need of reforming and purifying fuel to greatly reduce the content of CO, the difficulty of water heat management of gas-liquid two-phase flow, the complex structure of a cell system, and the like.
In order to solve many problems faced by low temperature proton exchange membrane fuel cells (LT-PEMFC), researchers have proposed a high temperature membrane fuel cell (HT-PEMFC) with an operating temperature in the range of 120-220 ℃ (Savinell et al, J.appl.electrochem., 1996, 26, 751-756), which can increase the working temperature of the fuel cell to 150-200 ℃, thereby not only greatly increasing the electrode reaction speed and improving the CO resistance of the Pt electrocatalyst, but also directly adopting methanol or ethanol reformed gas to replace pure hydrogen for feeding; secondly, water generated in high-temperature operation is mainly discharged in a steam form, so that the flooding phenomenon of electrodes can be effectively avoided, a hydrothermal management system is simplified, and the discharge performance and reliability of the battery are improved; thirdly, the temperature difference between the battery temperature and the environment is large, so that the waste heat utilization efficiency of the fuel battery can be greatly improved. High temperature membrane fuel cells based on phosphoric acid as the electrolyte have become an important development direction for fuel cells.
HT-PEMFC, like LT-PEMFC, typically employs a porous Gas Diffusion Electrode (GDE) as the cathode and anode, which typically comprises a carbon-based conductive support covered by a microporous layer comprising a mixture of PTFE and carbon powder, and uppermost a catalytic layer with reactive activity. HT-PEMFC generally uses a phosphoric acid-impregnated high molecular polymer having basic groups, such as polybenzimidazole PBI, as an electrolyte membrane, and a certain number of phosphoric acid molecules are bonded and adsorbed around the electrolyte membrane by means of electrostatic and hydrogen bonding between the basic groups and the phosphoric acid molecules, thereby realizing proton conduction in the electrolyte membrane. In the membrane electrode forming process, the PBI membrane soaked by phosphoric acid, the cathode GDE and the anode GDE are sequentially stacked and placed into a sandwich structure, and hot-press forming is carried out at a certain temperature and under a certain pressure. Free phosphoric acid in the PBI membrane can migrate and diffuse into the catalytic layer through the pore channel in the hot-press forming process of the membrane electrode, so that a phosphoric acid liquid membrane is formed around the nano electro-catalyst particles, an electrode reaction three-phase interface is constructed, and proton conduction in the catalytic layer is realized.
Research shows that the distribution states of the catalyst layer-electrolyte membrane interface and the two sides of the phosphoric acid interface are the key factors influencing the discharge performance and the operation life of the solid proton exchange membrane fuel cell, the interface compatibility and the stability of the catalyst layer on the surface of the gas diffusion layer in the membrane electrode prepared based on the hot pressing method and the electrolyte membrane are poor, and the stripping and falling phenomena are easy to occur in the cell operation process. In addition, in the process of preparing the phosphoric acid high-temperature fuel cell membrane electrode based on the simple hot-pressing method, the distribution state of phosphoric acid in the membrane and the catalytic layer is difficult to control.
In recent years, scientists at home and abroad propose various technical schemes for enhancing the interface compatibility of an electrolyte membrane and a catalyst layer in a membrane electrode of a proton exchange membrane fuel cell and improving the discharge performance and the operation stability of the fuel cell. The construction of an integrated membrane electrode structure is one of the effective strategies for enhancing the interface compatibility between the membrane and the catalyst layer. For example, Breitwieser and the like construct an electrolyte membrane on the surface of a catalyst layer based on an in-situ deposition film-forming technology, not only strengthens the interface compatibility of the Breitwieser and the catalyst layer, but also greatly reduces the Pt dosage (which can be as low as 0.029 mg/cm) while improving the discharge performance of the battery2) Improving the efficiency of Pt utilization (electrochem. Commun.,2015, 60, 168-171). US patent No. US4364803A constructs an integrated membrane electrode by in situ deposition of an electrocatalyst on an electrolyte membrane and applies it to the electrolytic water, chlor-alkali industry.
