Application of voltage-regulated self-cleaning solid oxide batteries in methane dry reforming

Abstract

This invention relates to a method for applying a voltage-regulated self-cleaning solid oxide battery in methane dry reforming. The solid oxide battery has a perovskite precursor material impregnated within its anode support. Under a reducing atmosphere, metallic Ni nanoparticles precipitate in situ and are spatially confined and anchored to the perovskite surface, forming an exogenous Ni-perovskite active interface. The application method includes: introducing a mixed gas containing methane and carbon dioxide into multiple internal channels under a high-temperature, oxygen-free or micro-oxygen environment; introducing air or oxygen-containing gas into the cathode reaction layer side; connecting the battery to an adjustable load or electrochemical workstation via an external circuit current collector; and applying a bias voltage to the battery to allow it to undergo methane dry reforming at a voltage below the open-circuit voltage. This invention utilizes an electric field to regulate interfacial oxygen renewal to eliminate carbon species in situ, solving the problems of carbon buildup and performance degradation in existing methods.

Description

Technical Field

[0001] This invention relates to the field of solid oxide battery technology, and more specifically to the application of a voltage-regulated self-cleaning solid oxide battery in methane dry reforming. Background Technology

[0002] Dry reforming of methane (DRM, CH4 + CO2 → 2CO + 2H2) can simultaneously convert two major greenhouse gases, methane and carbon dioxide, into valuable syngas. Combining solid oxide battery (SOC) technology with dry reforming of methane not only activates the co-reactants in a high-temperature environment but also achieves efficient electrical energy output while converting chemical energy and producing syngas suitable for the Fischer-Tropsch reaction. Existing solid oxide batteries for dry reforming of methane (such as conventional tubular oxygen-ion conductor batteries) mostly use traditional non-precious metal nickel-based cermets (such as NiO-YSZ) as the anode catalyst material.

[0003] During the long-term dry reforming process, this type of traditional battery faces two major challenges: First, the methane cracking rate is much faster than the carbon elimination rate driven by carbon dioxide, leading to severe side reactions and carbon deposition on the surface of non-noble metal Ni, covering the active sites. Second, under high-temperature operation, physically mixed metallic Ni nanoparticles are prone to sintering and growth due to their high surface energy, resulting in severe degradation of the three-phase interface (TPB) and a sharp decline in battery performance. In addition, the traditional single-channel cylindrical battery structure has a long gas diffusion path and a small effective electrode reaction specific surface area, which limits gas mass transfer kinetics and overall energy conversion efficiency.

[0004] Therefore, designing a solid oxide battery that combines efficient mass transfer structure with the ability to fundamentally address carbon deposition and sintering at the catalyst interface micro-kinetics is currently the core bottleneck for efficient electrochemical conversion of greenhouse gases. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a voltage-regulated self-cleaning solid oxide battery for use in methane dry reforming. By utilizing an electric field to regulate interfacial oxygen renewal, carbon species are eliminated in situ, achieving stable anti-carbon deposition operation and efficient power output in long-term methane dry reforming reactions. This solves the technical problems of easy carbon deposition and performance degradation of batteries caused by long-term operation in existing methane dry reforming reactions.

[0006] The technical solution adopted in this invention is as follows: This invention provides a method for applying a voltage-regulated self-cleaning solid oxide battery in methane dry reforming. The solid oxide battery includes, from the inside out, a porous anode support, a dense oxygen ion conductor electrolyte layer, a barrier layer, and a cathode reaction layer. The porous anode support has multiple internal channels formed inside, which are modified with a catalyst. The modification of the catalyst includes impregnating the porous anode support with a perovskite precursor material Pr. 0.5 Ba 0.5 Mn 0.85 Ni 0.15 O 3-δ Under the induction of a reducing atmosphere, metallic Ni nanoparticles are precipitated in situ and spatially confined and anchored on the perovskite surface, forming an exogenous Ni-perovskite active interface. The application method includes: In a high-temperature oxygen-free or micro-oxygen environment, a mixed gas containing methane and carbon dioxide is introduced into the multiple internal channels, and air or oxygen-containing gas is introduced into the cathode reaction layer side. The battery is connected to an adjustable load or electrochemical workstation via an external circuit current collector. A bias voltage is applied to the battery, allowing it to undergo methane dry reforming at a voltage lower than the open circuit voltage. The exogenous Ni-perovskite active interface undergoes dynamic oxygen renewal through the regulation of an external electric field. This process is used to eliminate carbon species precursors generated by methane dissociation in situ, achieving anti-carbon deposition operation and outputting electrical energy. The bias voltage is a negative offset relative to the open circuit voltage.

