PCEC proton conductor electrolyte, preparation thereof and application of PCEC proton conductor electrolyte in high-humidity continuous in-situ hydrogenation upgrading of biomass pyrolysis gas

Abstract

The invention relates to a PCEC proton conductor electrolyte, preparation thereof and application of the PCEC proton conductor electrolyte in high-humidity continuous in-situ hydrogenation upgrading of biomass pyrolysis gas, the proton conductor electrolyte is composed of a PCEC fuel electrode support body, and a BZCY proton conductor layer and an NCO proton conductor layer which are sequentially arranged on the surface of the PCEC fuel electrode support body, a NiO-BZCY / BZCY / NCO in-situ protection interface structure is formed by the contact surface of the BZCY proton conductor layer and the NCO proton conductor layer, the NCO proton conductor layer is made of A2B2O7 type fluorite structure oxide Nd2Ce2O7, the BZCY proton conductor layer is made of ABO3 type perovskite structure oxide BaZrxCeyY1-x-yO3-delta (BZCY, x + y + z is larger than or equal to 0 and smaller than or equal to 1, and y is not equal to 0. The preparation method comprises the following steps: respectively synthesizing NCO and BZCY proton conductors, spin-coating to construct a heterogeneous interface, forming a PCEC green body, sintering at high temperature, and optimizing a coating process and sintering conditions to form the PCEC single electrolytic cell with high compactness and excellent interface synergistic effect. Compared with the prior art, the method has higher electrochemical stability, water vapor corrosion resistance and long-period operation performance, and shows wide industrial application potential.

Description

Technical Field

[0001] The present invention belongs to the field of proton conducting electrolytic cell (PCEC) electrolyte interface construction, and relates to a PCEC proton conducting electrolyte and its preparation and application in high-humidity continuous in-situ hydrogenation and upgrading of biomass pyrolysis gas. Background Art

[0002] PCEC (Protonic Ceramic Electrochemical Cell) is an advanced electrochemical device based on proton conductor ceramic materials as electrolyte. + The core advantage of PCEC comes from the proton conductor ceramic electrolyte material it uses. This type of material is usually doped with barium cerium zirconium oxide BaZr x Ce y Y 1-x-y O 3-δ (BZCY) is based on a high proton conductivity. Compared with the oxygen ions (O 2 -) conductive electrolyte, PCEC greatly reduces the ion migration resistance inside the battery through the proton conduction mechanism, effectively lowering the battery operating temperature (usually between 500-700℃), thereby improving the energy conversion efficiency.

[0003] The application field of PCEC is very wide. It can be used as a fuel cell for clean and efficient electricity production, and can also be used for chemical synthesis and gas quality improvement in electrolysis mode, such as the preparation of green hydrogen through water vapor electrolysis, or the purification and quality improvement of gas fuels through electrocatalytic reactions. In the process of producing valuable chemical products in the medium temperature range of PCEC, increasing the water vapor concentration on the air electrode side is an effective way to improve the efficiency of electrochemical reactions. Water vapor can accelerate the oxygen reduction reaction (ORR) at the air electrode, promote the generation and migration of protons, thereby significantly reducing the interfacial impedance and improving the output power and overall energy conversion efficiency of PCEC. However, although BZCY-based electrolytes have excellent proton conductivity, in a high humidity environment, Ce 3+The cerium oxide (CeO2) readily reacts with water vapor, forming a chemically stable but non-conductive CeO2 precipitate. This non-conductive cerium oxide precipitate gradually occupies the proton conduction pathway, significantly decreasing the overall conductivity of the electrolyte and gradually degrading battery performance. Furthermore, high water vapor concentrations accelerate the decomposition of the BZCY lattice, particularly due to the relatively stable solid solution of Zr and the poor chemical stability of Ce. This leads to increased stress within the lattice and ultimately causes phase separation and microcracks. This microstructural disruption not only weakens the continuity of proton transport but also reduces the mechanical strength of the electrolyte, making PCEC more susceptible to mechanical failure during long-term operation. This contradiction represents a core bottleneck in the current development of PCEC technology: while increasing the water vapor concentration on the air electrode side helps improve electrochemical efficiency, it accelerates chemical degradation of the electrolyte and shortens its service life. In practical applications, this manifests as a significant trade-off between operating efficiency and material life, limiting the reliability of PCEC during long-term stable operation. Resolving this contradiction and improving the moisture stability of the electrolyte are key challenges for future PCEC technology upgrades and industrial expansion.

[0004] Patent CN202410820495.6 proposes a proton ceramic battery design based on a double-layer electrolyte structure. 0.8 Nb 0.2 O 3-δ As the first electrolyte layer, it provides excellent proton conductivity and introduces BaZr 0.2 Ce 0.6 Y 0.2 O 3-δ It serves as the second electrolyte layer to enhance structural stability, thereby effectively improving the Faraday efficiency and electrochemical performance of the battery. The preparation process adopts physical vapor deposition (PVD) and pulsed laser deposition (PLD) technology to ensure the high density and interfacial bonding strength of the electrolyte film. However, this design still has some significant defects: first, the PVD and PLD process equipment are expensive and complicated to operate, making it difficult to meet the cost and efficiency requirements of large-scale industrial production; second, the patent does not provide long-term (>400 hours) stability data, especially the lack of strong verification of the electrochemical performance retention during water vapor electrolysis under high humidity conditions; finally, the selected materials are highly dependent on rare metals, which further increases the cost and difficulty of resource acquisition. Therefore, although this design exhibits high electrochemical performance under laboratory conditions, it faces greater cost and reliability challenges in actual industrial applications.

[0005] Patent CN201710232995.8 proposes a low-temperature solid oxide fuel cell (SOFC) based on a double-layer electrolyte design, the structure of which includes an anode support, a cerium-based or zirconium-based dense electrolyte layer, a bismuth oxide-based dense electrolyte layer, and a composite cathode active layer. The design idea is to cover the cerium-based or zirconium-based electrolyte with a bismuth oxide-based electrolyte layer to isolate the direct contact between bismuth oxide and the reducing gas, suppress the risk of decomposition, and thus achieve efficient oxygen ion conduction under low temperature (300–600°C) conditions and reduce the internal resistance of the battery. However, this design fails to completely solve the problem of electronic conductivity generated by cerium-based electrolytes under low oxygen partial pressure, resulting in a low open circuit voltage (OCV), far from theoretical expectations, which in turn affects the overall energy conversion efficiency of the battery. In addition, although the double-layer electrolyte structure optimizes low-temperature performance, its stability under long-term operation lacks sufficient verification, which limits the reliability and life performance of practical applications. Summary of the Invention

[0006] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a PCEC proton conductor electrolyte and its preparation and application in high-humidity continuous in-situ hydrogenation and upgrading of biomass pyrolysis gas, effectively solving the chemical stability problem of traditional PCEC in a high water vapor environment, and can also achieve long-term stable continuous original hydrogenation and upgrading in a high-humidity environment of biomass pyrolysis gas, with excellent hydrogenation and upgrading efficiency, significantly improving the energy conversion efficiency and product purity of biomass gas, and providing a new technical path for the efficient conversion and industrial application of clean energy.

