72 results about "Pyrochlore" patented technology

The invention discloses a high-oxygen-storage zirconium solid solution material and a preparation method, and belongs to the technical field of rare earth catalytic materials, and the method comprises the following steps: precursor preparation, ultrasonic dispersion, double-gradient precipitation, ultrasonic aging, solid-liquid separation, three-section roasting and furnace cooling. Through the synergistic effect of double-gradient precipitation and ultrasonic aging, coarse grains and non-uniform particle size distribution are avoided, and the material is not prone to abnormal growth of the grains and structural collapse in long-term high-temperature service. Meanwhile, according to the gradient roasting process, through step-by-step regulation and control of crystal densification and crystal lattice reconstruction, separation of a fluorite phase and a pyrochlore phase easily occurring in traditional low-temperature single-section roasting is reduced, a stable crystal phase structure is maintained, it is ensured that the material can still keep sufficient active surface and pore channel structures under the working conditions of high temperature and thermal shock alternation, and the performance of the material is improved. The oxygen storage capacity and the long-term durability of the catalyst carrier are obviously improved.

The invention discloses a pyrochlore structure high-entropy ceramic solidified body material as well as a preparation method and application thereof, and belongs to the technical field of nuclear waste solidification. The preparation method of the high-entropy ceramic solidified body material with the pyrochlore structure comprises the following steps: weighing raw material powder of La2O3, Nd2O3, Sm2O3, Gd2O3, Eu2O3 and ZrO2 according to the proportion in (La0. 2Nd0. 2Sm0. 2Gd0. 2Eu0. 2) 2Zr2O7; the weighed raw material powder is subjected to ball milling treatment, and ball-milled powder is obtained; under the inert gas atmosphere, the ball-milled powder is subjected to heat treatment, and heat-treated powder is obtained; and carrying out spark plasma sintering on the heat treatment powder to obtain the pyrochlore structure high-entropy ceramic solidified body material. The powder is treated by using a heat treatment technology, so that the powder is homogenized, a pyrochlore phase is formed, grain growth is more favorably inhibited, a fine grain structure is obtained, and the irradiation stability and the mechanical property of the pyrochlore material are improved.

The invention discloses a neodymium, gadolinium and erbium doped composite ceramic solidified body and a preparation method thereof, and belongs to the field of non-metallic materials. The ceramic solidified body is of a two-phase structure, and the two phases are pyrochlore and monazite; the composite ceramic solidified body comprises GdPO4, Er2Ti2O7 and NdErTi2O7, and the leaching rate of the composite ceramic solidified body is 10 <-7 > g.m <-2 >. D <-1 >. The preparation method of the solidified body comprises the following steps: by taking Zn2TiO4, CaHPO4, SiO2 and B2O3 as solidified body matrixes, adding lanthanide oxides Nd2O3, Gd2O3 and Er2O3, mixing, uniformly grinding, carrying out high-temperature solid-phase reaction on the obtained mixed powder, and naturally cooling to room temperature after the reaction is finished, so as to obtain the monazite phase and pyrochlore phase ceramic solidified body. The ternary multiphase ceramic solidified body has good mechanical performance and leaching resistance, the leaching rate of lanthanide series elements is in the order of magnitude of 10 <-7 > g.m <-2 >. D <-1 >, and the ternary multiphase ceramic solidified body has an excellent solidification effect and has reference significance for deep geological storage of high-level waste.

A multilayer ceramic electronic device includes an element body 10 including a multilayer portion in which a plurality of dielectric layers 11 and a plurality of internal electrode layers 12 are stacked, wherein at least one of the plurality of dielectric layers 11 includes a pyrochlore phase 50.

The present disclosure provides a ceramic material for a thermal barrier coating and a manufacturing method thereof. A chemical composition of the ceramic material is LaYbZrCeO7. The ceramic material is manufactured by doping LaO1.5, YbO1.5 and CeO2 into ZrO2. A mole ratio of LaO1.5, YbO1.5, CeO2 and ZrO2 is 1:1:1:1. The manufactured ceramic material is in a composite phase structure mainly including a pyrochlore phase and a fluorite phase. The ceramic material according to the present disclosure can effectively inhibit corrosion penetration of molten CMAS in a high temperature environment, which reduces or avoids ceramic cracking and peeling. This better maintains microstructural integrity of the ceramic surface, thereby extending service life of ceramics.

[Problem] To provide a bismuth-ruthenium-oxygen type pyrochlore oxide powder in which the particle size distribution is controlled so as to be advantageous for improving dispersibility in a liquid medium and the intermingling of impurity phases is remarkably reduced. [Solution] A pyrochlore oxide powder that is a powder that has a crystal structure of a bismuth-ruthenium-oxygen type pyrochlore oxide and is composed of particles containing bismuth and ruthenium or containing bismuth, ruthenium, and manganese as metal elements, wherein the cumulative 50% particle diameter D50 in a volume-based particle size distribution determined using a laser diffraction scattering method is 3.0 μm or smaller, and a bismuth-containing phase different from the crystal structure of the pyrochlore oxide is not detected in an X-ray diffraction pattern.