[0007] The preferred technical solution is: The bias voltage ΔV is less than the open-circuit voltage by no more than 1V, i.e., -1.0 V ≤ ΔV < 0 V.

[0008] The operating temperature for the methane reforming reaction is 600–800°C.

[0009] The mixed gas containing methane and carbon dioxide includes methane, carbon dioxide, and a carrier gas, with a volume ratio of 2:2:1.

[0010] The total flow rate of the mixed gas is 30-100 ml / min.

[0011] The perovskite precursor material Pr 0.5 Ba 0.5 Mn 0.85 Ni 0.15 O 3-δ The amount of precursor adhering to the surface of the channel within the porous anode support is 5 wt%.

[0012] The preparation and modification of the catalyst include: High-purity praseodymium nitrate, barium nitrate, manganese nitrate, and nickel nitrate, along with citric acid monohydrate as a complexing agent, were weighed according to stoichiometric ratios and completely dissolved in deionized water. Then, ethylenediaminetetraacetic acid was added to prepare Pr. 0.5 Ba 0.5 Mn 0.85 Ni0.15 O 3-δ Precursor solution; Using vacuum-assisted impregnation, Pr 0.5 Ba 0.5 Mn 0.85 Ni 0.15 O 3-δ The precursor solution is introduced into the pores of the multi-channel porous anode support; after repeated impregnation and drying, it is heat-treated at 950-1100℃ to make Pr 0.5 Ba 0.5 Mn 0.85 Ni 0.15 O 3-δ The precursor is attached to the inner surface of the porous anode support; A reducing gas is introduced into the internal channel for in-situ reduction at high temperature, promoting the reduction of Pr. 0.5 Ba 0.5 Mn 0.85 Ni 0.15 O 3-δ Ni ions in the perovskite lattice migrate to the surface and precipitate in situ into uniform, spatially confined metallic Ni nanoparticles, thus constructing an exogenous Ni-perovskite active interface in situ.

[0013] Pr 0.5 Ba 0.5 Mn 0.85 Ni 0.15 O 3-δ The molar ratio of metal ions, citric acid, and ethylenediaminetetraacetic acid in the precursor solution is 1:2:1.

[0014] The porous anode support is made of NiO-YSZ porous ceramic material, the dense oxygen ion conductor electrolyte layer is made of YSZ, the barrier layer is made of GDC, and the cathode reaction layer is made of porous perovskite material LSCF.

[0015] The porous anode support is prepared by phase inversion assisted extrusion. The raw materials used in the preparation solution include NiO powder, YSZ powder, polyethylene glycol-30-dipolyhydroxystearate, N-methylpyrrolidone and binder, and the mass ratio is (90~110):(60~70):(0~2.5):(45~55):(10~20).