In the field of phosphoric acid high-temperature membrane fuel cells, because the PBI membrane is easy to generate a severe size swelling effect in a concentrated phosphoric acid solution, the in-situ deposition technology based on the conventional electrolyte membrane and an electrocatalyst is difficult to construct a stable electrode/electrolyte membrane interface. The interface strengthening of the electrolyte membrane and the catalyst layer in the high-temperature phosphoric acid fuel cell is mainly realized by improving the electrode preparation process based on the formed electrolyte membrane and the catalyst material, and the aim of improving the interface compatibility of the catalyst layer and the electrolyte membrane by regulating and controlling the distribution state of phosphoric acid in the catalyst layer and the electrolyte membrane and improving the discharge performance of the cell is achieved. For example, chinese patent No. CN106558705A discloses a membrane electrode assembly, which is assembled by pre-pickling a porous electrode without a binder, and then combining with a pickling membrane. In the method, partial phosphoric acid is introduced into the catalyst layer and the electrolyte membrane in advance, so that the distribution states of the phosphoric acid in the electrolyte membrane and the catalyst layer are regulated and controlled, and the phosphoric acid in the membrane electrode is utilized for optimal management; chinese patent No. CN 108336383a discloses that a certain amount of zirconia powder is doped in a catalyst layer during a membrane electrode preparation process, and a zirconium phosphate or zirconium hydrogen phosphate compound is generated by combining zirconia in the catalyst layer and phosphoric acid in an electrolyte membrane, so that a migration loss behavior of phosphoric acid during a battery discharge process is alleviated, but zirconia is a poor conductor of electron conduction, and the presence of zirconia in the catalyst layer may affect a discharge performance.
In summary, the LT-PEMFC can obtain the membrane electrode with an integrated structure by various in-situ technologies, but the above method/technology is not suitable for the phosphoric acid high temperature membrane fuel cell, mainly because the problems of membrane swelling deformation and electrolyte loss are caused by the use of liquid phosphoric acid electrolyte in the cell, which increases the difficulty of forming the integrated membrane electrode. Aiming at the problems, the catalyst layer is formed on the surface of the PBI membrane in situ by changing the components and the properties of the catalyst slurry, and then the catalyst layer is directly stacked with the gas diffusion layer to form the membrane electrode at a certain temperature or under a certain pressure.
Disclosure of Invention
The invention aims to provide a phosphoric acid high-temperature membrane fuel cell integrated membrane electrode structure and a preparation method thereof. The method comprises the steps of forming a catalyst layer on the surface of a PBI membrane in situ by changing the components and properties of catalyst slurry, then directly stacking the catalyst layer with a gas diffusion layer, and forming a membrane electrode at a certain temperature or under a certain pressure. Because the method can directly coat the catalytic slurry on the surface of the wet electrolyte membrane, the interface compatibility and the binding force of the electrolyte-catalyst layer can be strengthened to a certain extent, the mass transfer and charge transfer resistance in the electrode reaction process is reduced, and the discharge performance of the battery is improved; secondly, the catalyst layer is directly coated on the surface of the electrolyte membrane, so that partial catalyst can be prevented from being buried in the pore channel structure of the microporous layer, and the utilization efficiency of the Pt catalyst is improved.
A preparation method of a high-temperature fuel cell integrated membrane electrode comprises the following steps: coating catalyst slurry on one side or two sides of the PBI/phosphoric acid doped wet membrane, and drying to obtain the catalyst slurry; the catalyst slurry is a dispersion of an electrocatalyst-PTFE composite in an ethanol-phosphoric acid mixed solution.
The preparation method of the electrocatalyst-PTFE composite is a hydrothermal synthesis method.
The volume ratio of the ethanol to the phosphoric acid in the ethanol-phosphoric acid mixed solution is 10:1-20: 1; the adding amount of the electrocatalyst-PTFE compound in the ethanol-phosphoric acid mixed solution is 10-100mg per milliliter of the mixed solution.
Weighing electrocatalyst powder and PTFE emulsion, preparing an electrocatalyst-PTFE compound by a hydrothermal synthesis method, filtering and washing to form a catalyst-PTFE filter cake, wherein the water content in the filter cake is 40-70%, and dispersing the filter cake in an ethanol-phosphoric acid mixed solution to prepare catalyst slurry; the water content in the filter cake is 40-70%. The purpose of maintaining a certain water content in the filter cake in the step is to ensure the uniform distribution of the catalyst nanoparticles and the PTFE binder and to facilitate the subsequent dispersion and the formation of uniform catalyst slurry in a solvent; if the filter cake is dried excessively, the water is completely lost, which causes the PTFE to shrink intermolecularly and wrap the nano electro-catalyst particles to form lyophobic powder, thus being not beneficial to the subsequent preparation of the catalyst.