The invention discloses a nuclear waste containing material and a preparation method and application thereof, and belongs to the technical field of nuclear waste treatment.The nuclear waste containing material is characterized in that site-specific doping of trivalent or tetravalent nuclides is achieved through trivalent or tetravalent nuclides, namely, A-site doping is conducted on Lu4Hf3O12 through Z < 3 + > or B-site doping is conducted on Lu4Hf3O12 through Z < 4 + >, the solid solubility of the A-site Z < 3 + > is as high as 25 mol%, and the solid solubility of the B-site Z < 4 + > is as high as 40 mol%; compared with a traditional pyrochlore-based material, the nuclide containing capacity is remarkably improved, the relative density of the nuclear waste containing material is larger than or equal to 95%, and the grain size can reach 1-5 microns; the prepared nuclear waste containing material is excellent in leaching resistance, and the leaching rate of the nuclear waste containing material is 2-4 orders of magnitude lower than that of a conventional curing material; the nuclear waste containing material prepared by the invention has better long-term chemical stability, and the mass loss rate of a highly-doped sample after long-term leaching is reduced by 21% compared with that of a low-doped sample.

The invention relates to an application of ruthenium-based pyrochlore in hydrogen production of an alkaline anion exchange membrane electrolytic bath, which comprises the following steps: providing ruthenium-based pyrochlore Pb2M2-xRuxO7, in which M is Fe, Co, Ni, Cu or Zn, 0 lt; xlt; 2; ruthenium-based pyrochlore and the first mixed solution are mixed and then subjected to ball milling, and first slurry is obtained; removing the first mixed solution in the first slurry to obtain ball-milled ruthenium-based pyrochlore; mixing and dissolving the ball-milled ruthenium-based pyrochlore and carbon powder in a second mixed solution, and adding a dispersing agent for barreling to obtain second slurry; and ultrasonically spraying the second slurry on an anion exchange membrane to serve as an oxygen evolution anode. According to the invention, the ruthenium-based pyrochlore Pb2Ru2O7 is subjected to B-site 3d transition metal doping, so that not only is the use amount of noble metal Ru reduced and the cost of the catalyst reduced, but also the reaction energy barrier of electrolyzed water is jointly reduced under the synergistic effect of Ru and 3d transition metal, and the oxygen evolution activity is further improved.

The invention relates to the technical field of thermal barrier coating materials, in particular to an unequal-ratio Ce doped pyrochlore and fluorite double-phase high-entropy rare earth zirconate thermal barrier coating material and a preparation method thereof. The chemical composition formula of the thermal barrier coating material provided by the invention is (La < 0.2 > Ce < 0.1 > Sm < 0.1 > Dy < 0.2 > Yb < 0.2 > Sc < 0.2 >) < 2 > Zr < 2 > O < 7 >, (La < 0.2 > Sm < 0.2 > Yb < 0.2 > Sc < 0.2 > Y < 0.1 > Ce < 0.1 >) < 2 > Zr < 2 > O < 7 >, and (La < 0.2 > Ce < 0.1 > Nd < 0.1 > Yb < 0.2 > Lu < 0.2 > Sc < 0.2 >) < 2 > Zr < 2 > O < 7 >. The thermal expansion performance of the prepared coating material is obviously improved under the conditions that the low thermal conductivity, the high mechanical property and the high sintering resistance are met at the same time, and therefore the high-entropy rare earth zirconate thermal barrier coating material of the Ce-containing double-phase structure is promoted, and it is guaranteed that the material is practically applied to the field of thermal barrier coating materials.

Provided are a composite oxide powder from which dense solid electrolyte objects having a high ion conductivity can be produced and a method for producing the composite oxide powder. The composite oxide powder is composed of particles comprising lithium (Li), lanthanum (La), zirconium (Zr), and oxygen (O) and having a cubic garnet-type crystal structure, and has a volume particle size distribution in which the 50% diameter (D50) is 1,000 nm or smaller, the composite oxide powder having a pyrochlore phase content of 10 mass % or less.

A method for producing a pyrochlore-type oxide containing a plurality of cations including alkali metal cations in the components, the method comprising: a mixing step (S10, S20) in which a plurality of raw materials each containing a plurality of cations are mixed; and a heating step (S11, S21) in which a mixture containing a plurality of raw materials is heated by a liquid phase method at a predetermined temperature, thereby producing a composite oxide having a corundum structure, the composition of which contains at least an alkali metal cation.