[0016] The technical solution of the present invention can achieve at least some of the following beneficial effects: This invention establishes an exogenous Ni-perovskite heterostructure interface formed by in-situ precipitated Ni nanoparticles and a perovskite matrix on the anode side of a multi-channel microtube solid oxide battery. This interface is coupled with tunable sub-OCV polarization—applying a bias voltage lower than the open-circuit voltage to operate the battery in a sub-open-circuit state—thus establishing an electric field-controlled self-cleaning mechanism of "active interface bias response—interfacial oxygen dynamic renewal—in-situ elimination of carbon species." The Ni-perovskite heterostructure interface and bias voltage regulation in this invention exhibit a synergistic effect. The in-situ precipitated Ni nanoparticles form a stable heterostructure interface with the perovskite matrix. This heterostructure interface not only possesses active sites for metallic Ni, but the perovskite matrix also exhibits adjustable lattice oxygen, oxygen vacancies, and a strong interfacial oxygen exchange capacity. When the battery is in a sub-open-circuit voltage polarization state, the local electric field and oxygen ion flux can regulate the oxygen vacancy concentration, lattice oxygen migration rate, and local oxidation potential at the Ni-perovskite heterostructure interface, causing continuous oxygen migration, release, and replenishment at the interface, forming a dynamic oxygen renewal process. This dynamic oxygen renewal can promptly provide active oxygen species to the Ni active sites and surrounding interface after methane dissociation to generate carbon species precursors. This allows the carbon species precursors to be oxidized and eliminated in situ before the formation of stable carbon nuclei, thereby inhibiting the nucleation, growth, and continuous carbon layer formation of carbon nuclei, achieving real-time self-cleaning of the anode active interface. In other words, the Ni-perovskite heterostructure interface constitutes a response carrier for bias voltage regulation, and the applied bias voltage determines the oxygen renewal intensity and carbon elimination capacity of this interface.

[0017] Traditional Ni-YSZ electrodes are mainly composed of metallic Ni and a relatively stable YSZ electrolyte phase, lacking a perovskite lattice oxygen system capable of participating in rapid oxygen exchange. Even with appropriate bias voltage, it is difficult to form a bias-responsive oxygen renewal mechanism comparable to that of the Ni-perovskite heterointerface under the same bias voltage conditions. Furthermore, for the Ni-perovskite heterointerface, without a suitable bias voltage, its interfacial oxygen renewal rate may be insufficient to continuously balance the carbon species generated by high-temperature methane cracking. Experimental results show that combining a bias-responsive Ni-perovskite heterointerface with sub-open-circuit voltage regulation is beneficial for continuously regulating the kinetic balance between carbon formation and carbon elimination, allowing carbon species to be removed in time before nucleation and deposition. Therefore, this invention can suppress the rapid carbon deposition and deactivation that occurs in traditional Ni-based anodes during methane dry reforming without relying on noble metal catalysts, maintaining high cleanliness and reactivity of the anode active interface during long-term high-temperature operation, achieving stable and continuous anti-carbon deposition methane dry reforming operation.

[0018] This invention allows for the active control of the methane dry reforming process by applying different sub-open-circuit voltages. Different bias voltages correspond to different local electric field strengths and oxygen ion transport fluxes, thereby adjusting the oxygen vacancy concentration, surface oxygen coverage, and local oxidation potential at the Ni-perovskite heterointerface, and altering the relative rates of methane activation, carbon dioxide activation, carbon species oxidation, and the reverse water-gas shift side reaction. Simultaneously, by adjusting the applied bias voltage, the methane conversion rate, carbon dioxide conversion rate, syngas generation rate, H2 / CO ratio, and battery output performance can be controlled under different operating temperatures and feed conditions. When the bias voltage is low or inappropriate polarization is not achieved, the supply of active oxygen at the interface may be insufficient, and the rate of carbon species generation from methane cracking may exceed the carbon elimination rate, easily leading to carbon deposition. As the bias voltage is adjusted to a suitable range, the interface oxygen renewal rate increases, and carbon generation and carbon elimination can reach a dynamic balance. By limiting an appropriate bias voltage window, excessive oxidation of reactants or syngas products caused by excessive oxygen flux can be avoided. Therefore, this invention does not rely solely on high temperature or catalyst composition to passively control the dry reforming reaction, but rather utilizes bias voltage as an independent, continuous, and adjustable operating parameter to actively regulate the activity, product composition, and carbon balance of the dry reforming reaction.