The method for coating the catalyst slurry on one side or two sides of the PBI-phosphoric acid doped membrane comprises the steps of preparing the catalyst slurry on one side or two sides of the PBI-phosphoric acid doped membrane by adopting a spraying or silk-screen printing method, drying to remove an ethanol solvent, stacking a gas diffusion layer on the outer side of a catalyst layer, and forming the membrane electrode after hot pressing.
The mass ratio of the electrocatalyst to the PTFE in the electrocatalyst-PTFE composite ranges from 1:1 to 3: 1; in the hydrothermal synthesis method, the mass ratio of the electrocatalyst to water is 1:500-1:1000, and the temperature during hydrothermal synthesis is 50-80 ℃; the PTFE emulsion contains 5-60 wt% of PTFE by mass.
The content of phosphoric acid in the PBI-phosphoric acid doped membrane is 300-500 wt%.
The drying temperature is 60-80 ℃, and the drying time is 10-24 h; the hot pressing temperature is 100-150 ℃; the hot pressing time is not less than 3min, and the pressure is not less than 2000 Pa.
The high-temperature fuel cell integrated membrane electrode prepared by the preparation method.
The high-temperature fuel cell integrated membrane electrode is applied to a high-temperature fuel cell taking phosphoric acid as electrolyte.
The technical scheme of the invention is as follows:
firstly, soaking washed and dried PBI in phosphoric acid to obtain a PBI acid membrane, and placing the PBI acid membrane in a phosphoric acid solution for later use; weighing a certain mass of electrocatalyst powder and PTFE emulsion, preparing an electrocatalyst-PTFE compound by a hydrothermal synthesis method, filtering and washing to form a catalyst-PTFE wet filter cake (the water content is not lower than 40%), preparing catalyst slurry by using an ethanol-phosphoric acid mixed solution based on the filter cake, spraying or silk-printing the catalyst slurry on two sides of a PBI acid membrane, and directly forming a catalyst layer on two sides of the PBI acid membrane in situ; the PBI-catalyst layer composite structure is directly stacked with a gas diffusion layer to form a sandwich structure after being dried by a vacuum oven to remove an ethanol solvent, and a membrane electrode is formed at a certain temperature or under a certain pressure.
The preparation method of the electrocatalyst slurry by the hydrothermal synthesis method of the electrocatalyst powder and the PTFE emulsion comprises the following steps:
the method comprises the following steps of dispersing a Pt/C or Pt alloy electrocatalyst and a certain amount of PTFE emulsion in a deionized water solution through ultrasonic stirring, heating, stirring, mixing, washing and filtering to form an electrocatalyst-PTFE composite filter cake;
preparing an ethanol-phosphoric acid mixed solution (the volume ratio is 10:1-20:1), and dispersing and mixing the ethanol-phosphoric acid mixed solution with an electrocatalyst-PTFE compound filter cake to form catalyst slurry for later use;
the anode electrocatalyst is a carbon-supported Pt electrocatalyst, wherein the mass ratio of Pt to the carbon support is 1: 9-9: 1;
the cathode electrocatalyst is a carbon-supported Pt and Pt multicomponent alloy electrocatalyst, wherein the mass fraction of the carbon carrier in the electrocatalysis is 10-90%; the other metal except Pt in the Pt multicomponent alloy electrocatalyst is one or more than two of Co, Ni, Ti, Cr, Sc and Mn, and the atomic molar ratio of Pt to other alloy elements is 9:1-1: 3;
the phosphoric acid content in the acid leaching membrane is not lower than 300-500 wt%, and the size swelling rate is about 150-200%;
the steps of forming the catalytic layer on the surface of the PBI acid membrane in situ are as follows:
uniformly coating the prepared catalyst slurry on the surface of a tiled acid film by using a spray gun or a screen printer, and heating by using a hot table to remove an ethanol solvent, wherein the temperature of the hot table is fixed at 60-80 ℃;
and (3) placing the PBI membrane coated with the catalytic layers on two sides in a vacuum oven for further drying to remove the ethanol solvent, wherein the drying temperature is 60-80 ℃, and the drying time is not less than 24 h.
