A full high-entropy proton ceramic fuel cell and its preparation method

Abstract

The present invention discloses a full high-entropy proton ceramic fuel cell and a preparation method thereof. The fuel cell in the present invention includes a cathode, an electrolyte and an anode; wherein, both the cathode material and the electrolyte material are high-entropy perovskites; the anode material includes NiO and high-entropy perovskite. In the present invention, a single-phase ABO3-type high-entropy perovskite is selected as the cathode material, the electrolyte material and the anode material. The finally formed full high-entropy proton ceramic fuel cell not only has good flexural strength, but also has the characteristics of high power density, small resistance and output stability.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cells, and particularly relates to a full high-entropy proton ceramic fuel cell and a preparation method thereof. Background Art

[0002] A proton ceramic fuel cell (PCFC) is a solid oxide fuel cell that uses a proton conductor as an electrolyte. Due to the lower activation energy of proton transport, compared with traditional oxygen ion-conducting solid oxide fuel cells (O-SOFCs), PCFCs have higher energy conversion efficiency, and the operating temperature can be reduced to below 650 °C, which is beneficial to reducing the difficulty of stacking single cells, shortening the start-up time of the battery, and increasing the service life of the battery. Therefore, in recent years, PC-SOFCs (proton-conducting solid oxide fuel cells) have received intense attention in the field of energy conversion. However, at present, PCFCs have problems such as cumbersome preparation processes, large interfacial resistance, poor mechanical strength, and poor stability, resulting in a slow progress in the commercial development of PCFCs. Summary of the Invention

[0003] In order to solve the problems of cumbersome processes, large interfacial resistance, poor mechanical strength, and poor stability existing in existing PCFCs, one of the objectives of the present invention is to provide a full high-entropy proton ceramic fuel cell.

[0004] The technical solution of the present invention for solving the above technical problems is as follows:

[0005] A full high-entropy proton ceramic fuel cell includes a cathode, an electrolyte, and an anode; wherein, both the cathode material and the electrolyte material are high-entropy perovskites; the anode material includes NiO and high-entropy perovskite.

[0006] The beneficial effect of the present invention is that: in the present invention, a single-phase ABO 3 type high-entropy perovskite is selected as the composition of the cathode material, electrolyte material, and anode material, and the finally formed full high-entropy proton ceramic fuel cell not only has good flexural strength, but also has high power density and output stability.

[0007] On the basis of the above technical solution, the present invention can also be improved as follows:

[0008] Further, the cathode material is a high-entropy perovskite with a chemical general formula of LnXnO 3-δ , wherein, Ln is at least one of Ba, Gd, Ca, Sr, and La, and Xn is composed of any three elements among Co, Fe, and Zr, Sn, Pr, Nb, Mo, Mn, Ni, Cu, and Zn and the constituent elements have an equal atomic ratio.

[0009] Further, the cathode material is BaCo 0.2 Fe 0.2Zr 0.2 Sn 0.2 Pr 0.2 O 3-δ 。

[0010] Furthermore, the electrolyte material is a high-entropy perovskite with a chemical general formula of BaYnO 3-δ , where Yn is composed of any three elements selected from Zr, Ce, Sn, Ti, Y, Nb, Mo, Mn, Ni, Cu, and Zn, and the constituent elements have an equal atomic ratio.

[0011] Furthermore, the electrolyte material is BaZr 0.2 Ce 0.2 Sn 0.2 Ti 0.2 Y 0.2 O 3-δ 。

[0012] Furthermore, the mass percentage of the high-entropy perovskite and NiO in the anode material is 30% - 70%; the high-entropy perovskite in the anode material is a high-entropy perovskite with a chemical general formula of BaYnO 3-δ , where Yn is composed of any three elements selected from Zr, Ce, Sn, Ti, Y, Nb, Mo, Mn, Ni, Cu, and Zn, and the constituent elements have an equal atomic ratio.

[0013] The second object of the present invention is to provide a preparation method of a full high-entropy proton ceramic fuel cell, comprising the following steps:

[0014] Step 1: First, place the anode material, electrolyte material, and cathode material in a mold in sequence, and then co-press them into a sintering precursor;

[0015] Step 2: Sinter the sintering precursor to obtain a full high-entropy proton ceramic fuel cell after sintering.

[0016] The beneficial effects of adopting the above further technical solutions are as follows:

[0017] In the present invention, a one-step co-pressing method is used to prepare a full high-entropy proton ceramic fuel cell, which simplifies the preparation process flow of the existing PCFC, and the fuel cell prepared by the one-step co-pressing method also has good mechanical strength; in addition, during the one-step co-pressing method, the cathode / electrolyte / anode are integrally formed, so that there is very good contact between the cathode and the electrolyte, which can effectively reduce the interfacial resistance of the fuel cell.

[0018] Furthermore, the mass ratio of the cathode material to the electrolyte material in Step 1 is 1:2 - 2:1; the mass ratio of the cathode material to the anode material is 1:5 - 1:10.

[0019] Further, the pressure for co - pressing in Step 1 is 18 - 25 MPa, and the time for co - pressing is 1 - 3 min.