[0019] Furthermore, the in-situ precipitated Ni nanoparticles used in this invention are confined and anchored by the perovskite lattice, which helps reduce the tendency of Ni particles to migrate, agglomerate, and sinter at high temperatures, maintaining a stable Ni-perovskite heterostructure and effective reaction sites. The multi-channel microtube structure can increase the effective reaction area per unit volume, shorten the diffusion path of reactant gases in the porous anode, and improve the mass transfer conditions of methane, carbon dioxide, and generated gases.

[0020] Therefore, this invention achieves power output while performing methane dry reforming and producing carbon monoxide and hydrogen through the combined effects of bias-tunable interfacial oxygen renewal, in-situ precipitation of Ni-perovskite heterostructure, and multi-channel mass transfer structure. It also has reaction control capability, long-term anti-carbon deposition capability, high-temperature structural stability, and syngas-electricity synergistic production capability.

[0021] Other features and advantages of the invention will be set forth in the following description or may be learned by practicing the invention. Attached Figure Description

[0022] Figure 1 This is a flowchart of the application method in an embodiment of the present invention.

[0023] Figure 2 This is a schematic diagram of the main structure of a solid oxide battery according to an embodiment of the present invention.

[0024] Figure 3This is a comparison of the dry reforming reaction effects of the fuel cell of Example 3 of the present invention and its comparative example under a bias voltage of 0 to -1 V relative to the open circuit voltage.

[0025] Figure 4 This is a schematic diagram showing the results of the methane dry reforming reaction activity and syngas control capability of the fuel cell under different bias voltage regulation in Example 3 of the present invention.

[0026] Figure 5 The image shows the SEM images of the fuel cell of Example 4 of the present invention and its comparative example after a bias voltage stability test.

[0027] Explanation of reference numerals in the attached figures: 1. Porous anode support; 2. Inner channel; 3. Catalyst impregnation interface; 4. Dense oxygen ion conductor electrolyte layer and barrier layer; 5. Cathode reaction layer. Detailed Implementation

[0028] The specific embodiments of the present invention are described below with reference to the accompanying drawings.

[0029] Example 1 See Figure 2 This embodiment provides a solid oxide battery, the main body of which includes, from the inside out, a porous anode support 1, a dense oxygen ion conductor electrolyte layer and a barrier layer 4, and a cathode reaction layer 5; the porous anode support 1 has multiple independent internal channels 2 formed inside, each internal channel 2 extending axially to form a gas chamber for reaction; during the battery fabrication process, the porous anode support 1 is impregnated with a perovskite precursor material Pr 0.5 Ba 0.5 Mn 0.85 Ni 0.15 O 3-δ (PBMN), under the induction of a reducing atmosphere, metallic Ni nanoparticles are precipitated in situ and spatially confined and anchored on the perovskite surface, forming exsolved Ni-perovskite interfaces; wherein PBMN at least covers the catalyst impregnation interface 3.

[0030] Specifically, the porous anode support 1 is made of NiO-YSZ porous ceramic material, the dense oxygen ion conductor electrolyte layer is made of YSZ, the barrier layer is made of GDC, and the cathode reaction layer 5 is made of porous perovskite material LSCF. YSZ is yttrium-stabilized zirconium oxide (ZrO2). 1-x Y x O 2-δ GDC is gadolinium-doped cerium oxide (Ce). 0.9 Gd 0.1 O 1.95 ); LSCF is La 0.6 Sr 0.4 Co0.2 Fe 0.8 O 3-δ .

[0031] As a preferred embodiment, the perovskite precursor material Pr 0.5 Ba 0.5 Mn 0.85 Ni 0.15 O 3-δ The amount of precursor adhering to the surface of the channel within the porous anode support is 5 wt%.

[0032] As a preferred method, the porous anode support 1 is prepared by phase inversion assisted extrusion. The raw materials used in the preparation solution include NiO powder, YSZ powder, polyethylene glycol-30-dipolyhydroxystearate, N-methylpyrrolidone and binder, and the mass ratio is (90~110):(60~70):(0~2.5):(45~55):(10~20).