Further, the PBI acid membrane which is dried and coated with the catalyst layers on the two sides and the two gas diffusion layers are stacked to form a sandwich structure, and the sandwich structure is pressed into a membrane electrode at a certain temperature and pressure by an oil press.
The hot pressing temperature of the oil press is 100-150 ℃; the hot pressing time is not less than 3min, and the pressure is not less than 2000 Pa.
The invention also provides a phosphoric acid high-temperature membrane fuel cell integrated membrane electrode structure prepared by the method.
Compared with the prior art, the invention has the advantages and beneficial effects that: compared with the traditional membrane electrode preparation process based on the slurry mixing-hot pressing method, the catalyst/polymer binder PTFE compound is prepared based on the hydrothermal synthesis method, the compound can realize highly uniform mixing of inorganic nano-catalyst particles and polymer binder PTFE, the agglomeration of the catalyst or the binder is avoided, the uniform mixing of the inorganic nano-catalyst particles and the polymer binder PTFE is favorable for uniform distribution of electrolyte, and the three-phase interface area of the electrode reaction is widened; secondly based on PBI/H3PO4The catalyst layer is directly prepared on the surface of the acid-soaked membrane, and the acid-soaked membrane can be soaked into the catalyst layer by using a phosphoric acid electrolyte by virtue of capillary force, so that electricity can be strengthened to a certain degreeInterface compatibility and binding force of the electrolyte-catalyst layer reduce mass transfer and charge transfer resistance in the electrode reaction process and improve the discharge performance of the battery; secondly, the catalyst layer is directly coated on the surface of the electrolyte membrane, so that the catalyst can be prevented from being buried in a pore channel structure of the microporous layer, and the utilization efficiency of the Pt catalyst is improved.
Detailed Description
Comparative example 1 construction of catalyst layer-electrolyte Membrane interface by Hot pressing method based on gas diffusion electrode
Firstly cutting a PBI membrane into 5cm by 5cm, recording the original size and the original mass of the PBI membrane, boiling the cut PBI membrane for 1h by using hot deionized water, removing organic/inorganic impurities in the membrane, and drying in a blast oven; soaking the washed and dried PBI membrane in 85 wt% phosphoric acid solution at 60-100 deg.c for 24 hr to obtain soaked PBI membrane; the acid content of the obtained PBI pickling membrane is 400 wt%, and the size swelling ratio is 200%.
Accurately weighing 100mg of electrocatalyst powder, adding 1-5ml of water to moisten the electrocatalyst powder so as to prevent the electrocatalyst powder from burning when encountering an alcohol solvent, then adding 5ml of ethanol according to the amount of adding 1ml of ethanol into every 20mg of the catalyst, carrying out ultrasonic dispersion in ice bath for 10min, adding a PTFE aqueous solution (60 wt%) to ensure that the mass ratio of PTFE to the electrocatalyst is 2:8, and continuing the ultrasonic dispersion for 10 min. Preparing slurry by respectively taking Pt/C with mass loading of 40% and PtCo/C with mass loading of 50% (Pt: Co atomic molar ratio is 3:1) as anode and cathode electrocatalysts, and depositing the slurry on a commercial gas diffusion layer SGL29BC (product of SGL company in America) by using an ultrasonic spraying method to form an anode catalytic layer and a cathode catalytic layer of a gas diffusion structure, wherein the Pt loading of the anode and the cathode are respectively 1.0mgPt/cm2And 1.5mgPt/cm2(ii) a And (3) placing the gas diffusion electrode attached with the catalytic layer in a nitrogen oven, heating to 300 ℃, and carrying out heat treatment for 60 minutes to carry out activation treatment to obtain the anode and cathode gas diffusion electrodes.
Membrane electrode preparation and single cell assembly test: placing the cathode and anode gas diffusion electrodes on two sides of PBI acid membrane pre-impregnated with phosphoric acid, respectively, and stacking to obtain a stack with effective area of 20cm2The membrane electrode is arranged in a membrane electrode hot-pressing mould, and the mould is arranged in an oil pressAnd hot-pressing for 10 minutes at 2500Pa, and cooling to room temperature to obtain the membrane electrode of the high-temperature proton membrane fuel cell.