[0007] The object of the present invention can be achieved by the following technical solution: a proton conductor electrolyte of PCEC, which comprises a PCEC fuel electrode support and a BZCY proton conductor layer and an NCO proton conductor layer sequentially arranged on its surface, wherein the contact surface of the BZCY proton conductor layer and the NCO proton conductor layer constitutes an in-situ protected interface structure of NiO-BZCY / BZCY / NCO, the material of the NCO proton conductor layer is A2B2O7 type fluorite structure oxide Nd2Ce2O7, and the material of the BZCY proton conductor layer includes ABO3 type perovskite structure oxide BaZr x Ce y Y 1-x-y O 3-δ (BZCY), 0≤x+y+z≤1, y≠0.

[0008] Furthermore, the in-situ protected interface structure of NiO-BZCY / BZCY / NCO couples the high water resistance of NCO with the element diffusion characteristics of Ba prepared at high temperature to form a protective structure with excellent interface synergistic effect. The thickness of the BZCY proton conductor layer is 2.5-3 μm, and the thickness of the NCO proton conductor layer is 2-2.5 μm.

[0009] The present invention also provides a method for preparing a proton conductor electrolyte of PCEC as claimed in claim 1, comprising the following steps:

[0010] S1: Preparation of NCO proton conductor powder: Preparation is carried out by a citrate-nitrate one-step combustion method, wherein soluble neodymium salt and cerium salt are deionized in water to obtain a clear salt solution; citric acid is dissolved in water to obtain an acid solution; the salt solution and the acid solution are uniformly stirred and mixed, the pH is adjusted to 7-8, and a closed reaction is carried out at a constant temperature to allow the citric acid to fully complex with the metal cations, evaporate to form a gel, and spontaneously combust to form a powder, which is then calcined to obtain a nano-scale NCO phase powder;

[0011] S2: Preparation of BZCY proton conductor powder: Cerium salt, zirconium salt, barium salt, and yttrium salt are sequentially dissolved in water, the resulting salt solution is poured into a citric acid solution, and then ethylene glycol is added to the solution to adjust the pH of the solution to 8-9 until the flocs in the solution disappear. The solution is heated at a constant temperature to form a viscous white gel; the gel is rapidly heated, dried, and vigorously burned to obtain a white-yellow powder, which is crushed and calcined at a high temperature to obtain BZCY proton conductor powder;

[0012] S3: Preparation of NCO proton conductor slurry: The nano-scale NCO phase powder prepared in step S1 is dried and ground, then mixed with a dispersion medium, and a binder and a surfactant are added, mixed in a ball mill, and then subjected to ultrasonic dispersion treatment to further eliminate agglomerates;

[0013] S4: Preparation of BZCY proton conductor slurry: The BZCY proton conductor powder prepared in step S2 is dried and ground, then mixed with a dispersion medium, and a binder and a surfactant are added, mixed on a ball mill, and then ultrasonically dispersed to further eliminate agglomerates;

[0014] S5: Preparation of PCEC fuel electrode support: NiO, BZCY proton conductor powder obtained in step S2, and nanographite powder are placed in a ball mill and wet-milled with ethanol to mix them thoroughly to obtain fuel electrode powder; the fuel electrode powder is compression molded to obtain a fuel electrode support green body, and the PCEC fuel electrode support is obtained after heat treatment;

[0015] S6: Electrolyte heterogeneous interface construction: the fuel electrode support prepared in step S5 is placed in a vacuum spin coater, and the BZCY proton conductor slurry prepared in step S4 is evenly coated on its surface to form a uniform BZCY proton conductor coating, and then the NCO proton conductor slurry prepared in step S3 is spin-coated on the surface of the BZCY proton conductor to form a uniform BZCY / NCO proton conductor coating to obtain a semi-electrolytic cell NiO-BZCY / BZCY / NCO, which is placed in a high-temperature resistance furnace and heated in air atmosphere. The temperature was raised to 1100-1200°C at a rate of 4-6°C / min and kept at this temperature for 0.5-1.5h. Subsequently, the temperature was raised to 1400-1500°C at a rate of 2-4°C / min and kept at this temperature for 4-6h to completely sinter the electrolyte into a dense state. The temperature was then lowered to 1100-1300°C at a rate of 1-3°C / min and kept at this temperature for 0.5-1.5h. Finally, the temperature was lowered to 750-850°C at a rate of 2-4°C / min, the power was turned off, and the furnace was cooled to room temperature to obtain an electrolyte with a BZCY / NCO heterogeneous interface.

[0016] Furthermore, in step S1, the neodymium salt is Nd(NO3)3·6H2O, and the cerium salt is Ce(NO3)3·6H2O; the neodymium salt and the cerium salt are weighed according to a stoichiometric ratio of a chemical composition of Nd2Ce2O7;

[0017] The amount of citric acid added is such that the molar ratio of the metal cation to the citric acid in the salt solution is 1:1.5-2;

[0018] Use ammonia water with a mass concentration of 15% to 20% to adjust the pH value;

[0019] The temperature of the constant temperature heating closed reaction is 65-75°C. The calcination is to calcine the powder formed by spontaneous combustion at 500-600°C for 0.1-1h to remove residual organic matter in the powder, and then calcine at 750-850°C for 2-4 hours to obtain nano-scale NCO phase powder.

[0020] Furthermore, in step S2, the barium salt is Ba(NO3)2, the zirconium salt is Zr(NO3)4·5H2O, and the cerium salt is H8CeN8O 18 , yttrium salt, cerium salt, zirconium salt, barium salt, yttrium salt according to BaZr x Ce y Y 1-x-y O 3-δ Weigh the stoichiometric ratio;

[0021] The molar ratio of the metal cation to the ethylene glycol and citric acid in the salt solution is 1:1.5-2:1.5-2;

[0022] Use ammonia water with a mass concentration of 15%-20% to adjust the pH value;

[0023] The constant temperature heating reaction temperature is 75-85°C and the time is 7-8h;

[0024] The rapid heating of the gel is to heat it to 250-350° C., dry it into a porous solid material, and then burn it violently to obtain a white-yellow powder. The calcination is to keep it at 1100-1300° C. for 4-6 hours and then cool it with the furnace.

[0025] Furthermore, in step S3, the mass ratio of the nano-scale NCO phase powder to the dispersion medium is 5 to 7:4;

[0026] Based on the total weight of the nano-scale NCO phase powder and the dispersion medium as 100%, the added amount of the binder is 3-4%; the added amount of the surfactant is 5-7%;

[0027] The dispersion medium is a terpineol solution containing 1-2 wt% ethyl cellulose;

[0028] The binder is polyvinyl butyral;

[0029] The surfactant is polyethylene glycol;

[0030] The rotation speed of the ball mill is 450-500 rpm; the ball milling time is 10-14 hours; and the ultrasonic dispersion time is 30-40 minutes.

[0031] Furthermore, in step S4, the mass ratio of BZCY proton conductor powder to dispersion medium is 6 to 8:3;

[0032] Based on the total weight of the BZCY proton conductor powder and the dispersion medium as 100%, the added amount of the binder is 2-3%; the added amount of the surfactant is 3-5%;

[0033] The dispersion medium is a terpineol solution containing 1-2 wt% ethyl cellulose;

[0034] The binder is polyvinyl butyral;

[0035] The surfactant is polyethylene glycol;

[0036] The rotation speed of the ball mill is 450-500 rpm, the ball milling time is 10-14 hours, and the ultrasonic dispersion time is 30-40 minutes.