[0020] Further, the sintering conditions in Step 2 are: the sintering temperature is 1200 - 1480 °C, and the sintering time is 8 - 12 h.

[0021] The present invention has the following beneficial effects:

[0022] 1. In the present invention, the fuel cell is a proton ceramic fuel cell with a full high - entropy structure, which has a relatively high power density and output stability. At a working temperature of 550 °C, its maximum output power can reach 0.41 W·cm -2 , and in the constant - current working mode with a current density of 0.34 A·cm -2 , the attenuation rate of the battery is 1.36×10 -4 W / kWh.

[0023] 2. In the present invention, the "anode material / electrolyte material / cathode material" is co - pressed in one step to form a sintering precursor, and then the sintering precursor is sintered to obtain a proton ceramic fuel cell with a full high - entropy structure; the one - step co - pressing method in the present invention simplifies the traditional process of preparing the anode / electrolyte support first and then coating the cathode for the proton ceramic fuel cell. Therefore, the full high - entropy proton ceramic fuel cell in the present invention has the characteristics of simple preparation process, high mechanical strength of the prepared battery, and small interfacial resistance; and through subsequent test analysis, the total impedance of the battery prepared by the one - step co - pressing method in the present invention is about 0.30 Ω·cm -2 , while the total impedance of the battery prepared by screen - printing the cathode is about 0.36 Ω·cm -2 ; the anti - bending strength of the battery prepared by the one - step co - pressing method in the present invention is about 72 ± 3.07 MPa, while the anti - bending strength of the battery prepared by screen - printing the cathode is about 66 ± 3.57 MPa. Description of the Drawings

[0024] Figure 1 XRD pattern of the BaCo 0.2 Fe 0.2 Zr 0.2 Sn 0.2 Pr 0.2 O 3-δ (BCFZSP) cathode material;

[0025] Figure 2 XRD pattern of the BaCo 0.2 Fe 0.2 Zr 0.2 Sn 0.2 Pr 0.2 O 3-δ(BCFZSP) XRD pattern of the cathode material;

[0026] Figure 3 BaZr synthesized by the solid-phase method 0.2 Ce 0.2 Sn 0.2 Ti 0.2 Y 0.2 O 3-δ (BZCSTY) XRD pattern of the electrolyte material;

[0027] Figure 4 BaZr synthesized by the sol-gel method 0.2 Ce 0.2 Sn 0.2 Ti 0.2 Y 0.2 O 3-δ (BZCSTY) XRD pattern of the electrolyte material;

[0028] Figure 5 XRD pattern of the anode material;

[0029] Figure 6 Cross-sectional SEM image of the full high-entropy proton ceramic fuel cell prepared with screen-printed cathode;

[0030] Figure 7 Discharge curve of the full high-entropy proton ceramic fuel cell prepared with screen-printed cathode;

[0031] Figure 8 Impedance plot of the full high-entropy proton ceramic fuel cell prepared with screen-printed cathode at 650 °C;

[0032] Figure 9 Long-term discharge stability plot of the full high-entropy proton ceramic fuel cell prepared with screen-printed cathode;

[0033] Figure 10 Cross-sectional SEM image of the full high-entropy proton ceramic fuel cell prepared by the one-step co-pressing method of the present invention;

[0034] Figure 11 Discharge curve of the full high-entropy proton ceramic fuel cell prepared by the one-step co-pressing method of the present invention;

[0035] Figure 12 Impedance plot of the full high-entropy proton ceramic fuel cell prepared by the one-step co-pressing method of the present invention at 650 °C;

[0036] Figure 13 Long-term discharge stability plot of the full high-entropy proton ceramic fuel cell prepared by the one-step co-pressing method of the present invention. Detailed implementation manners

[0037] The following will describe a full - entropy proton ceramic fuel cell and its preparation method in the present application in combination with embodiments. However, the present application can be exemplified in many different forms and should not be construed as limited to the specific embodiments set forth herein. Rather, these embodiments are provided so that the present application will be thorough and complete, and will fully convey the scope of the present application to those skilled in the art.

[0038] The inventors have been deeply involved in the field of proton ceramic fuel cells (PCFCs) and have conducted a detailed investigation on the anodes, cathodes, electrolytes, and preparation processes of PCFCs.

[0039] Cathode materials: Currently, the cathodes of PCFCs mainly use perovskite oxides such as La 0.8 Sr 0.2 Co 1-x Fe x O 3-δ (LSCF), Ba 0.5 Sr 0.5 Co 1- x Fe x O 3-δ (BSCF) with mixed oxygen ion - electron conduction functions as electrocatalysts. However, these perovskite materials have the following two problems in PC - SOFCs: (1) The proton conductivities of LSCF and BSCF materials are so small that they can be ignored, resulting in the cathode reaction active sites being mainly limited to the "electrolyte - cathode - air" triple - phase interface, and the poor intrinsic catalytic activity leads to limited cathode catalytic efficiency; (2) Water is generated at the PC - SOFC cathode, and the phase structures of LSCF and BSCF are unstable in a high - water - vapor - pressure atmosphere, producing insulating impurity phases and reducing the electrode stability.