And assembling the prepared high-temperature membrane electrode and two graphite flow field plates with serpentine flow fields into a gold-plated stainless steel polar plate with a gas inlet and a gas outlet through a sealing pad to form a single cell. The battery is heated by a heating rod, and the temperature of the battery is controlled by a thermocouple. The test conditions were: hydrogen gas was introduced into the anode at 160 ℃ under normal pressure and 0.2 liter/min, and air was introduced into the cathode at 0.8 liter/min. The measured high-temperature proton membrane fuel cell is 200mA/cm2The discharge voltage is 650mV, and the maximum power density can reach 350mW/cm2。
Example 1
Firstly cutting a PBI membrane into 5cm by 5cm, recording the original size and the original mass of the PBI membrane, boiling the cut PBI membrane for 1h by using hot deionized water, removing organic/inorganic impurities in the membrane, and drying in a blast oven; soaking the washed and dried PBI membrane in 85 wt% phosphoric acid solution at the temperature of about 80 ℃ for 24 hours to obtain an acid-soaked PBI membrane; the acid content of the obtained PBI pickling membrane is 400 wt%, and the size swelling ratio is 200%. The PBI acid membrane was tiled on the hot table surface for use.
Accurately weighing 100mg of electrocatalyst powder, adding 100ml of water, uniformly dispersing the electrocatalyst powder by ultrasonic dispersion, adding a PTFE aqueous solution (60 wt%) to enable the mass ratio of PTFE to electrocatalyst to be 2:8, raising the temperature of the solution to 60 ℃, uniformly mixing the PTFE and the electrocatalyst by mechanical stirring at a stirring speed of 500 r/min, after mechanically stirring for 2 hours, carrying out solid-liquid separation by using a filtering device to obtain a catalyst-PTFE filter cake, adding 5ml of a mixed solution of ethanol and phosphoric acid into the filter cake, and preparing catalyst slurry after ultrasonic dispersion for 10 min. The catalyst slurry of the anode and cathode respectively taking Pt/C with the mass loading of 40% and PtCo/C with the mass loading of 50% (Pt: Co atomic molar ratio is 1:1) is deposited on two sides of a PBI acid membrane which is paved on a hot bench in advance by an ultrasonic spraying method, and the temperature of the hot bench is maintained at 60 ℃. The Pt loading capacity of the anode and the cathode is respectively 0.5mgPt/cm2And 1.3mg Pt/cm2(ii) a And (3) placing the acid membrane complex attached with the catalytic layer-PBI in a vacuum oven, wherein the drying temperature is 80 ℃, and the drying time is 24 hours. After dryingThe catalyst layer-PBI acid membrane complex and two SGL29BC commercial gas diffusion layers are stacked to form a sandwich structure, and are pressed into a membrane electrode at a certain temperature and pressure by an oil press, wherein the hot pressing temperature is 100 ℃, the hot pressing time is 3min, and the pressure is 2000 Pa.
And assembling the prepared high-temperature membrane electrode and two graphite flow field plates with serpentine flow fields into a gold-plated stainless steel polar plate with a gas inlet and a gas outlet through a sealing pad to form a single cell. The battery is heated by a heating rod, and the temperature of the battery is controlled by a thermocouple. The test conditions were: hydrogen gas was introduced into the anode at 160 ℃ under normal pressure and 0.2 liter/min, and air was introduced into the cathode at 0.8 liter/min. The measured high-temperature proton membrane fuel cell is 200mA/cm2The discharge voltage is 700mV, and the maximum power density can reach 400mW/cm2。
Example 2
Firstly, cutting a PBI film into a certain size, recording the original size and the original quality of the PBI film, washing and removing impurities, and drying in a blast oven; soaking the washed and dried PBI membrane in 85 wt% phosphoric acid solution at the temperature of about 80 ℃ for 24 hours to obtain an acid-soaked PBI membrane; the acid content of the obtained PBI pickling membrane is 380 wt%, and the size swelling ratio is 180%. The PBI acid membrane was tiled on the hot table surface for use.