[0037] Furthermore, in step S5, the mass ratio of NiO, the BZCY proton conductor powder obtained in step S2, and the nano-graphite powder is 6:4:1, the speed of the ball mill is 350-400 rpm, and the ball milling time is 10-14 hours; the axial pressing pressure of the fuel electrode powder molding is 250-300 MPa, and the holding time is 2-4 minutes; the fuel electrode support green body is heat treated in an air atmosphere at a heating rate of 4-6°C / min to 900-1100°C, holding for 0.5-1.5 hours, and then cooling to 750-850°C at a cooling rate of 2-4°C / min, and then turning off the power and cooling to room temperature with the furnace;

[0038] Furthermore, in step S6, the BZCY proton conductor slurry is coated on the surface of the fuel electrode support by spin coating. The specific operation is as follows: the BZCY proton conductor slurry is spin-coated on the surface of the fuel electrode support, the spin coating speed is controlled at 1500-2000 rpm, the acceleration is 250-350 rpm / s, and it is maintained for 15-25 seconds; then the vacuum spin coater is accelerated from 250-350 rpm / s to 5000-5500 rpm and maintained for 55-65 seconds for rapid thin film processing, and after drying at 75-85°C for 1-3 hours, the above operation is repeated;

[0039] The debinding process is to heat the temperature to 550-650°C at a heating rate of 1-2°C / min and perform debinding for 1-3 hours;

[0040] The NCO proton conductor slurry is spin-coated on the surface of the BZCY proton conductor by the following method: the fuel electrode support covered with the BZCY proton conductor coating is debonded and placed back in a vacuum spin coater, the spin coating speed is controlled at 2000-2500 rpm, the acceleration is 450-550 rpm / s, and the speed is maintained for 25-35 seconds; then the vacuum spin coater is accelerated from 450-550 rpm / s to 6000-6500 rpm and the speed is maintained for 45-55 seconds for rapid thin film processing;

[0041] The thickness of the BZCY / NCO heterojunction interface of the obtained electrolyte is 4-5 μm.

[0042] The present invention also provides an application of a proton conductor electrolyte of PCEC, and the proton conductor electrolyte PCEC is applied to the continuous in-situ hydrogenation and upgrading of biomass pyrolysis gas in a high-humidity environment.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] (1) The present invention optimizes the interface structure of the proton conductor material in the Proton Conducting Electrolytic Cell (PCEC) to achieve efficient catalytic quality improvement of pyrolysis gas under high humidity environment, that is, the Nd2Ce2O7 (NCO) proton conductor and BaZr x Ce y Y 1-x-y O 3-δ (BZCY) and other Ce-containing proton conductors are made into two different components of proton conductor powders: BZCY proton conductor powder and NCO proton conductor powder. The prepared BZCY proton conductor powder is then coated on the surface of the PCEC fuel electrode support by a slurry coating-spin coating method to form a BZCY proton conductor layer. Then, the NCO proton conductor powder slurry is evenly coated on the surface of the BZCY proton conductor layer and other Ce-containing proton conductors to form a specific NiO-BZCY / BZCY / NCO in-situ protective interface structure. The high water resistance of NCO and the element diffusion characteristics of Ba prepared at high temperature are coupled to form a synergistic protective structure (resistance to high-humidity decomposition and electron blocking); the obtained PCEC green body is formed and sintered to achieve a close combination between the heterogeneous proton conductor interface and the supporting electrolyte, forming a PCEC single electrolytic cell structure with excellent interface synergistic effect, achieving stable open circuit voltage under high humidity conditions, increased hydrogen yield and continuous in-situ quality improvement of biomass pyrolysis gas.

[0045] (2) The present invention realizes the long-term stable operation of the electrolyte material under high water vapor partial pressure conditions by constructing a PCEC heterogeneous proton conductor interface, while significantly improving the proton migration efficiency and interface reaction activity, effectively solving the problem of rapid conductivity decay caused by CeO2 precipitation in traditional BZCY-based electrolytes under high water vapor conditions, and significantly enhancing the water vapor corrosion resistance of the most widely used Ce-containing proton conductor electrolyte material, thereby realizing the long-term stable operation of the PCEC device in a high humidity environment.

[0046] (3) By optimizing the heterogeneous interface design, the present invention improves the electrolyte's anti-water vapor stability while cleverly utilizing the migration characteristics of Ba elements during high-temperature sintering to in-situ generate a nano-scale in-situ electron blocking layer. This effectively suppresses the Ce 4+ Reduced to trivalent Ce 3+ The resulting n-type electronic conductivity significantly improves the stability of the open circuit voltage and output performance.

[0047] (4) By enhancing the electrolyte's water vapor stability and electrochemical reactivity, this invention significantly expands the application potential of PCEC in high-humidity biomass pyrolysis gas environments. Its optimized design enables efficient and continuous in-situ hydrogenation and upgrading reactions under high-humidity conditions, effectively improving the energy density and purity of the gas products, and providing more competitive technical support for the preparation and industrialization of clean fuels.

[0048] (5) The preparation process adopted in the present invention is simple, including high-energy ball milling, vacuum spin coating, multi-step sintering and other steps, which is easy to achieve mass production, reduces manufacturing costs, and has good industrial application potential. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 The BaZr prepared in Example 1 0.1 Ce 0.8 Y 0.1 O 3-δ Cross-sectional SEM image of the Nd2Ce2O7 heterogeneous electrolyte on the porous fuel electrode. The upper layer is the Nd2Ce2O7 proton conductor and the middle layer is BaZr 0.1 Ce 0.8 Y 0.1 O 3-δ Proton conductor. The total thickness of the electrolyte is 5.26μm;

[0050] Figure 2 BaZr prepared in Comparative Example 1 0.1 Ce 0.8 Y 0.1 O 3-δ Cross-sectional SEM image of the electrolyte on the porous fuel electrode. The electrolyte layer contains only BaZr 0.1 Ce 0.8 Y 0.1 O 3-δ Proton conductor. The total thickness of the electrolyte is 5.26μm;

[0051] Figure 3 This is a cross-sectional SEM image of the Nd2Ce2O7 electrolyte prepared in Comparative Example 2 on a porous fuel electrode. The electrolyte layer contains only the Nd2Ce2O7 proton conductor. The total thickness of the electrolyte is 5.21 μm.

[0052] Figure 4 These are the long-term stability test results of the electrolytic cells with BZCY and BZCY / NCO electrolyte structures prepared in Example 1 and Comparative Example 1 for in-situ hydrogenation and upgrading of biomass pyrolysis gas at 650°C, a DC voltage of 1.3V, and a high humidity environment. DETAILED DESCRIPTION

[0053] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0054] The present invention optimizes the interface structure of the proton conductor material in the Proton Conducting Electrolytic Cell (PCEC) to achieve efficient catalytic improvement of pyrolysis gas in a high humidity environment. The preparation process of the heterogeneous proton conductor interface material includes the separate synthesis of two different components of proton conductor powders, namely Nd2Ce2O7 (NCO) proton conductor and BaZr x Ce y Y 1-x-y O 3-δ (BZCY) and other Ce-containing proton conductors; the electrolyte interface structure construction process adopts a slurry coating-spin coating method to uniformly coat the prepared NCO proton conductor powder slurry on the surface of BZCY and other Ce-containing proton conductors to form a specific NiO-BZCY / BZCY / NCO in-situ protective interface structure, coupling the high water resistance of NCO with the element diffusion characteristics of Ba prepared at high temperature to form a synergistic protective structure (resistance to high-humidity decomposition and electron blocking); the PCEC green body forming and sintering steps include drying after coating and high-temperature sintering according to a specific heating curve to achieve close bonding between the heterogeneous proton conductor interface and the supporting electrolyte, forming a PCEC semi-electrolytic cell structure with excellent interface synergistic effect, achieving stable open circuit voltage under high humidity conditions, increased hydrogen yield and continuous in-situ quality improvement of biomass pyrolysis gas.