The present invention discloses a Mg / Ba dual-doped catalyst for the catalytic combustion of methane, its preparation method, and application. The catalyst uses La2Ce2O7 as a carrier and Mg and Ba oxides as active components. The carrier and active components are combined using a hydrothermal method, and the catalyst is then uniformly loaded using a colloidal crystal template method. This pyrochlore-type compound (A2B2O7) has high thermal stability, meeting the requirements of a methane oxidative coupling (OCM) catalyst. The catalyst is highly selective, exhibits high catalytic activity in the OCM reaction at low temperatures (<650°C), exhibits high methane removal rates, and produces high yields of C2 products (C2H4 and C2H6), promising broad market applications.

The invention provides a complex-phase high-voltage energy storage dielectric film, a capacitor and a preparation method of the complex-phase high-voltage energy storage dielectric film, the chemical formula of the complex-phase high-voltage energy storage dielectric film material is Bi (4-x) AxTi (3-x) BxO12, A is a + 3-valent rare earth element ion, B is a + 4-valent ion, x represents the doping amount of the A ion or the B ion, x is equal to 0.5-1, and the complex-phase high-voltage energy storage dielectric film material has a part of pyrochlore phase. By forming part of the pyrochlore phase with higher dielectric constant, the energy storage density of the film material and the compression strength of the film material are improved; by accurately controlling the sintering temperature and the material composition, the dielectric loss of the thin film material is effectively reduced, and the energy conversion efficiency is improved; the P-E linetype of the thin film material is optimized, the polarization response is more uniform and stable, and the working stability and reliability of the complex-phase high-voltage energy storage dielectric capacitor can be improved; the preparation process is simple, the production cost can be reduced, the production efficiency can be improved, and the process of converting a new material from a laboratory to the market can be accelerated.

The present application relates to the field of new materials, and aims to provide a preparation method of high-entropy pyrochlore type catalytic material with diatom shell morphology.The method comprises the following steps: immersing diatomite in a mixed solvent of triethanolamine and alcohol, adding a plurality of metal precursor solutions and L-lysine and ascorbic acid, uniformly mixing, then adding hydrogen peroxide and NaOH in sequence;after hydrothermal reaction, adding gluconic acid, and performing hydrothermal reaction again;burning the solid product to obtain the catalytic material.The present application adjusts the metal ion complexes in the precursor solution to make the dissociation degrees of the metal ions similar, so that the metal ions with large electronegativity difference have good cooperativity in the subsequent nucleation and crystallization process, thereby improving the uniformity of the final product and reducing the formation temperature of the pyrochlore phase;the formation temperature of the pyrochlore is reduced through secondary hydrothermal reconstruction crystallization;therefore, the present application can save the production cost of the catalytic material compared with the prior art.

A solid electrolyte for a secondary battery comprises a core phase (101) with a particle shape and a shell phase (102) that covers at least part of the core phase. The shell phase consists of one or more phases. A material component of the core phase includes a pyrochlorine solid electrolyte, which is described by the composition formula Aa 2α Away (1+α) / 3 B2O 7-β X β is shown, where Aa is an alkali metal, Ab is a lanthanide, B is a cationic metal, and X is an anion that can be substituted by O. One material component of the shell phase includes a material with a chemical composition that differs from that of the pyrochlore solid electrolyte and with a melting point that is lower than that of the pyrochlore solid electrolyte.

The application discloses a kind of high oxygen storage cerium zirconium solid solution materials and preparation method, belong to rare earth catalytic material technical field, the method includes the following steps: precursor preparation, ultrasonic dispersion, double gradient precipitation, ultrasonic aging, solid-liquid separation, three-stage calcination and cooling with furnace.The application avoids coarse grain and uneven particle size distribution through the synergistic effect of double gradient precipitation and ultrasonic aging, so that the material is not easy to occur grain abnormal growth and structure collapse in long-term high temperature service.At the same time, the gradient calcination process controls the crystal densification and lattice reconstruction by steps, reduces the separation of fluorite phase and pyrochlore phase which is easy to occur in traditional low temperature single-stage calcination, maintains the stable crystal phase structure, ensures that the material can still retain sufficient active surface and pore structure under high temperature, thermal shock alternating working condition, significantly improves the oxygen storage capacity and long-term durability of catalyst carrier.

The present application relates to a kind of passive radiation cooling multi-host element rare earth cerate ceramic material based on, the chemical formula of this multi-host element rare earth cerate ceramic material is A2Ce2O7, wherein A site is at least 2 kinds of elements in La, Pr, Gd, Lu, and the content of each element is between 25~50%;And have defect fluorite or pyrochlore structure, belong to the system of vertical crystal, Fm-3m space group or Fd-3m space group.The present application combines high infrared radiation performance and heat protection performance, obtains the rare earth cerate ceramic with passive radiation cooling heat dissipation performance, and by improving the infrared radiation performance of material surface, the infrared emissivity of 0.78~2.5 μm band is >0.90, the infrared emissivity of 2.5~16 μm band is >0.90, to maximize the heat radiation heat dissipation effect.The obtained multi-host element rare earth cerate ceramic material has potential application in the field of radiation heat management such as large energy equipment, aero-engine, gas turbine, electronic device, power station boiler.