Accurately weighing 100mg of electrocatalyst powder, adding 100ml of water, uniformly dispersing the electrocatalyst powder by ultrasonic dispersion, adding a PTFE aqueous solution (60 wt%), enabling the mass ratio of PTFE to electrocatalyst to be 1:9, raising the temperature of the solution to 80 ℃, uniformly mixing the PTFE and the electrocatalyst by mechanical stirring at a stirring speed of 700 r/min, after mechanically stirring for 2 hours, carrying out solid-liquid separation by using a filtering device to obtain a catalyst-PTFE filter cake, adding 5ml of a mixed solution of ethanol and phosphoric acid into the filter cake, and preparing catalyst slurry after ultrasonic dispersion for 10 min. The catalyst slurry of the anode and cathode respectively taking Pt/C with the mass loading of 80% and PtCo/C with the mass loading of 70% (Pt: Co atomic molar ratio is 1:1) is deposited on two sides of a PBI acid membrane which is paved on a hot platform in advance by an ultrasonic spraying method, and the temperature of the hot platform is maintained at 80 ℃. The Pt loading capacity of the anode and the cathode is respectively 0.7mgPt/cm2And 1.5mgPt/cm2(ii) a The acid membrane complex attached with the catalytic layer-PBI is placed in a vacuum oven,the drying temperature is 80 ℃ and the time is 36 h. And stacking the dried catalyst layer-PBI acid membrane complex and two SGL29BC commercial gas diffusion layers into a sandwich structure, and pressing the sandwich structure into a membrane electrode at a certain temperature and pressure by an oil press, wherein the hot pressing temperature is 80 ℃, the hot pressing time is 3min, and the pressure is 2000 Pa.
And assembling the prepared high-temperature membrane electrode and two graphite flow field plates with serpentine flow fields into a gold-plated stainless steel polar plate with a gas inlet and a gas outlet through a sealing pad to form a single cell. The battery is heated by a heating rod, and the temperature of the battery is controlled by a thermocouple. The test conditions were: hydrogen gas was introduced into the anode at 170 ℃ and 0.2 liter/min under normal pressure, and air was introduced into the cathode at 0.8 liter/min. The measured high-temperature proton membrane fuel cell is 200mA/cm2The discharge voltage is 720mV, and the maximum power density can reach 480mW/cm2。
Example 3
Firstly, cutting a PBI membrane into a certain size, recording the original size and the original quality of the PBI membrane, boiling the cut PBI membrane for 1h by using hot deionized water, removing organic/inorganic impurities in the membrane, and drying in a blast oven; soaking the washed and dried PBI membrane in 85 wt% phosphoric acid solution at 60 ℃ for 24 hours to obtain an acid-soaked PBI membrane; the acid content of the obtained PBI pickling membrane is 450 wt%, and the size swelling ratio is 200%. The PBI acid membrane was tiled on the hot table surface for use.
Accurately weighing 100mg of electrocatalyst powder, adding 100ml of water, uniformly dispersing the electrocatalyst powder by ultrasonic dispersion, adding a PTFE aqueous solution (60 wt%), enabling the mass ratio of PTFE to electrocatalyst to be 1:9, raising the temperature of the solution to 80 ℃, uniformly mixing the PTFE and the electrocatalyst by mechanical stirring at a stirring speed of 800 r/min, mechanically stirring for 2 hours, performing solid-liquid separation by using a filtering device to obtain a catalyst-PTFE filter cake, adding 5ml of a mixed solution of ethanol and phosphoric acid into the filter cake, and preparing catalyst slurry after ultrasonic dispersion for 10 min. Catalyst slurry with 70% of Pt/C and 50% of PtMnCo/C (Pt: Mn: Co atomic molar ratio is 3:0.5:0.5) as anode and cathode respectively is deposited on two sides of a PBI acid film which is paved on a hot bench in advance by an ultrasonic spraying method, and the temperature of the hot bench is maintained at 80 ℃.The Pt loading capacity of the anode and the cathode is respectively 0.6mgPt/cm2And 1.3mgPt/cm2(ii) a And (3) placing the acid membrane complex attached with the catalytic layer-PBI in a vacuum oven, wherein the drying temperature is 60 ℃ and the drying time is 30 hours. And stacking the dried catalyst layer-PBI acid membrane complex and two SGL29BC commercial gas diffusion layers into a sandwich structure, and pressing the sandwich structure into a membrane electrode at a certain temperature and pressure by an oil press, wherein the hot pressing temperature is 80 ℃, the hot pressing time is 3min, and the pressure is 2000 Pa.