[0055] Unless otherwise specified, the raw materials and equipment used in the present invention are all commonly used commercially available raw materials and equipment in this field. The technical solution of the present invention will be described in detail below with reference to the accompanying drawings.

[0056] Example 1

[0057] A proton conductor electrolyte of PCEC is prepared by the following method:

[0058] Preparation of S1: NCO proton conductor powder: The powder was prepared using a citrate-nitrate one-step combustion method. 672.52 g (2 mol) of Nd(NO3)3·6H2O and 868.44 g (2 mol) of Ce(NO3)3·6H2O were weighed in a stoichiometric ratio of Nd2Ce2O7. All raw materials were dissolved in deionized water with heating and stirring to obtain a clear nitrate solution. Based on the metal cations in the nitrate solution, 1260.84 g (6 mol) of citric acid (CA) was weighed in a molar ratio of metal cation: citric acid (CA) = 1:1.5. CA was then dissolved in ultrapure water. The resulting mixed solution was uniformly stirred. 20% ammonia water was slowly added dropwise to adjust the pH of the solution to 8. The mixture was heated at 70°C in a sealed, thermostatic water bath with continuous stirring for 12 hours to allow for the complete complexation of CA with the metal cations. The plastic film was then removed and heating and stirring continued until the water evaporated, forming a viscous, brown gel. The gel was heated in an electric furnace until it spontaneously combusted, forming a fluffy, pale yellow powder. The resulting product was then held at 550°C for 0.5 hours to remove any residual organic matter, and then calcined at 800°C for 3 hours to obtain a nano-sized NCO phase powder.

[0059] S2:BaZr 0.1 Ce 0.8 Y 0.1 O 3-δ Preparation of proton conductor powder: According to BaZr 0.1 Ce 0.8 Y 0.1 O 3-δ Stoichiometric ratio: weigh 261.34g (1 mol) Ba(NO3)2, 33.93g (0.1 mol) Zr(NO3)4·5H2O, 507.39g (0.8 mol) H8CeN8O 18 , 43.33g (0.1mol) Y(NO3)3·6H2O and ethylene glycol and citric acid were weighed in a molar ratio of 1:2:2 between metal cations and 124.14g (4mol) ethylene glycol and 420.28g (4mol) citric acid. 18 Dissolve Zr(NO₃)₄·5H₂O, Ba(NO₃)₂, and Y(NO₃)₃·6H₂O in 50 mL of distilled water, in that order. Pour the resulting nitrate solution into 300 mL of citric acid solution, then add ethylene glycol. Add 15% aqueous ammonia dropwise to the solution, adjusting the pH to 8 until the flocs disappear. Heat in a constant-temperature water bath at 80°C for 8 hours to form a viscous white gel.

[0060] The gel was rapidly heated to 300°C in an electric furnace, dried into a porous solid, and then burned vigorously to obtain a white-yellow powder. The obtained white-yellow powder was crushed, kept at 1200°C for 5 hours, and cooled in the furnace to obtain BZCY proton conductor powder.

[0061] S3: Preparation of NCO proton conductor coating-spin coating slurry: 0.6 g of the nanoscale NCO phase powder prepared in step S1 was dried and ground, and then mixed with a dispersion medium (a terpineol solution containing 1 wt% ethyl cellulose) in a mass ratio of 6:4. At the same time, 3 wt% of a binder (polyvinyl butyral, PVB) and 5 wt% of a surfactant (polyethylene glycol PEG) were added. The mixture was mixed at 450 rpm on a ball mill for 12 hours, and then ultrasonically dispersed for 30 minutes to further eliminate agglomerations.

[0062] S4: Preparation of BZCY proton conductor coating-spin coating slurry: 0.7 g of the BZCY proton conductor powder prepared in step S2 was dried and ground, and then mixed with a dispersion medium (terpineol solution containing 4 wt% ethyl cellulose) in a mass ratio of 7:3, and 3 wt% binder (polyvinyl butyral, PVB) and 3 wt% surfactant (polyethylene glycol PEG) were added. The mixture was mixed on a ball mill at a speed of 500 rpm for 12 hours, and then ultrasonic dispersion treatment was performed for 40 minutes to further eliminate agglomerations.

[0063] S5: Preparation of PCEC fuel electrode support: 0.6g NiO, 0.4g BZCY proton conductor powder (prepared in step S2), and 0.1g nanographite powder were placed in a ball mill and wet-milled with ethanol. Mill at 400 rpm for 12 hours to thoroughly mix the mixture to obtain a fuel electrode powder. 0.30g of the fuel electrode powder was slowly poured into a 13mm diameter circular mold, gently shaken to spread it flat within the mold, and lightly pre-pressed. The powder was then co-pressed on a manual tablet press, maintaining an axial pressure of 250 MPa for 3 minutes. The resulting fuel electrode support green body was placed in a high-temperature resistance furnace and heated to 1000°C at a rate of 5°C / min in air atmosphere for 1 hour. The temperature was then lowered to 800°C at a rate of 3°C / min. The furnace was then turned off and cooled to room temperature.

[0064] S6: Electrolyte heterogeneous interface construction: First, place the heat-treated PCEC fuel electrode support prepared in step S5 in a vacuum spin coater. Use a micropipette to apply 50 μL of the BZCY proton conductor slurry prepared in step S4 to the surface of the heat-treated fuel electrode support. The spin coating speed is controlled at 1500 rpm, the acceleration is 300 rpm / s, and the speed is maintained for 20 seconds. After the BZCY proton conductor slurry is evenly distributed on the surface, the speed is increased from 300 rpm / s to 5000 rpm and maintained for 60 seconds for rapid thin film processing. After drying at 80°C for 2 hours, the above operation is repeated once to form a uniform BZCY proton conductor coating. After spin coating, the binder is removed at 600°C for 2 hours, with a heating rate of 1°C / min. The fuel electrode support covered with the BZCY proton conductor coating was placed back in the vacuum spin coater, and 30 μL of the NCO proton conductor slurry prepared in step S3 was applied to the surface of the heat-treated BZCY proton conductor. The spin coating speed was controlled at 2500 rpm, the acceleration was 500 rpm / s, and the speed was maintained for 30 s. After the NCO proton conductor slurry was evenly distributed on the surface, the speed was increased from 500 rpm / s to 6500 rpm and maintained for 50 s for rapid thin film treatment to form a uniform BZCY / NCO proton conductor coating. The obtained semi-electrolytic cell (NiO-BZCY / BZCY / NCO) was placed in a high-temperature resistance furnace, and heated to 1100°C at a heating rate of 5°C / min in an air atmosphere and kept warm for 1 hour, then heated to 1450°C at a heating rate of 3°C / min and kept warm for 5 hours to completely sinter the electrolyte, and then cooled to 1200°C at a cooling rate of 2°C / min and kept warm for 1 hour, and finally cooled to 800°C at a cooling rate of 3°C / min, and then turned off the power and cooled to room temperature with the furnace, thus obtaining a proton conductor electrolyte of the PCEC fuel electrode support and the BZCY proton conductor layer and the NCO proton conductor layer sequentially arranged on its surface. Among them, the contact surface of the BZCY proton conductor layer and the NCO proton conductor layer is as follows: Figure 1 As mentioned above, the thickness is 5.26 μm.