[0033] As a preferred approach, there are four independent internal channels 2 that run parallel through the entire anode support 1 to maximize the electrode reaction surface area and shorten the gas mass transfer path.

[0034] As a preferred embodiment, the dense oxygen ion conductor electrolyte layer, the barrier layer 4, and the cathode reaction layer 5 are sequentially deposited on the outer surface of the multi-channel porous anode support 1 by means of immersion or brushing.

[0035] Specifically, the reducing atmosphere is a 5-10% H2 / Ar mixture or an in-situ reducing atmosphere for dry methane reforming.

[0036] Example 2 This embodiment provides a method for preparing the solid oxide battery described in Embodiment 1, comprising: Porous anode supports were prepared using phase inversion-assisted extrusion. NiO powder, YSZ powder, or a mixture of YSZ powder and polyethylene glycol-30-dipolyhydroxystearate, N-methylpyrrolidone, and binder are mixed in a certain proportion and then ball-milled to prepare a film liquid. The vacuum-treated film liquid and coagulant are extruded using a multi-channel spinneret to form a precursor. The precursor is sintered to form the fuel electrode substrate. The mass ratio of NiO powder, YSZ powder, polyethylene glycol-30-dipolyhydroxystearate, N-methylpyrrolidone, and binder is (90~110):(60~70):(0~2.5):(45~55):(10~20).

[0037] Constructing an electrolyte layer and a barrier layer: 20g of YSZ, 2g of PVB, and 1g of PEG powder were added to 100g of anhydrous ethanol and ball-milled for 24 hours to obtain a YSZ electrolyte slurry. 20g of GDC, 2g of PVB, and 1g of PEG powder were added to 100g of anhydrous ethanol and ball-milled for 24 hours to obtain a GDC barrier layer slurry. A dense oxygen ion conductor electrolyte layer slurry (YSZ) and a barrier layer (GDC) slurry were sequentially deposited on the outer surface of the porous anode support tube by dip-coating. The entire tubular preform was then placed in a high-temperature furnace and co-sintered at 1350~1450℃ for 4~6 hours to obtain a multichannel microtube half-cell with a dense electrolyte layer.

[0038] PBMN, a perovskite precursor material with in-situ precipitation characteristics, was prepared using an improved sol-gel method. Accurately weigh high-purity praseodymium nitrate (Pr(NO3)3·6H2O), barium nitrate (Ba(NO3)2), manganese nitrate (Mn(NO3)2·4H2O), and nickel nitrate (Ni(NO3)2·6H2O), along with citric acid monohydrate (CA) as a complexing agent, according to stoichiometric ratios, and completely dissolve them in deionized water; then add a quantitative amount of EDTA according to a reasonable molar ratio of metal ions to citric acid and ethylenediaminetetraacetic acid (EDTA) (e.g., 1:2:1) to prepare a PBMN precursor solution with a total metal ion concentration of 1 mol·L-1; A PBMN precursor solution was introduced into the pores of a multi-channel porous anode support and functional layer using a vacuum-assisted impregnation method. After repeated impregnation and drying, the solution was heat-treated at 950-1100℃ to allow the PBMN precursor to adhere to the inner surface of the porous anode support at a concentration of 5 wt%.

[0039] Cathode construction and integration: GDC, LSCF and ethylene glycol are ball-milled at a mass ratio of 5:5:6 for 24 hours to obtain a porous perovskite cathode material slurry. The porous perovskite cathode material slurry is then sprayed or dipped onto the outer surface of the barrier layer and calcined at 950~1050℃ for 2~3 hours to form a porous cathode reaction layer.

[0040] In-situ precipitation and activation: A reducing gas (such as an atmosphere containing H2) is introduced into the multi-channel tube, and in-situ reduction treatment is carried out at 850℃. This causes Ni ions in the PBMN perovskite lattice to migrate to the surface and precipitate in-situ into uniform, spatially confined metallic Ni nanoparticles, thereby constructing a highly stable, sintering-resistant exogenous Ni-perovskite active interface in situ. This completes the preparation of the main structure of the solid oxide battery.