And assembling the prepared high-temperature membrane electrode and two graphite plates with serpentine flow fields into a gold-plated stainless steel polar plate with a gas inlet and a gas outlet through a sealing pad to form a single cell. The battery is heated by a heating rod, and the temperature of the battery is controlled by a thermocouple. The test conditions were: hydrogen gas was introduced into the anode at 180 ℃ under normal pressure, and air was introduced into the cathode at 0.2 liter/min. The measured high-temperature proton membrane fuel cell is 200mA/cm2The discharge voltage is 740mV, and the maximum power density can reach 550mW/cm2。
Example 4
Firstly, cutting a PBI membrane into a certain size, recording the original size and the original quality of the PBI membrane, boiling the cut PBI membrane for 1h by using hot deionized water, removing organic/inorganic impurities in the membrane, and drying in a blast oven; soaking the washed and dried PBI membrane in 85 wt% phosphoric acid solution at the temperature of about 80 ℃ for 24 hours to obtain an acid-soaked PBI membrane; the acid content of the obtained PBI pickling membrane is 450 wt%, and the size swelling ratio is 200%. The PBI acid membrane was tiled on the hot table surface for use.
Accurately weighing 100mg of electrocatalyst powder, adding 100ml of water, uniformly dispersing the electrocatalyst powder by ultrasonic dispersion, adding a PTFE aqueous solution (60 wt%), enabling the mass ratio of PTFE to electrocatalyst to be 1:9, raising the temperature of the solution to 80 ℃, uniformly mixing the PTFE and the electrocatalyst by mechanical stirring at a stirring speed of 800 r/min, mechanically stirring for 2 hours, performing solid-liquid separation by using a filtering device to obtain a catalyst-PTFE filter cake, adding 5ml of a mixed solution of ethanol and phosphoric acid into the filter cake, and preparing catalyst slurry after ultrasonic dispersion for 10 min. Respectively taking 50% of Pt/C and 50% of PtNiCo/C (Pt: Mn: Co atom mol ratio is 6:0.5:0.5) as positive ions,The cathode catalyst slurry was deposited by ultrasonic spray on both sides of a PBI acid membrane previously laid down on a hot stage maintained at 80 ℃. The Pt loading capacity of the anode and the cathode is respectively 0.6mgPt/cm2And 1.3mgPt/cm2(ii) a And (3) placing the acid membrane complex attached with the catalytic layer-PBI in a vacuum oven, wherein the drying temperature is 60 ℃ and the drying time is 30 hours. And stacking the dried catalyst layer-PBI acid membrane complex and two SGL29BC commercial gas diffusion layers into a sandwich structure, and pressing the sandwich structure into a membrane electrode at a certain temperature and pressure by an oil press, wherein the hot pressing temperature is 80 ℃, the hot pressing time is 3min, and the pressure is 2000 Pa.
And assembling the prepared high-temperature membrane electrode and two graphite plates with serpentine flow fields into a gold-plated stainless steel polar plate with a gas inlet and a gas outlet through a sealing pad to form a single cell. The battery is heated by a heating rod, and the temperature of the battery is controlled by a thermocouple. The test conditions were: hydrogen gas was introduced into the anode at 180 ℃ under normal pressure, and air was introduced into the cathode at 0.2 liter/min. The measured high-temperature proton membrane fuel cell is 200mA/cm2The discharge voltage is 735mV, and the maximum power density can reach 540mW/cm2。
Claims (10)
1. A preparation method of a high-temperature phosphoric acid fuel cell integrated membrane electrode is characterized by comprising the following steps: firstly, coating catalyst slurry on one side or two sides of a PBI/phosphoric acid doped wet membrane, and drying to obtain the catalyst slurry; the catalyst slurry is a dispersion of an electrocatalyst-PTFE composite in an ethanol-phosphoric acid mixed solution.
2. The method of claim 1, wherein: the preparation method of the electrocatalyst-PTFE composite is a hydrothermal synthesis method.
3. The method of claim 1, wherein: the volume ratio of the ethanol to the phosphoric acid in the ethanol-phosphoric acid mixed solution is 10:1-20: 1; the adding amount of the electrocatalyst-PTFE compound in the ethanol-phosphoric acid mixed solution is 10-100mg per milliliter of the mixed solution.