[0040] Electrolyte materials: Currently, the electrolytes of PCFCs mainly consist of solid solutions composed of BaZr 0.8 Y 0.2 O 3-δ (BZY) and BaCe 0.8 Y 0.2 O 3-δ (BCY) in different proportions. However, BZY has low ionic conductivity at low temperatures and poor sinterability, and high - temperature sintering is required to obtain a dense electrolyte, increasing the preparation cost; BCY is unstable in the fuel cell operating atmosphere and easily decomposes to produce barium carbonate and barium cerate, unable to meet the requirements of long - term stability operation. In addition, the mechanical strength of this type of electrolyte is poor. Due to the large chemical environment differences on both sides of the electrolyte, there will be large stresses in the actual working conditions of the electrolyte, and the poor mechanical strength is likely to cause the electrolyte to be damaged during long - term operation, further increasing the risk of battery failure.

[0041] Anode material: Currently, the anode of PCFC is mainly composed of a composite ceramic of NiO - BZY - BCY. Usually, the anode serves as the support of the entire PCFC. Due to the poor mechanical strength of BZY - BCY, the mechanical strength of the battery support is also poor. During the reduction activation of the anode (reducing NiO to metallic Ni), large stresses will also occur inside the support, and the poor support strength will also increase the risk of battery failure.

[0042] Preparation process of PCFC: Currently, the most common method is to first prepare the anode / electrolyte half - cell by methods such as co - pressing or tape - casting, and then coat the cathode layer on the electrolyte side of the half - cell through processes such as screen printing, and then sinter to obtain a single - cell with a "anode / electrolyte / cathode" sandwich structure. The main problem of this process is that the contact between the electrolyte and the cathode is usually poor, resulting in a large interfacial polarization resistance of the battery.

[0043] Based on this, the present invention provides a full - high - entropy proton ceramic fuel cell (FH - PCFC) prepared by a one - step co - pressing method; the cathode material, electrolyte material, and anode material of the cell are all composed of ABO 3 type high - entropy perovskite oxides; among them, high - entropy oxides (HEO) are a class of functional ceramics usually composed of 5 or more elements in an equiatomic ratio or near - equiatomic ratio. HEO has a large configurational entropy and a low system free energy, so HEO usually has good stability; on the other hand, in HEO, atoms with different atomic radii and different element electronegativities occupy the same atomic sites, so HEO has a multi - component synergistic effect and often exhibits good ion - transport characteristics.

[0044] An embodiment of the first aspect of the present invention provides a full - high - entropy proton ceramic fuel cell, including a cathode, an electrolyte, and an anode; among them, the cathode material and the electrolyte material are both high - entropy perovskites; the anode material includes NiO and high - entropy perovskite.

[0045] In this embodiment, the cathode, electrolyte, and anode materials of the full - high - entropy proton ceramic fuel cell are all selected as high - entropy perovskites. Therefore, the battery in this embodiment not only has good flexural strength, but also has high power density and output stability. In addition, the cathode material of the ABO 3 type high - entropy perovskite has good ion - electron conductivity, effectively increasing the active sites of the electrode reaction, thereby improving the catalytic efficiency of the redox process and enhancing the electrochemical performance of the cathode.

[0046] In addition, when the full - high - entropy proton ceramic fuel cell in this embodiment is in use, a fuel gas needs to be introduced into the anode side; among them, the flow rate of the fuel gas is: 50 ml / min; the fuel gas is any one of hydrogen, methane, methanol, and carbon monoxide.

[0047] The working mechanism of the full high-entropy proton ceramic fuel cell in this embodiment is as follows: First, the H + ions generated at the anode are transferred through the electrolyte to the reaction active sites in contact with O 2 at the cathode of the FH-SOFC. O 2 undergoes electrochemical reduction to generate H 2 O, while releasing electrons. The metal current collector provides a transmission channel for the electrons, forming an electric current in the external circuit.

[0048] In addition, in some embodiments, the cathode material is a high-entropy perovskite with the chemical formula LnXnO 3-δ . Among them, Ln is at least one of Ba, Gd, Ca, Sr, and La, and Xn is composed of any three elements among Co, Fe, and Zr, Sn, Pr, Nb, Mo, Mn, Ni, Cu, and Zn, and the constituent elements have an equal atomic ratio; where δ is the oxygen vacancy. In this embodiment, the cathode material with the chemical formula LnXnO 3-δ has the conductive property of simultaneously transporting electrons, oxygen ions, and protons, as well as good phase structure stability, which is beneficial to improving the electrochemical activity and stability of the cathode. Preferably, the cathode material in this embodiment can be BaCo 0.2 Fe 0.2 Zr 0.2 Sn 0.2 Pr 0.2 O 3-δ . In addition, when Ln includes two or more of Ba, Gd, Ca, Sr, and La, Ln can be the doping of Gd / La at the Ba / Sr / Ca site, that is, (Ba / Sr / Ca)1-x(Gd / La)x, x = 0 to 0.2. For example, Ln can be Ba0.9Gd0.1, Sr0.8La0.2.