[0041] Finally, airflow sealing connectors are provided at both ends of the solid oxide body, and current collectors made of silver paste are provided on both sides of the anode support and on the outside of the cathode reaction layer for the introduction of mixed gas, the export of reforming products and the conduction of current, in preparation for subsequent applications.

[0042] Example 3 See Figure 1 This embodiment provides a method for applying a voltage-regulated self-cleaning solid oxide battery in methane dry reforming. The solid oxide battery obtained in Example 2 is installed in a reforming test system to form a solid oxide fuel cell, and electrochemical methane dry reforming is performed, including: S1. In a high-temperature oxygen-free or micro-oxygen environment, a mixed gas containing methane and carbon dioxide is introduced into the plurality of internal channels, and air or oxygen-containing gas is introduced into the cathode reaction layer side.

[0043] Specifically, at a high temperature of 800℃, a mixture of CH4, CO2, and Ar (volume ratio 2:2:1) was introduced into multiple inner channels of the microtube, with the total flow rate controlled at 50 ml / min. -1 .

[0044] It is understood that in some other embodiments, the total flow rate or space velocity of the mixed gas is adjusted according to the battery volume; the operating temperature of the solid oxide battery is 600-800°C, specifically 650°C and above, preferably 700-800°C.

[0045] S2. Connect the battery to a DC power supply or electrochemical workstation via an external circuit current collector, apply a bias voltage to the battery, and perform methane dry reforming in a state below the open circuit voltage (i.e., sub-open circuit voltage state); the exogenous Ni-perovskite active interface is dynamically renewed by the regulation of the applied electric field, which is used to eliminate carbon species precursors generated by methane dissociation in situ, realize anti-carbon deposition operation and output electrical energy; the bias voltage is a negative offset relative to the open circuit voltage.

[0046] Preferably, the bias voltage ΔV is less than the open-circuit voltage by no more than 1V, i.e., -1.0 V ≤ ΔV < 0 V.

[0047] The specific principle of the methane reforming reaction is as follows: oxygen on the cathode side of the battery accepts electrons to generate oxygen ions. The oxygen ions are transported to the anode side through the dense oxygen ion conductor electrolyte layer and participate in the oxygen renewal and fuel electrochemical oxidation process in the exogenous Ni-perovskite active interface in the porous network of the inner channel and porous anode support. Methane and carbon dioxide undergo a dry reforming reaction on the anode side to generate carbon monoxide and hydrogen. The electrons generated during the reaction are output through the external circuit, thereby realizing the output of electrical energy while producing syngas.

[0048] In this embodiment, the battery output voltage or the applied bias voltage is kept below the open circuit voltage to achieve sub-OCV regulation. The generated microscopic local electric field is used to maintain the kinetic balance between carbon deposition and carbon elimination at the exogenous interface.

[0049] To test battery performance and reforming effects under different bias voltages, the applied bias voltages ΔV in this embodiment were 0V, -0.2V, -0.4V, -0.6V, -0.8V, and -1.0V relative to the open-circuit voltage (OCV). The test results are shown below. Figure 3 , Figure 4 .like Figure 3 As shown in Figure a, at 800℃, the CH4 conversion, CO2 conversion, product composition, and H2 / CO ratio of the solid oxide fuel cell all exhibit significant bias-dependent effects with changes in the applied bias voltage. This indicates that sub-open-circuit voltage polarization can effectively regulate the interfacial oxygen supply rate and local oxidation potential, thereby altering the methane dry reforming reaction pathway and its competitive relationship with the reverse water-gas shift side reaction. Particularly at 800℃, the catalyst-modified multichannel microtube solid oxide fuel cell achieved a CH4 conversion exceeding 99% and a CO2 conversion reaching 95.5% under -0.4 V (vs. OCV) conditions. The CO / H2 ratio at the outlet was close to 1, demonstrating superior reactivity and syngas control capabilities. Figure 4 As shown. By adjusting the applied potential, O can be further controlled. 2- Flux, enabling precise control of the H2 / CO ratio.