4. The method of claim 1, wherein: the preparation method of the catalyst slurry comprises the steps of weighing electrocatalyst powder and PTFE emulsion, preparing an electrocatalyst-PTFE compound through a hydrothermal synthesis method, filtering and washing to form a catalyst-PTFE wet filter cake, wherein the water content in the filter cake is 40-70%, and uniformly dispersing the wet filter cake in an ethanol-phosphoric acid mixed solution to prepare the catalyst slurry.
5. The method of claim 1, wherein: the method for coating the catalyst slurry on one side or two sides of the PBI-phosphoric acid doped wet membrane comprises the steps of preparing the catalyst slurry on one side or two sides of the PBI-phosphoric acid doped wet membrane by adopting a spraying or silk-screen printing method, drying to remove an ethanol solvent, stacking a gas diffusion layer on the outer side of a catalyst layer, and performing hot pressing to form the membrane electrode.
6. The method of claim 4, wherein: the mass ratio of the electrocatalyst to the PTFE in the electrocatalyst-PTFE composite ranges from 1:1 to 3: 1; in the hydrothermal synthesis method, the mass ratio of the electrocatalyst to water is 1:500-1:1000, and the temperature during hydrothermal synthesis is 50-80 ℃; the PTFE emulsion contains 5-60 wt% of PTFE by mass.
7. The method of claim 1, wherein: the content of phosphoric acid in the PBI-phosphoric acid doped membrane is 300-500 wt%.
8. The process according to claim 5, wherein: the drying temperature is 60-80 ℃, and the drying time is 10-24 h; the hot pressing temperature is 100-150 ℃; the hot pressing time is not less than 3min, and the pressure is not less than 2000 Pa.
9. A high-temperature fuel cell integrated membrane electrode prepared by the preparation method according to any one of claims 1 to 8.
10. Use of a high temperature fuel cell integrated membrane electrode according to claim 9 in a high temperature fuel cell using phosphoric acid as electrolyte.
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| Publication number | Priority date | Publication date | Assignee | Title |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101267041A (en) * | 2008-04-29 | 2008-09-17 | 中国科学院上海微系统与信息技术研究所 | A method for making film electrode of direct alcohol fuel battery |
| CN101462076A (en) * | 2009-01-06 | 2009-06-24 | 上海汽车工业(集团)总公司 | Novel use of hydrophobing agent/conductive carbon material composite body |
| US20120178013A1 (en) * | 2011-01-06 | 2012-07-12 | Samsung Electronics Co. Ltd. | Catalyst coated membrane for fuel cell, membrane and electrode assembly (mea) including same, method of manufacturing the mea, and fuel cell including the mea |
| CN103490079A (en) * | 2013-09-09 | 2014-01-01 | 清华大学 | Preparation method of flocculent-surface polybenzimidazole (PBI) membrane electrode |
| CN103887525A (en) * | 2012-12-21 | 2014-06-25 | 中国科学院大连化学物理研究所 | Cathode catalyst layer for high temperature fuel cells and preparation and membrane electrode thereof |
-
2018
- 2018-09-29 CN CN201811143949.1A patent/CN110970643A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101267041A (en) * | 2008-04-29 | 2008-09-17 | 中国科学院上海微系统与信息技术研究所 | A method for making film electrode of direct alcohol fuel battery |
| CN101462076A (en) * | 2009-01-06 | 2009-06-24 | 上海汽车工业(集团)总公司 | Novel use of hydrophobing agent/conductive carbon material composite body |
| US20120178013A1 (en) * | 2011-01-06 | 2012-07-12 | Samsung Electronics Co. Ltd. | Catalyst coated membrane for fuel cell, membrane and electrode assembly (mea) including same, method of manufacturing the mea, and fuel cell including the mea |
| CN103887525A (en) * | 2012-12-21 | 2014-06-25 | 中国科学院大连化学物理研究所 | Cathode catalyst layer for high temperature fuel cells and preparation and membrane electrode thereof |
| CN103490079A (en) * | 2013-09-09 | 2014-01-01 | 清华大学 | Preparation method of flocculent-surface polybenzimidazole (PBI) membrane electrode |
Non-Patent Citations (1)
| Title |
|---|
| 陈建军 等: "乙烷PBI/H3PO4质子传导膜燃料电池性能", 《无机化学学报》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115064745A (en) * | 2022-06-08 | 2022-09-16 | 南东北 | Preparation method of PBI phosphoric acid membrane electrode |
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