[0049] In addition, in some embodiments, the electrolyte material is a high-entropy perovskite with the chemical formula BaYnO 3-δ . Among them, Yn is composed of any three elements among Zr, Ce, and Sn, Ti, Y, Nb, Mo, Mn, Ni, Cu, and Zn, and the constituent elements have an equal atomic ratio. In this embodiment, the electrolyte material with the chemical formula BaYnO 3-δ has a high proton conductivity, good sintering activity, and high mechanical strength, and has good stability in high-concentration carbon dioxide, water vapor, and hydrogen atmospheres. Preferably, the electrolyte material in this embodiment can be BaZr 0.2 Ce 0.2 Sn 0.2 Ti 0.2 Y 0.2 O 3-δ .

[0050] In addition, in some embodiments, the mass percentages of the high-entropy perovskite and NiO in the anode material are 30% to 70%; preferably, the mass ratio of the high-entropy perovskite to NiO is 1:2 to 7:10, and further preferably, the mass ratio of the high-entropy perovskite to NiO is 2:3; the high-entropy perovskite in the anode material has a chemical general formula of BaYnO 3-δ The high-entropy perovskite, where Yn is composed of any three elements among Zr, Ce, and Sn, Ti, Y, Nb, Mo, Mn, Ni, Cu, and Zn and the constituent elements have an equal atomic ratio. In this embodiment, the anode material formed within this mass range has relatively high mechanical strength and good chemical stability.

[0051] In this embodiment, both the cathode material and the electrolyte material can be synthesized by the solid-phase method and the sol-gel method. Specifically:

[0052] (1) Synthesizing the cathode material by the solid-phase method, including the following steps:

[0053] After thoroughly mixing the precursors of the cathode material, sintering is carried out in an air atmosphere, and a cathode material with a chemical general formula of LnXnO 3-δ High-entropy perovskite is obtained.

[0054] Among them, the precursors must include barium carbonate, cobalt(III) oxide, and iron(III) oxide, and the precursors also include zirconium oxide, praseodymium hexadecaoxide, and tin oxide; preferably, the masses of barium carbonate, cobalt(III) oxide, iron(III) oxide, zirconium oxide, praseodymium hexadecaoxide, and tin oxide are respectively: 3.9468 g, 0.321 g, 0.3194 g, 0.4929 g, 0.6810 g, and 0.6028 g; preferably, the sintering conditions are: sintering temperature 1200 °C, sintering time 2 h. In this embodiment, the finally obtained cathode material in powder form is BaCo 0.2 Fe 0.2 Zr 0.2 Sn 0.2 Pr 0.2 O 3-δ (BCFZSP).

[0055] In addition, in the actual process, zirconium oxide, praseodymium hexadecaoxide, and tin oxide can be replaced with other substances according to the specific cathode material. In this embodiment, the precursors of the cathode material are ball-milled and mixed in a planetary ball mill, and absolute ethanol is added before the start of ball milling; among them, the ball milling time is 24 h, and the rotational speed of the ball mill is 400 r / min.

[0056] (2) Synthesizing the cathode material by the sol-gel method, including the following steps:

[0057] Dissolve the cathode material precursor, citric acid monohydrate, and ethylenediaminetetraacetic acid in deionized water to form a mixed solution; then gradually drop 25% ammonia water into the mixed solution until the mixed solution becomes clear, and heat the clear solution to form a stable gel. The formed gel is successively subjected to heat preservation and sintering to obtain a cathode material with the chemical formula LnXnO 3-δ High-entropy perovskite cathode material.

[0058] Among them, the precursor must include barium nitrate, cobalt nitrate hexahydrate, and iron nitrate nonahydrate, and the precursor also includes zirconium oxynitrate, praseodymium nitrate hexahydrate, and tin tetrachloride; preferably, the masses of barium nitrate, cobalt nitrate hexahydrate, iron nitrate nonahydrate, zirconium oxynitrate, praseodymium nitrate hexahydrate, tin tetrachloride, citric acid monohydrate, and ethylenediaminetetraacetic acid in this embodiment are: 2.6134 g, 2.9103 g, 4.04 g, 2.3123 g, 4.3501 g, 2.6052 g, 4.2028 g, and 8.7672 g respectively.

[0059] In addition, preferably, the heating temperature in this embodiment is 80 °C, the heat preservation conditions are: the heat preservation temperature is 250 °C and the heat preservation time is 2 h, and the sintering conditions are: the sintering temperature is 1200 °C and the sintering time is 2 h; the finally obtained cathode material in powder form BaCo 0.2 Fe 0.2 Zr 0.2 Sn 0.2 Pr 0.2 O 3-δ (BCFZSP). In addition, zirconium oxynitrate, praseodymium nitrate hexahydrate, and tin tetrachloride can be replaced with other substances according to the specific cathode material.

[0060] (3) Synthesis of electrolyte material by solid-phase method

[0061] The method for synthesizing the electrolyte material by the solid-phase method is the same as the method for synthesizing the cathode material by the solid-phase method in (1), except that:

[0062] After sintering, a high-entropy perovskite electrolyte material with the chemical formula BaYnO 3-δ is obtained;

[0063] The precursor must include barium carbonate, cerium oxide, and zirconium oxide, and also includes tin oxide, titanium dioxide, and yttrium oxide; preferably, the masses of barium carbonate, cerium oxide, zirconium oxide, tin oxide, titanium dioxide, and yttrium oxide in this embodiment are: 9.867 g, 1.232 g, 1.721 g, 1.507 g, 0.799 g, and 1.129 g respectively.