[0050] As a comparative example, a multi-channel solid oxide fuel cell without a precursor (the only difference from the cell in this embodiment is the absence of PBMN modification) was used, and bias control experiments were conducted under the same conditions. The test results are as follows: Figure 3 As shown in Figure b, the CH4 conversion rate of the unmodified Ni-YSZ battery remained relatively stable between 96% and 98% under different bias voltages, the CO2 conversion rate was approximately 83% to 89%, and the H2 / CO ratio was approximately 0.68 to 0.70, with minimal overall fluctuations and no significant bias voltage dependence. This indicates that for the unmodified electrode interface, applying a sub-open-circuit voltage alone cannot significantly alter the dry reforming reaction behavior, nor can it effectively and actively control the product composition and reaction pathway.

[0051] The above comparative results show that the PBMN-modified battery in this embodiment exhibits bias-dependent behavior. This dependence does not stem from general battery polarization effects, but rather from the specific response of the exogenous Ni-perovskite heterointerface to bias. At this heterointerface, bias can effectively regulate oxygen vacancy concentration, lattice oxygen migration, and local oxidation potential, inducing a dynamic oxygen renewal process, thereby achieving synergistic regulation of CH4 activation, CO2 activation, carbon species elimination, and product selectivity. In contrast, the unmodified Ni-YSZ battery lacks this type of bias-responsive heterointerface and therefore does not exhibit a significant bias-controlled effect.

[0052] Example 4 This embodiment provides a method for applying a voltage-regulated self-cleaning solid oxide battery in methane dry reforming. The solid oxide battery obtained in Example 2 is installed in a reforming test system to form a solid oxide fuel cell, and electrochemical methane dry reforming is performed. The difference from Example 3 is that, with all other steps and conditions being the same, the method is as follows: At a high temperature of 700℃, a mixture of CH4, CO2, and Ar (volume ratio 1:1:2) was introduced into multiple inner channels of the microtube, with the total flow rate controlled at 100 ml / min. -1 Apply a constant polarization current or bias voltage, with the bias voltage set to a constant -0.4V, to make the battery operate at a sub-open circuit voltage (-0.4V vs. OCV).

[0053] As a comparative example, a multichannel solid oxide fuel cell without the introduction of a precursor (the only difference from the battery in this embodiment is that it was not modified with PBMN) was used to conduct test experiments under the same conditions to evaluate the electrochemical methane dry reforming performance.

[0054] The SEM images of the anode after the stability test are as follows: Figure 5 As shown. Due to the real-time driving of the local micro-electric field to dynamically renew the oxygen at the exogenous Ni-perovskite interface, the voltage-regulated PBMN-modified multichannel microtube solid oxide fuel cell effectively balances and eliminates carbon species generated by methane dissociation. After 500 hours of continuous operation, as... Figure 5 As shown in Figure a, no obvious filamentous carbon or carbon deposition morphology was observed at the anode exogenous catalytic interface under the stated test conditions and test period, and the metallic Ni nanoparticles did not exhibit significant aggregation or sintering, maintaining highly stable battery performance. Figure 5 As shown in Figure b, the anode surface of the unmodified Ni-YSZ battery exhibits significant carbon buildup after 100 hours of continuous operation under sub-open circuit voltage conditions.