[0065] Comparative Example 1

[0066] This comparative example does not contain an NCO proton conductor layer, and the preparation method is as follows:

[0067] S1:1mol BaZr 0.1 Ce 0.8 Y 0.1 O 3-δ Preparation of proton conductor powder: According to BaZr 0.1 Ce 0.8 Y 0.1 O 3-δStoichiometric ratio: weigh 261.34g (1 mol) Ba(NO3)2, 33.93g (0.1 mol) Zr(NO3)4·5H2O, 507.39g (0.8 mol) H8CeN8O 18 , 43.33g (0.1mol) Y(NO3)3·6H2O and ethylene glycol and citric acid were weighed in a molar ratio of 1:2:2 between metal cations and 124.14g (4mol) ethylene glycol and 420.28g (4mol) citric acid. 18 , Zr(NO3)4·5H2O, Ba(NO3)2, and Y(NO3)3·6H2O were dissolved in 50 mL of distilled water in that order. The resulting nitrate solution was poured into 300 mL of citric acid solution, and then ethylene glycol was added to the solution. 15% ammonia water was added dropwise to the solution, and the pH value of the solution was adjusted to 8 until the flocs in the solution disappeared. The solution was heated at 80°C in a constant temperature water bath for 8 hours to form a viscous white gel. The gel was rapidly heated to 300°C in an electric furnace and dried into a porous solid material, which then burned violently to obtain a white-yellow powder. The obtained white-yellow powder was pulverized, kept at 1200°C for 5 hours, and cooled in the furnace to obtain BZCY proton conductor powder.

[0068] S2: Preparation of BZCY proton conductor coating-spin coating slurry: 0.7 g of the BZCY proton conductor powder obtained in step S1 was dried and ground, and then mixed with a dispersion medium (terpineol solution containing 4 wt% ethyl cellulose) in a mass ratio of 7:3, and 3 wt% binder (polyvinyl butyral, PVB) and 3 wt% surfactant (polyethylene glycol PEG) were added. The mixture was mixed on a ball mill at a speed of 500 rpm for 12 hours, and then ultrasonic dispersion treatment was performed for 40 minutes to further eliminate agglomerations.

[0069] S3: Preparation of PCEC fuel electrode support: 0.6g NiO, 0.4g BZCY proton conductor powder prepared in step S1, and 0.1g nanographite powder were placed in a ball mill and wet-milled with ethanol. Mill at 400 rpm for 12 hours to thoroughly mix the mixture to obtain a fuel electrode powder. 0.30g of the fuel electrode powder was slowly poured into a 13mm diameter circular mold, gently shaken to spread it flat within the mold, and lightly pre-pressed. The powder was then co-pressed on a manual tablet press, maintaining an axial pressure of 250 MPa for 3 minutes. The resulting fuel electrode support green body was placed in a high-temperature resistance furnace and heated to 1000°C at a rate of 5°C / min in air atmosphere for 1 hour. The temperature was then decreased to 800°C at a rate of 3°C / min. The furnace was then turned off and cooled to room temperature.

[0070] S4: Electrolyte Interface Construction: First, the heat-treated PCEC fuel electrode support prepared in step S3 was placed in a vacuum spin coater. 50 μL of the BZCY proton conductor slurry prepared in step S2 was applied to the heat-treated fuel electrode support surface using a micropipette. The spin coating speed was controlled at 1500 rpm with an acceleration of 300 rpm / s for 20 seconds. After the BZCY proton conductor slurry was evenly distributed on the surface, the acceleration was increased from 300 rpm / s to 5000 rpm and maintained for 60 seconds for rapid thin film formation. After drying at 80°C for 2 hours, the above operation was repeated twice to form a uniform BZCY proton conductor coating. After spin coating, the coating was debonded at 600°C for 2 hours. The obtained half electrolytic cell (NiO-BZCY / BZCY) was placed in a high-temperature resistance furnace, and heated to 1100°C at a rate of 5°C / min in air atmosphere and kept at this temperature for 1 hour. Then, the temperature was raised to 1450°C at a rate of 3°C / min and kept at this temperature for 5 hours to completely sinter the electrolyte. The temperature was then lowered to 1200°C at a rate of 2°C / min and kept at this temperature for 1 hour. Finally, the temperature was lowered to 800°C at a rate of 3°C / min, and the power was turned off and the furnace was cooled to room temperature. Figure 2 As mentioned above, the thickness is 5.17 μm.

[0071] Comparative Example 2

[0072] This comparative example does not contain a BZCY proton conductor layer, and the preparation method is as follows:

[0073] Preparation of S1:1 mol NCO proton conductor powder: The powder was prepared using a citrate-nitrate one-step combustion method. 672.52 g (2 mol) Nd(NO3)3·6H2O and 868.44 g (2 mol) Ce(NO3)3·6H2O were weighed in a stoichiometric ratio of Nd2Ce2O7. All raw materials were dissolved in deionized water with heating and stirring to obtain a clear nitrate solution. 1260.84 g (6 mol) citric acid (CA) was weighed in a molar ratio of metal cation:citric acid (CA) = 1:1.5, and CA was dissolved in ultrapure water. The resulting mixed solution was uniformly stirred. 20% aqueous ammonia was slowly added dropwise to adjust the pH of the solution to 8. The mixture was heated at 70°C in a sealed, thermostatic water bath with continuous stirring for 12 hours to allow for complete complexation between CA and the metal cations. The plastic film was then removed and heating and stirring continued until the water evaporated, forming a viscous, brown gel. The gel was heated in an electric furnace until it spontaneously combusted, forming a fluffy, pale yellow powder. The resulting product was then held at 550°C for 0.5 hours to remove any residual organic matter, and then calcined at 800°C for 3 hours to obtain a nano-sized NCO phase powder.

[0074] S2: Preparation of NCO proton conductor coating-spin coating slurry: 0.7 g of the nanoscale NCO phase powder prepared in step S1 was dried and ground, and then mixed with a dispersion medium (a terpineol solution containing 1 wt% ethyl cellulose) in a mass ratio of 7:3. At the same time, 3 wt% of a binder (polyvinyl butyral, PVB) and 3 wt% of a surfactant (polyethylene glycol PEG) were added. The mixture was mixed at 500 rpm on a ball mill for 12 hours, followed by 40 minutes of ultrasonic dispersion treatment to further eliminate agglomerations.