[0064] In this example, preferably, the sintering conditions are: the sintering temperature is 1400 °C and the sintering time is 5 h;

[0065] In this embodiment, after sintering, the finally obtained electrolyte material is in powder form, BaZr 0.2 Ce 0.2 Sn 0.2 Ti 0.2 Y 0.2 O 3-δ (BZCSTY).

[0066] In addition, tin oxide, titanium dioxide and yttrium oxide can be replaced with other substances according to the specific electrolyte material.

[0067] (4) Synthesizing the electrolyte material by sol-gel method

[0068] The method for synthesizing the electrolyte material by sol-gel method is the same as that for synthesizing the cathode material by sol-gel method in (2), the difference is that:

[0069] After sintering, an electrolyte material with a chemical general formula of BaYnO 3-δ high-entropy perovskite is obtained;

[0070] The precursor must include barium nitrate, cerium nitrate and zirconium oxynitrate, and also includes titanium tetrachloride, tin tetrachloride and yttrium nitrate; preferably, the masses of barium nitrate, cerium nitrate, zirconium oxynitrate, titanium tetrachloride, tin tetrachloride, yttrium nitrate, citric acid monohydrate and ethylenediaminetetraacetic acid in this embodiment are: 13.067 g, 2.3123 g, 3.2613 g, 1.8968 g, 2.6052 g, 2.7492 g, 4.2028 g and 8.7672 g respectively.

[0071] In this example, preferably, the sintering conditions are: the sintering temperature is 1400 °C and the sintering time is 5 h;

[0072] In this embodiment, the finally obtained electrolyte material in powder form, BaZr 0.2 Ce 0.2 Sn 0.2 Ti 0.2 Y 0.2 O 3-δ (BZCSTY).

[0073] In addition, titanium tetrachloride, tin tetrachloride and yttrium nitrate can be replaced with other substances according to the specific electrolyte material.

[0074] In this embodiment, the preparation of the anode material includes the following steps:

[0075] First, NiO is fully mixed with the electrolyte material synthesized by the above solid-phase method and the pore-forming agent in a 5% PVA aqueous solution, and the mixed substance is sintered to obtain the anode material;

[0076] Among them, the mass ratio of the electrolyte material to NiO is 1:2 to 7:10. Preferably, the mass ratio of the electrolyte to NiO is 2:3;

[0077] The mass ratio of the pore former to nickel oxide is 1:4 to 2:3. Preferably, the mass ratio of the pore former to NiO is 1:2; among them, the pore former is starch;

[0078] The sintering conditions are: the sintering temperature is 1450 °C and the sintering time is 8 h; sintering is carried out at this temperature, and NiO does not react or decompose with the electrolyte material.

[0079] An embodiment of the second aspect of the present invention provides a preparation method of a full high-entropy proton ceramic fuel cell, including the following steps:

[0080] Step 1, first place the anode material, electrolyte material and cathode material in a mold in sequence, and then co-press them into a sintering precursor;

[0081] Step 2, sinter the sintering precursor to obtain a full high-entropy proton ceramic fuel cell after sintering.

[0082] The FH-PCFC in this embodiment is prepared by one-step co-pressing and then high-temperature sintering. It has a simple preparation process; in addition, the integrated forming process enables very good contact between the cathode material / electrolyte, which can effectively reduce the interfacial polarization resistance of the battery and increase the mechanical strength of the whole battery at the same time.

[0083] In some embodiments, the mass ratio of the cathode material to the electrolyte material in Step 1 is 1:2 to 2:1; the mass ratio of the cathode material to the anode material is 1:5 to 1:10. Preferably, the mass ratio of the cathode material:electrolyte material:anode material in this embodiment is 1:1:8.

[0084] In addition, in some embodiments, the pressure of co-pressing in Step 1 is 18 to 25 MPa, and the time of co-pressing is 1 to 3 min.

[0085] In addition, in some embodiments, the sintering conditions in Step 2 are: the sintering temperature is 1200 to 1480 °C and the sintering time is 8 to 12 h.

[0086] Embodiment

[0087] Hereinafter, a full high-entropy proton ceramic fuel cell and its preparation method in the present application will be described in detail through embodiments.

[0088] Embodiment 1

[0089] Synthesize the cathode material by the solid-phase method, including the following steps:

[0090] Add 3.9468 g of barium carbonate, 0.321 g of cobalt(III) oxide, 0.3194 g of iron(III) oxide, 0.4929 g of zirconium oxide, 0.6810 g of praseodymium hexoxide, and 0.6028 g of tin oxide to a planetary ball mill. Then add ethanol to the ball mill and ball mill to mix evenly. Sinter the mixed material in an air atmosphere to obtain the cathode material BaCo 0.2 Fe 0.2 Zr 0.2 Sn 0.2 Pr 0.2 O 3-δ (BCFZSP), and the material is in powder form;

[0091] Among them, the ball milling conditions are: ball milling time is 24 h, and the rotation speed of the ball mill is 400 r / min; the sintering conditions are: sintering temperature is 1200 °C, and sintering time is 2 h.