[0055] It will be understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for applying a voltage-regulated self-cleaning solid oxide battery in methane dry reforming, characterized in that, The solid oxide battery includes, from the inside out, a porous anode support, a dense oxygen ion conductor electrolyte layer, a barrier layer, and a cathode reaction layer; The porous anode support has multiple internal channels formed inside, which are modified with a catalyst. The modification of the catalyst includes impregnating the porous anode support with a perovskite precursor material Pr. 0.5 Ba 0.5 Mn 0.85 Ni 0.15 O 3-δ Under the induction of a reducing atmosphere, metallic Ni nanoparticles are precipitated in situ and spatially confined and anchored on the perovskite surface, forming an exogenous Ni-perovskite active interface. The application method includes: In a high-temperature oxygen-free or micro-oxygen environment, a mixed gas containing methane and carbon dioxide is introduced into the multiple internal channels, and air or oxygen-containing gas is introduced into the cathode reaction layer side. The battery is connected to an adjustable load or electrochemical workstation via an external circuit current collector. A bias voltage is applied to the battery, allowing it to undergo methane dry reforming at a voltage lower than the open circuit voltage. The exogenous Ni-perovskite active interface undergoes dynamic oxygen renewal through the regulation of an external electric field. This process is used to eliminate carbon species precursors generated by methane dissociation in situ, achieving anti-carbon deposition operation and outputting electrical energy. The bias voltage is a negative offset relative to the open circuit voltage.

2. The application method according to claim 1, characterized in that, The bias voltage ΔV is less than the open-circuit voltage by no more than 1V, i.e., -1.0 V ≤ ΔV < 0 V.

3. The application method according to claim 1, characterized in that, The operating temperature for the methane reforming reaction is 600–800°C.

4. The application method according to claim 1, characterized in that, The mixed gas containing methane and carbon dioxide includes methane, carbon dioxide, and a carrier gas, with a volume ratio of 2:2:

1.

5. The application method according to claim 4, characterized in that, The total flow rate of the mixed gas is 30-100 ml / min.

6. The application method according to claim 1, characterized in that, The perovskite precursor material Pr 0.5 Ba 0.5 Mn 0.85 Ni 0.15 O 3-δ The amount of precursor adhering to the surface of the channel within the porous anode support is 5 wt%.

7. The application method according to claim 1, characterized in that, The preparation and modification of the catalyst include: High-purity praseodymium nitrate, barium nitrate, manganese nitrate, and nickel nitrate, along with citric acid monohydrate as a complexing agent, were weighed according to stoichiometric ratios and completely dissolved in deionized water. Then, ethylenediaminetetraacetic acid was added to prepare Pr... 0.5 Ba 0.5 Mn 0.85 Ni 0.15 O 3-δ Precursor solution; Using vacuum-assisted impregnation, Pr 0.5 Ba 0.5 Mn 0.85 Ni 0.15 O 3-δ The precursor solution is introduced into the pores of the multi-channel porous anode support; after repeated impregnation and drying, it is heat-treated at 950-1100℃ to make Pr 0.5 Ba 0.5 Mn 0.85 Ni 0.15 O 3-δ The precursor is attached to the inner surface of the porous anode support; A reducing gas is introduced into the internal channel for in-situ reduction at high temperature, promoting the reduction of Pr. 0.5 Ba 0.5 Mn 0.85 Ni 0.15 O 3-δ Ni ions in the perovskite lattice migrate to the surface and precipitate in situ into uniform, spatially confined metallic Ni nanoparticles, thus constructing an exogenous Ni-perovskite active interface in situ.

8. The application method according to claim 7, characterized in that, Pr 0.5 Ba 0.5 Mn 0.85 Ni 0.15 O 3-δ The molar ratio of metal ions, citric acid, and ethylenediaminetetraacetic acid in the precursor solution is 1:2:

1.

9. The application method according to claim 1, characterized in that, The porous anode support is made of NiO-YSZ porous ceramic material, the dense oxygen ion conductor electrolyte layer is made of YSZ, the barrier layer is made of GDC, and the cathode reaction layer is made of porous perovskite material LSCF.

10. The application method according to claim 1, characterized in that, The porous anode support is prepared by phase inversion assisted extrusion. The raw materials used in the preparation solution include NiO powder, YSZ powder, polyethylene glycol-30-dipolyhydroxystearate, N-methylpyrrolidone and binder, and the mass ratio is (90~110):(60~70):(0~2.5):(45~55):(10~20).

Images