[0075] S3: Preparation of the PCEC fuel electrode support: 0.6g of NiO, 0.4g of the nano-NCO phase powder prepared in step S1, and 0.1g of nano-graphite powder were placed in a ball mill and wet-milled with ethanol. Milling was performed at 400 rpm for 12 hours to thoroughly mix the mixture to obtain a fuel electrode powder. 0.30g of the fuel electrode powder was slowly poured into a 13mm diameter circular mold, gently shaken to spread it flat within the mold, and lightly pre-pressed. The powder was then co-pressed on a manual tablet press, maintaining an axial pressure of 250 MPa for 3 minutes. The resulting fuel electrode support green body was placed in a high-temperature resistance furnace and heated to 1000°C in air at a rate of 5°C / min for 1 hour. The temperature was then decreased to 800°C at a rate of 3°C / min. The furnace was then turned off and cooled to room temperature.

[0076] S4: Electrolyte Interface Construction: First, the heat-treated fuel electrode support prepared in step S3 was placed in a vacuum spin coater. Using a micropipette, 50 μL of the NCO proton conductor slurry prepared in step S2 was applied to the heat-treated fuel electrode support surface. The spin coating speed was controlled at 1500 rpm with an acceleration of 300 rpm / s for 20 seconds. Once the NCO proton conductor slurry was evenly distributed on the surface, the acceleration was increased from 300 rpm / s to 5000 rpm and maintained for 60 seconds to rapidly form a thin film. After drying at 80°C for 2 hours, the above operation was repeated twice to form a uniform NCO proton conductor coating. After spin coating, the coating was debonded at 600°C for 2 hours. The obtained half electrolytic cell (NiO-NCO / NCO) was placed in a high-temperature resistance furnace, and heated to 1100°C at a rate of 5°C / min in air atmosphere and kept at this temperature for 1 hour, then heated to 1450°C at a rate of 3°C / min and kept at this temperature for 5 hours to completely sinter the electrolyte, then cooled to 1200°C at a rate of 2°C / min and kept at this temperature for 1 hour, and finally cooled to 800°C at a rate of 3°C / min, then turned off the power and cooled to room temperature with the furnace. Figure 3 As mentioned above, the thickness is 5.21 μm.

[0077] The products obtained in Example 1 and Comparative Examples 1-2 were subjected to performance tests as follows:

[0078] (1) Morphology observation

[0079] The morphology of the semi-electrolytic cells prepared in Example 1 and Comparative Examples 1-2 was observed using SEM. Figure 1 The BaZr prepared in Example 1 0.1 Ce 0.8 Y 0.1 O 3-δ Cross-sectional SEM image of the / Nd2Ce2O7 heterogeneous electrolyte on the porous fuel electrode. Figure 1 It can be seen that the upper region is a dense Nd2Ce2O7 film, which is the main anti-water vapor layer and shows a dense microstructure. The middle layer is BaZr 0.1 Ce 0.8 Y 0.1 O 3-δ , providing good proton conductivity at medium temperature, with an overall thickness of 5.26μm.

[0080] Figure 2 BaZr prepared in Comparative Example 1 0.1 Ce 0.8 Y 0.1 O 3-δ Cross-sectional SEM image of the electrolyte on the porous fuel electrode. The electrolyte layer contains only BaZr 0.1 Ce 0.8 Y 0.1 O 3-δ Proton conductor. Figure 2 In the dense BaZr 0.1 Ce 0.8 Y 0.1 O 3-δ The electrolyte layer evenly covers the surface of the fuel electrode and has a thickness of about 5.17 μm.

[0081] Figure 3 This is a cross-sectional SEM image of the Nd2Ce2O7 electrolyte on the porous fuel electrode prepared in Comparative Example 2. The electrolyte layer contains only Nd2Ce2O7 proton conductor. Figure 3 The medium-density Nd2Ce2O7 film serves as the electrolyte layer, evenly covering the surface of the fuel electrode, with a thickness measured to be 5.21 μm.

[0082] It can be seen that the present invention can be used to prepare a dense electrolyte layer of 5 μm, and the electrolyte thickness of the embodiment and the comparative example is basically the same, thereby eliminating the influence of thickness on the open circuit voltage.

[0083] (2) Electrochemical performance test

[0084] The half electrolytic cell of Example 1 and Comparative Example 1-2 was coated with La 0.6 Sr 0.4 Co 0.2 Fe0.8 O 3-δ The slurry (purchased from Ningbo Suofer Energy Technology Co., Ltd.) is used as the air electrode, with an effective area of ​​0.28cm 2 , followed by electrochemical performance testing. The specific performance testing method is as follows:

[0085] Open-circuit voltage and power density testing: Using the two-terminal method, silver paste is evenly applied to the cathode side. The electrolyte sheet to be tested is placed in a box furnace and heated in air at 3°C ​​per minute to 400°C. After holding for 2 hours, the furnace is closed and cooled to room temperature. Φ0.2mm silver wires are bonded to both surfaces of the sample using conductive silver paste to create a two-electrode system. This is then connected and secured to the electrode wires of the electrochemical workstation. The open-circuit voltage and current-power density (IP) curve of the sample are measured using the electrochemical workstation.

[0086] The test conditions are as follows: the fuel gas is pure hydrogen (the H2 flow rate is adjusted to 40 mL / min) and the test temperature is 650°C.

[0087] Table 1 Electrochemical performance of Example 1 and Comparative Examples 1 and 2

[0088] Open circuit voltage Power density Example 1 1.07V 1.05W Comparative Example 1 0.98V 0.87W Comparative Example 2 0.82V 0.64W

[0089] Combined from Table 1 Figure 1-3 It can be seen that the BaZr 0.1 Ce 0.8 Y 0.1 O 3-δ The heterogeneous structure of / Nd2Ce2O7 shows significant interface advantages. Nd2Ce2O7 as the top layer provides excellent resistance to water vapor penetration, reducing the corrosion of water vapor on the electrolyte under high temperature environment and ensuring long-term stable operation. At the same time, its high density significantly reduces the gas cross-permeation phenomenon and reduces the impact of reverse diffusion on battery performance. The middle BaZr 0.1 Ce 0.8 Y 0.1 O 3-δ The layer provides good proton conductivity in the medium temperature region, significantly reduces the ohmic impedance, and optimizes the overall electrochemical performance. From the open circuit voltage test results, it can be seen that the present invention utilizes the migration characteristics of the Ba element during the preparation process to generate a nano-scale electron blocking layer in situ at the contact interface between the two, effectively preventing the Nd2Ce2O7 electrolyte from being blocked by Ce. 4+ Reduced to trivalent Ce 3+ The internal short circuit caused by the n-type electronic conductivity, the open circuit voltage at 650℃ is 0.82V (Nd2Ce2O7), 0.98V (BaZr 0.1 Ce 0.8 Y 0.1 O 3-δ) increased to 1.07V (BaZr 0.1 Ce 0.8 Y 0.1 O 3-δ / Nd2Ce2O7). The power density is 0.64W (Nd2Ce2O7), 0.87W (BaZr 0.1 Ce 0.8 Y 0.1 O 3-δ ) increased to 1.05W(BaZr 0.1 Ce 0.8 Y 0.1 O 3-δ / Nd2Ce2O7).