[0092] Example 2

[0093] Synthesize the cathode material by the sol-gel method, including the following steps:

[0094] Dissolve 2.6134 g of barium nitrate, 2.9103 g of cobalt(II) nitrate hexahydrate, 4.04 g of iron(III) nitrate nonahydrate, 2.3123 g of zirconyl nitrate, 4.3501 g of praseodymium(III) nitrate hexahydrate, 2.6052 g of tin(IV) chloride, 4.2028 g of citric acid monohydrate, and 8.7672 g of ethylenediaminetetraacetic acid into deionized water to form a mixed solution. Then dropwise add 25% ammonia water to the mixed solution until the mixed solution becomes clear. Then heat the clear solution to form a stable gel. The formed gel is successively subjected to heat preservation and sintering to obtain the cathode material BaCo 0.2 Fe 0.2 Zr 0.2 Sn 0.2 Pr 0.2 O 3-δ (BCFZSP), and the material is in powder form;

[0095] Among them, the heating temperature is 80 °C, the heat preservation conditions are: heat preservation temperature is 250 °C, and heat preservation time is 2 h, and the sintering conditions are: sintering temperature is 1200 °C, and sintering time is 2 h.

[0096] Example 3

[0097] Synthesize the electrolyte material by the solid-phase method, including the following steps:

[0098] Add 9.867 g of barium carbonate, 1.232 g of zirconium oxide, 1.721 g of cerium oxide, 1.507 g of tin oxide, 0.799 g of titanium dioxide and 1.129 g of yttrium oxide to a planetary ball mill, then add ethanol to the ball mill for ball milling and uniform mixing. Sinter the mixed material in an air atmosphere to obtain an electrolyte material of high-entropy perovskite BaZr 0.2 Ce 0.2 Sn 0.2 Ti 0.2 Y 0.2 O 3-δ (BZCSTY), and the material is in powder form;

[0099] Among them, the ball milling conditions are: ball milling time is 24 h, and the rotation speed of the ball mill is 400 r / min; the sintering conditions are: sintering temperature is 1400 °C, and sintering time is 5 h.

[0100] Example 4

[0101] Synthesize the electrolyte material by sol-gel method, including the following steps:

[0102] Dissolve 13.067 g of barium nitrate, 2.3123 g of zirconyl nitrate, 3.2613 g of cerium nitrate, 1.8968 g of titanium tetrachloride, 2.6052 g of tin tetrachloride, 2.7492 g of yttrium nitrate, 4.2028 g of citric acid monohydrate and 8.7672 g of ethylenediaminetetraacetic acid into deionized water to form a mixed solution. Then, dropwise add 25% ammonia water to the mixed solution until the mixed solution becomes clear. Then heat the clear solution to form a stable gel. The formed gel is successively subjected to heat preservation and sintering to obtain an electrolyte material of high-entropy perovskite BaZr 0.2 Ce 0.2 Sn 0.2 Ti 0.2 Y 0.2 O 3-δ (BZCSTY), and the material is in powder form;

[0103] Among them, the heating temperature is 80 °C, the heat preservation conditions are: heat preservation temperature is 250 °C, and heat preservation time is 2 h, and the sintering conditions are: sintering temperature is 1400 °C, and sintering time is 5 h.

[0104] Example 5

[0105] Preparation of the anode material, including the following steps:

[0106] NiO was mixed with the electrolyte material BZCSTY prepared in Example 3 and starch in a 5% PVA aqueous solution, and the mixed substance was sintered to obtain the anode material. When preparing the anode material, 20 g of BZCSTY, 30 g of NiO and 15 g of corn starch were mixed with 30 mL of 5% PVA aqueous solution. The slurry after sufficient mixing was dried in an oven at 80 °C for 12 h, and the dried powder was sintered. The sintering conditions were: sintering temperature 1450 °C, sintering time 8 h.

[0107] Example 6

[0108] A preparation method of a full high-entropy proton ceramic fuel cell, comprising the following steps:

[0109] Step 1: Place the anode material, electrolyte material and cathode material in a mold in sequence, and then place the mold on a tablet press for co-pressing to form a sintering precursor with a thickness of about 1 mm, a diameter of 1 cm and a circular shape. Among them, the co-pressing conditions are: pressing pressure 20 MPa, pressing time 2 min; the cathode material is the high-entropy perovskite BCFZSP prepared in Example 1, and the mass of the cathode material is 0.04 g; the electrolyte material is the high-entropy perovskite BZCSTY prepared in Example 3, and the mass of the electrolyte material is 0.04 g; the mass of the anode material is 0.32 g, and the anode material is prepared from Example 5.

[0110] Step 2: Place the sintering precursor in Step 1 in an air atmosphere for sintering to obtain FH-PCFC (i.e., NiO-BZCSTY||BZCSTY||BCFZSP full high-entropy proton ceramic fuel cell). Among them, the sintering conditions are: sintering temperature 1450 °C, sintering time 8 h.

[0111] Comparative Example 1

[0112] A preparation method of a full high-entropy proton ceramic fuel cell. In this example, screen printing cathode was used to prepare the full high-entropy proton ceramic fuel cell, which specifically includes the following steps:

[0113] Step C1: Place the electrolyte material and the anode material in a mold in sequence, and then place the mold on a tablet press for co-pressing to form a sintering precursor. The sintering precursor was sintered in air to obtain an anode / electrolyte half-cell. Among them, the co-pressing conditions are: pressing pressure 20 MPa, pressing time 2 min; the sintering conditions are: sintering temperature 1450 °C, sintering time 8 h; the electrolyte material is the high-entropy perovskite BZCSTY prepared in Example 3, and the mass of the electrolyte material is 0.04 g; the mass of the anode material is 0.32 g, and the anode material is prepared from Example 5.

[0114] Step C2: Place 0.1 g of the cathode material, 0.008 g of ethyl cellulose, and 0.012 g of soluble starch into a volumetric flask, and add 1.5 mL of terpineol to the volumetric flask. Magnetically stir for 12 h to obtain a screen-printing paste; among them, the cathode material is the high-entropy perovskite BCFZSP prepared in Example 1.

[0115] Step C3: Print the paste in Step C2 onto the electrolyte of the anode / electrolyte half-cell by screen printing, thereby obtaining an anode-supported SOFC full cell (i.e., NiO-BZCSTY||BZCSTY||BCFZSP), and this cell is also a full high-entropy proton ceramic fuel cell.

[0116] Test and analysis:

[0117] 1. XRD test and analysis

[0118] (1) Conduct XRD test and analysis on the cathode material BaCo 0.2 Fe 0.2 Zr 0.2 Sn 0.2 Pr 0.2 O 3-δ (BCFZSP) prepared by the solid-phase method in Example 1, and the results are as Figure 1 shown; it can be seen from Figure 1 that the BCFZSP in Example 1 has a perovskite phase structure, that is, a single-phase perovskite oxide is successfully synthesized by the solid-phase method.

[0119] (2) Conduct XRD test and analysis on the cathode material BaCo 0.2 Fe 0.2 Zr 0.2 Sn 0.2 Pr 0.2 O 3-δ (BCFZSP) prepared by the sol-gel method in Example 2 above, and the test results are as Figure 2 shown; it can be seen from Figure 2 that the BCFZSP in Example 2 has a perovskite phase structure, that is, a single-phase perovskite oxide is successfully synthesized by the sol-gel method.

[0120] (3) Conduct XRD test and analysis on the electrolyte material BaZr 0.2 Ce 0.2 Sn 0.2 Ti 0.2 Y 0.2 O 3-δ (BZCSTY) prepared by the solid-phase method in Example 3, and the results are as Figure 3 shown; it can be seen from Figure 3It can be seen that BZCSTY in Example 3 has a perovskite phase structure, that is, a single-phase perovskite oxide is successfully synthesized by the solid-phase method.

[0121] (4) The electrolyte material BaZr 0.2 Ce 0.2 Sn 0.2 Ti 0.2 Y 0.2 O 3-δ (BZCSTY) prepared by the sol-gel method in Example 4 above was subjected to XRD test analysis, and the results are as Figure 4 shown; it can be seen from Figure 4 that BZCSTY in Example 4 has a perovskite phase structure, that is, a single-phase perovskite oxide is successfully synthesized by the sol-gel method.

[0122] (5) The anode material prepared in Example 5 above was subjected to XRD test analysis, and the results are as Figure 5 shown; it can be seen from Figure 5 that there are no diffraction peaks of other impurities in the anode material, indicating that neither BZCSTY nor NiO decomposed or chemically reacted during the high-temperature sintering process, further indicating good chemical compatibility between the electrolyte material and the anode.

[0123] 2. SEM test analysis

[0124] (1) The cross-section of the battery in Comparative Example 1 was subjected to SEM test analysis, and the results are as Figure 6 shown; it can be seen from Figure 6 that a battery with a porous anode and a dense electrolyte was successfully prepared.

[0125] (2) The cross-section of the battery prepared in Example 6 was subjected to SEM test analysis, and the results are as Figure 10 shown; it can be seen from Figure 10 that a battery with a porous anode and a dense electrolyte was successfully prepared, and there is closer contact between the electrolyte and both the cathode and the anode.

[0126] 3. Flexural strength test analysis

[0127] The batteries prepared in Example 6 and Comparative Example 1 were subjected to a flexural strength test. In this test, an electronic universal testing machine was used to test the flexural strength of the battery (i.e., a three-point bending test), and the loading speed during the test was 1.0 mm·min -1 . After testing, the flexural strength of the battery prepared in Example 6 was 72 ± 3.07 MPa, and the flexural strength of the battery prepared in Comparative Example 1 was 66 ± 3.57 MPa.

[0128] 4. Battery performance test

[0129] The batteries prepared in Example 6 and Comparative Example 1 were subjected to performance tests; during the tests, hydrogen gas was introduced into the anode side of the battery at a rate of 50 ml·min -1 as the carrier gas, and static air was used as the oxidant.