[0090] (3) In-situ continuous hydrogenation and upgrading test of biomass pyrolysis gas

[0091] Use purchased camphor wood biomass pellets as the biomass raw material. Before upgrading, place the raw material in an oven at 150°C for drying and weigh it every 5 hours until the mass of the redwood biomass pellets no longer changes. The total drying time is 50 hours. The specific operation method is as follows:

[0092] In-situ continuous hydrogenation testing of biomass pyrolysis gas: A steam generator generated steam with a water content of 30%, with a mass flowmeter controlling the flow rate at 40 mL / min. This steam was introduced into the air electrode of the PCEC, where it came into full contact with both the air electrode and the electrolyte surface. The high humidity of 30% helps improve the hydrogen production efficiency of the water electrolysis reaction and promotes the hydrogenation reaction between oxygen-containing functional groups in the pyrolysis gas and hydrogen, thereby achieving efficient pyrolysis gas upgrading. An electrochemical workstation applied a 1.3V DC voltage to the PCEC to drive the electrochemical reaction. Camphorwood biomass pellets were pyrolyzed in a fast pyrolysis furnace (heating rate >300°C / s to 600°C, dwelling for 1s) and then introduced into the PCEC fuel electrode without cooling. The fuel electrode gas products were collected and analyzed using gas chromatography-mass spectrometry (GC-MS). The current-voltage curve was monitored using an electrochemical workstation to determine the stability of the high-humidity in-situ continuous hydrogenation of biomass pyrolysis gas.

[0093] Table 2 Electrolytic performance of Example 1 and Comparative Example 1 after 65 hours of stabilization in high humidity environment

[0094] Current density <![CDATA[H2 production]]> Example 1 <![CDATA[1.45A cm -2 ]]> <![CDATA[817.5mL h -1 cm -2 ]]> Comparative Example 1 <![CDATA[1.13A cm -2 ]]> <![CDATA[586.5mL h -1 cm -2 ]]>

[0095] From the data in Table 2, it can be seen that the current density of Example 1 reaches 1.45 A·cm -2 , significantly higher than 1.13A·cm in Comparative Example 1 -2 At the same time, the hydrogen production in Example 1 was 817.5 mL·h -1 cm -2In contrast, the comparative example 1 was only 586.5 mL·h -1 cm -2 , showing obvious advantages in hydrogen production.

[0096] Table 3 Calorific value and stability parameters of Example 1 and Comparative Example 1 after hydrogenation in high humidity environment for 65 hours

[0097]

[0098] Table 3 compares the calorific value and stability parameters of the products of Example 1 and Comparative Example 1 after 65 hours of continuous hydrogenation and upgrading in a high humidity environment (30% water vapor). As can be seen from the data, Example 1 has a high calorific value of 65.2 MJ / kg and a low calorific value of 50.3 MJ / kg, while Comparative Example 1 has a high calorific value and low calorific value of only 12.5 MJ / kg and 13.7 MJ / kg, respectively, significantly lower than Example 1. Furthermore, the oxygen value of Example 1 is only 9.8%, while that of Comparative Example 1 is as high as 35.5%, indicating that Example 1 has a more pronounced deoxygenation effect. Furthermore, the viscosity and oxygen content of the products also show a significant difference. Example 1 has a viscosity of 3.9 cP and an oxygen content of 2.5%. In comparison, Comparative Example 1 has a viscosity of 20.3 cP and an oxygen content of 70.5%, indicating that the product of Comparative Example 1 is more viscous and rich in oxidizing substances. This difference is mainly attributed to the fact that the NiO-BZCY / BZCY / NCO structure of Example 1 is a synergistic protective structure that couples the high water resistance of NCO with the high-temperature preparation element diffusion characteristics of Ba. In a high-humidity environment, the presence of water vapor will accelerate the hydrolysis reaction of traditional proton conductors to generate carbonates or hydroxides, thereby causing electrolyte degradation, decreased conductivity, and seriously affecting the efficiency of hydrogenation quality improvement. The Nd2Ce2O7 layer in Example 1 exhibits a good shielding effect on water vapor, avoiding direct contact with water vapor, reducing the occurrence of side reactions, and ensuring the efficient migration of protons. This stable electrolyte environment effectively improves the efficiency of hydrogen generation, significantly reduces the oxygen content and viscosity of the product, and ultimately exhibits a higher calorific value and better stability. Therefore, the stability and hydrogenation efficiency of Example 1 in a high-humidity environment are significantly better than those of Comparative Example 1, showing stronger potential for industrial application.

[0099] Figure 4 The long-term stability test results of the electrolytic cells with BZCY and BZCY / NCO electrolyte structures prepared in Example 1 and Comparative Example 1 for in-situ hydrogenation of biomass pyrolysis gas at 650°C, 1.3V DC voltage, and high humidity are shown. Figure 4 The results show that BaZr 0.1 Ce 0.8 Y 0.1 O 3-δThe electrolytic cell with the heterogeneous interface of biomass / Nd2Ce2O7 maintained a stable current density output during 450 hours of continuous operation, demonstrating excellent electrochemical stability and resistance to water vapor corrosion, providing a reliable strategy for efficient electrochemical hydrogenation of biomass pyrolysis gas.

[0100] The basic process, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A proton conductor electrolyte of PCEC, characterized in that The proton conductor electrolyte comprises a PCEC fuel electrode support and a BZCY proton conductor layer and an NCO proton conductor layer sequentially arranged on its surface, wherein the contact surface of the BZCY proton conductor layer and the NCO proton conductor layer constitutes an in-situ protected interface structure of NiO-BZCY / BZCY / NCO, the material of the NCO proton conductor layer is A2B2O7 type fluorite structure oxide Nd2Ce2O7, and the material of the BZCY proton conductor layer includes ABO3 type perovskite structure oxide BaZr x Ce y Y 1-x-y O 3-δ (BZCY), 0≤x+y+z≤1, y≠0.

2. A proton conductor electrolyte for PCEC according to claim 1, characterized in that: The in-situ protected interface structure of NiO-BZCY / BZCY / NCO couples the high water resistance of NCO with the element diffusion characteristics of Ba prepared at high temperature to form a protective structure with excellent interface synergistic effect. The thickness of the BZCY proton conductor layer is 2.5-3 μm, and the thickness of the NCO proton conductor layer is 2-2.5 μm.