[0130] The performance test results of the battery prepared in Comparative Example 1 are as shown in Figure 7 、 Figure 8 and Figure 9 ; It can be seen from Figure 7 that for the all-high-entropy proton ceramic fuel cell NiO-BZCSTY||BZCSTY||BCFZSP prepared by screen-printing the cathode in Comparative Example 1, the maximum power densities at 500 °C, 550 °C, 600 °C, 650 °C, and 700 °C can reach 0.19, 0.33, 0.46, 0.59, and 0.77 W·cm -2 respectively;

[0131] It can be seen from Figure 8 that for the battery prepared in Comparative Example 1, in an air atmosphere at 650 °C, the total impedance of the whole cell is about 0.36 Ω·cm -2 ;

[0132] It can be seen from Figure 9 that for the battery prepared in Comparative Example 1, at a working temperature of 550 °C, with a constant current output at a current density of 0.34 A·cm -2 , a certain degree of performance decay occurred during the 500-h stability test, and the decay rate obtained by fitting was 0.12 W per thousand hours.

[0133] The test results of the battery in Example 6 are as shown in Figure 11 、 Figure 12 and Figure 13 ; It can be seen from Figure 11 that for the all-high-entropy proton ceramic fuel cell NiO-BZCSTY||BZCSTY||BCFZSP prepared by the one-step co-pressing method in the present invention, the maximum power densities at 500 °C, 550 °C, 600 °C, 650 °C, and 700 °C can reach 0.29, 0.41, 0.56, 0.79, and 1.02 W·cm -2 respectively;

[0134] It can be seen from Figure 12 that for the battery prepared in Example 6, in an air atmosphere at 650 °C, the total impedance of the whole cell is about 0.30 Ω·cm -2 ;

[0135] It can be seen from Figure 13 that for the battery prepared in Example 6, at a working temperature of 550 °C, with a constant current output at a current density of 0.34 A·cm -2 , the decay rate obtained by fitting is 1.36×10-4 W / kWh

[0136] In summary, the maximum power density, stability, low resistance, and mechanical strength of the full high-entropy proton ceramic fuel cell prepared by one-step co-pressing in this application are significantly better than those of the full high-entropy proton ceramic fuel cell prepared by screen printing the cathode.

[0137] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A full high-entropy proton ceramic fuel cell, characterized in that, it includes a cathode, an electrolyte and an anode; wherein, both the cathode material and the electrolyte material are high-entropy perovskites; the anode material includes NiO and high-entropy perovskite; the cathode material is a high-entropy perovskite with the chemical formula LnXnO3-δ, where Ln is Ba, and Xn is composed of any three elements among Co, Fe, Zr, Sn, Pr, Nb, Mo, Mn, Ni, Cu and Zn and the constituent elements have an equal atomic ratio; wherein, δ is the oxygen vacancy content; the electrolyte material is a high-entropy perovskite with the chemical formula BaYnO3-δ, where Yn is composed of any three elements among Zr, Ce, Sn, Ti, Y, Nb, Mo, Mn, Ni, Cu and Zn and the constituent elements have an equal atomic ratio; wherein, δ is the oxygen vacancy content; the high-entropy perovskite in the anode material is a high-entropy perovskite with the chemical formula BaYnO3-δ, where Yn is composed of any three elements among Zr, Ce, Sn, Ti, Y, Nb, Mo, Mn, Ni, Cu and Zn and the constituent elements have an equal atomic ratio; wherein, δ is the oxygen vacancy content.

2. The full high-entropy proton ceramic fuel cell according to claim 1, characterized in that, the cathode material is BaCo0.2Fe0.2Zr0.2Sn0.2Pr0.2O3-δ; wherein, δ is the oxygen vacancy content.

3. The full high-entropy proton ceramic fuel cell according to claim 1, characterized in that, the electrolyte material is BaZr0.2Ce0.2Sn0.2Ti0.2Y0.2O3-δ; wherein, δ is the oxygen vacancy content.

4. The full high-entropy proton ceramic fuel cell according to claim 1, characterized in that, the mass percentage of the high-entropy perovskite and NiO in the anode material is 30% - 70%.

5. The preparation method of the full high-entropy proton ceramic fuel cell according to any one of claims 1 - 4, characterized in that, it includes the following steps: Step 1, first place the anode material, the electrolyte material and the cathode material in a mold in sequence, and then co-press them into a sintering precursor; Step 2, sinter the sintering precursor to obtain a full high-entropy proton ceramic fuel cell after sintering.

6. The preparation method of the full high-entropy proton ceramic fuel cell according to claim 5, characterized in that, the mass ratio of the cathode material to the electrolyte material in Step 1 is 1:2 - 2:1; the mass ratio of the cathode material to the anode material is 1:5 - 1:

10.

7. The preparation method of the full high-entropy proton ceramic fuel cell according to claim 5, characterized in that, the pressure for co-pressing in Step 1 is 18 - 25 MPa, and the co-pressing time is 1 - 3 min.

8. The preparation method of the full high-entropy proton ceramic fuel cell according to claim 5, characterized in that, the sintering conditions in Step 2 are: the sintering temperature is 1200 - 1480 °C, and the sintering time is 8 - 12 h.

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