3. A method for preparing a proton conductor electrolyte of PCEC according to claim 1, characterized in that: The following steps are involved: S1: Preparation of NCO proton conductor powder: Preparation is carried out by a citrate-nitrate one-step combustion method, wherein soluble neodymium salt and cerium salt are deionized in water to obtain a clear salt solution; citric acid is dissolved in water to obtain an acid solution; the salt solution and the acid solution are uniformly stirred and mixed, the pH is adjusted to 7-8, and a closed reaction is carried out at a constant temperature to allow the citric acid to fully complex with the metal cations, evaporate to form a gel, and spontaneously combust to form a powder, which is then calcined to obtain a nano-scale NCO phase powder; S2: Preparation of BZCY proton conductor powder: Cerium salt, zirconium salt, barium salt, and yttrium salt are sequentially dissolved in water, the resulting salt solution is poured into a citric acid solution, and then ethylene glycol is added to the solution to adjust the pH of the solution to 8-9 until the flocs in the solution disappear. The solution is heated at a constant temperature to form a viscous white gel; the gel is rapidly heated, dried, and vigorously burned to obtain a white-yellow powder, which is crushed and calcined at a high temperature to obtain BZCY proton conductor powder; S3: Preparation of NCO proton conductor slurry: The nano-scale NCO phase powder prepared in step S1 is dried and ground, then mixed with a dispersion medium, and a binder and a surfactant are added, mixed in a ball mill, and then subjected to ultrasonic dispersion treatment to further eliminate agglomerates; S4: Preparation of BZCY proton conductor slurry: The BZCY proton conductor powder prepared in step S2 is dried and ground, then mixed with a dispersion medium, and a binder and a surfactant are added, mixed on a ball mill, and then ultrasonically dispersed to further eliminate agglomerates; S5: Preparation of PCEC fuel electrode support: NiO, BZCY proton conductor powder obtained in step S2, and nanographite powder are placed in a ball mill and wet-milled with ethanol to mix them thoroughly to obtain fuel electrode powder; the fuel electrode powder is compression molded to obtain a fuel electrode support green body, and the PCEC fuel electrode support is obtained after heat treatment; S6: Electrolyte heterogeneous interface construction: the fuel electrode support prepared in step S5 is placed in a vacuum spin coater, and the BZCY proton conductor slurry prepared in step S4 is evenly coated on its surface to form a uniform BZCY proton conductor coating, and then the NCO proton conductor slurry prepared in step S3 is spin-coated on the surface of the BZCY proton conductor to form a uniform BZCY / NCO proton conductor coating to obtain a semi-electrolytic cell NiO-BZCY / BZCY / NCO, which is placed in a high-temperature resistance furnace and heated in air atmosphere. The temperature was raised to 1100-1200°C at a rate of 4-6°C / min and kept at this temperature for 0.5-1.5h. Subsequently, the temperature was raised to 1400-1500°C at a rate of 2-4°C / min and kept at this temperature for 4-6h to completely sinter the electrolyte into a dense state. The temperature was then lowered to 1100-1300°C at a rate of 1-3°C / min and kept at this temperature for 0.5-1.5h. Finally, the temperature was lowered to 750-850°C at a rate of 2-4°C / min, the power was turned off, and the furnace was cooled to room temperature to obtain an electrolyte with a BZCY / NCO heterogeneous interface.

4. The method for preparing a proton conductor electrolyte of PCEC according to claim 2, characterized in that: In step S1, the neodymium salt is Nd(NO3)3·6H2O, and the cerium salt is Ce(NO3)3·6H2O; the neodymium salt and the cerium salt are weighed according to a stoichiometric ratio of a chemical composition of Nd2Ce2O7; The amount of citric acid added is such that the molar ratio of the metal cation to the citric acid in the salt solution is 1:1.5-2; Use ammonia water with a mass concentration of 15% to 20% to adjust the pH value; The temperature of the constant temperature heating closed reaction is 65-75°C. The calcination is to calcine the powder formed by spontaneous combustion at 500-600°C for 0.1-1h to remove residual organic matter in the powder, and then calcine at 750-850°C for 2-4 hours to obtain nano-scale NCO phase powder.

5. The method for preparing a proton conductor electrolyte of PCEC according to claim 2, characterized in that: In step S2, the barium salt is Ba(NO3)2, the zirconium salt is Zr(NO3)4·5H2O, and the cerium salt is H8CeN8O 18 , yttrium salt, cerium salt, zirconium salt, barium salt, yttrium salt according to BaZr x Ce y Y 1-x-y O 3-δ Weigh the stoichiometric ratio; The molar ratio of the metal cation to the ethylene glycol and citric acid in the salt solution is 1:1.5-2:1.5-2; Use ammonia water with a mass concentration of 15%-20% to adjust the pH value; The constant temperature heating reaction temperature is 75-85°C and the time is 7-8h; The rapid heating of the gel is to heat it to 250-350° C., dry it into a porous solid material, and then burn it violently to obtain a white-yellow powder. The calcination is to keep it at 1100-1300° C. for 4-6 hours and then cool it with the furnace.

6. The method for preparing a proton conductor electrolyte of PCEC according to claim 2, characterized in that: In step S3, the mass ratio of the nano-scale NCO phase powder to the dispersion medium is 5 to 7:4; Based on the total weight of the nano-scale NCO phase powder and the dispersion medium as 100%, the added amount of the binder is 3-4%; the added amount of the surfactant is 5-7%; The dispersion medium is a terpineol solution containing 1-2 wt% ethyl cellulose; The binder is polyvinyl butyral; The surfactant is polyethylene glycol; The rotation speed of the ball mill is 450-500 rpm; the ball milling time is 10-14 hours; and the ultrasonic dispersion time is 30-40 minutes.

7. The method for preparing a proton conductor electrolyte of PCEC according to claim 2, characterized in that: In step S4, the mass ratio of BZCY proton conductor powder to dispersion medium is 6 to 8:3; Based on the total weight of the BZCY proton conductor powder and the dispersion medium as 100%, the added amount of the binder is 2-3%; the added amount of the surfactant is 3-5%; The dispersion medium is a terpineol solution containing 1-2 wt% ethyl cellulose; The binder is polyvinyl butyral; The surfactant is polyethylene glycol; The rotation speed of the ball mill is 450-500 rpm, the ball milling time is 10-14 hours, and the ultrasonic dispersion time is 30-40 minutes.

8. The method for preparing a proton conductor electrolyte of PCEC according to claim 2, characterized in that: In step S5, the mass ratio of NiO, the BZCY proton conductor powder obtained in step S2, and the nano-graphite powder is 6:4:1, the speed of the ball mill is 350-400 rpm, and the ball milling time is 10-14 hours; the axial pressing pressure of the fuel electrode powder molding is 250-300 MPa, and the holding time is 2-4 minutes; the fuel electrode support green body is heat treated in an air atmosphere at a heating rate of 4-6°C / min to 900-1100°C, holding for 0.5-1.5 hours, and then cooled to 750-850°C at a cooling rate of 2-4°C / min, and then the power is turned off and the furnace is cooled to room temperature.

9. The method for preparing a proton conductor electrolyte of PCEC according to claim 2, characterized in that: In step S6, the BZCY proton conductor slurry is coated on the surface of the fuel electrode support by spin coating. The specific operation is as follows: the BZCY proton conductor slurry is spin-coated on the surface of the fuel electrode support, the spin coating speed is controlled at 1500-2000 rpm, the acceleration is 250-350 rpm / s, and it is maintained for 15-25 seconds; then the vacuum spin coater is accelerated from 250-350 rpm / s to 5000-5500 rpm and maintained for 55-65 seconds for rapid thin film processing, and after drying at 75-85°C for 1-3 hours, the above operation is repeated; The debinding process is to heat the temperature to 550-650°C at a heating rate of 1-2°C / min and perform debinding for 1-3 hours; The NCO proton conductor slurry is spin-coated on the surface of the BZCY proton conductor by the following method: the fuel electrode support covered with the BZCY proton conductor coating is debonded and placed back in a vacuum spin coater, the spin coating speed is controlled at 2000-2500 rpm, the acceleration is 450-550 rpm / s, and the speed is maintained for 25-35 seconds; then the vacuum spin coater is accelerated from 450-550 rpm / s to 6000-6500 rpm and the speed is maintained for 45-55 seconds for rapid thin film processing; The thickness of the BZCY / NCO heterojunction interface of the obtained electrolyte is 4-5 μm.

10. An application of a proton conductor electrolyte of PCEC as claimed in claim 1, characterized in that: The proton conductor electrolyte PCEC is applied to the continuous in-situ hydrogenation upgrading of biomass pyrolysis gas in a high-humidity environment.

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