The application belongs to the technical field of high-entropy materials, and discloses a composite ceramic of Cr2O3-coated high-entropy pyrochlore and a preparation method and application thereof. 0.2 Nd 0.2 Sm 0.2 Gd 0.2 Sc 0.2 )2Zr2O7, wherein x is 5-20 wt.%; the composite ceramic is prepared by the following steps: sintering lanthanum oxide, neodymium oxide, samarium oxide, gadolinium oxide and zirconium oxide at 1400-1700 DEG C to obtain high-entropy pyrochlore powder, stirring the high-entropy pyrochlore powder in a CrCl3 solution after ball milling, drying to obtain CrCl3-coated high-entropy pyrochlore powder, cold sintering the CrCl3-coated high-entropy pyrochlore powder at 200-400 DEG C and 200-500 MPa, then heat preservation at 800-900 DEG C, and then pressureless sintering at 1500-1700 DEG C. The composite ceramic has high density, excellent radiation resistance and leaching resistance, and can be applied in the field of nuclear waste solidification.

The application discloses an infrared heat shielding type rare earth hafnate-based composite ceramic coating material and a preparation method thereof, and belongs to the technical field of thermal barrier coating materials.The application aims to solve the problem that the existing rare earth hafnate ceramic material mainly in pyrochlore / defect fluorite structure has the advantages of low thermal conductivity and high temperature phase stability, but does not have shielding effect on infrared heat radiation, the prepared thermal barrier coating is penetrated by infrared heat radiation at high temperature, the metal substrate is directly radiated and heated, and the working life of the coating material is reduced.The spinel structure ceramic with low infrared transmittance, high infrared emissivity and high infrared absorptivity is used as a dispersed phase to modify the rare earth hafnate-based phase ceramic with pyrochlore / defect fluorite structure, and an infrared heat shielding type composite ceramic coating material with low thermal conductivity, high temperature phase stability and ultralow infrared transmittance is prepared, and the material has a good application prospect.

This application provides an integrated temperature-sensitive thermal barrier protection A2B2O7 ceramic material, its preparation method, and its application, which possesses A... 2‑ a The B2O7:aX material has a general structural formula and a crystal structure that is defective fluorite, pyrochlore, or a mixed two-phase structure. Doping with two or more types of luminescent ions allows for temperature measurement based on the fluorescence intensity ratio of non-thermally coupled energy levels, overcoming the limitations of relative sensitivity in traditional thermally coupled energy level temperature measurement. It utilizes the anti-thermal quenching or low-thermal quenching effects of the luminescent ions to extend the upper limit of temperature measurement, and the different temperature response characteristics of different luminescent ions enhance relative sensitivity. This material can be directly used to prepare a dual-function integrated coating for temperature sensing and thermal barrier protection, eliminating the difficulties of externally mounted sensors, avoiding damage to the coating integrity, and simplifying the complex layout of functional layers. It achieves the integration of thermal barrier protection and high-temperature sensing functions, providing a forward-looking solution for the safety assurance and condition monitoring of components operating in extreme high-temperature environments such as aero-engines and gas turbines.

The application discloses a thermal spraying flame heat recovery and recycling device based on emissivity regulation, and aims at solving the problems of serious flame heat dissipation, low energy utilization rate and insufficient melting of high melting point powder in the existing plasma thermal spraying process. The thermal spraying flame heat recovery and recycling device is provided with a heat recovery cover at the outlet end of a plasma thermal spraying device, the heat recovery cover is a high-temperature-resistant shell, the high-temperature-resistant shell is internally provided with a hollow cavity, the hollow cavity forms a vacuum heat insulation interlayer, the inner surface of the cover of the high-temperature-resistant shell is provided with a high-emissivity coating, the high-emissivity coating is a perovskite coating, a spinel coating or a pyrochlore / defect fluorite coating, the outer surface of the cover of the high-temperature-resistant shell is provided with a low-emissivity coating, and the low-emissivity coating is a metal-doped ZnO coating. The thermal spraying flame heat recovery and recycling device can not only significantly improve the energy utilization rate of the thermal spraying flame, but also improve the coating quality and service protection performance.

A method for producing a solid electrolyte having a pyrochlore-type crystal structure containing alkali metals, lanthanides, at least one specific element from transition elements, group 13 elements, group 14 elements, or group 15 elements, and halogen elements, comprising a mixing step (S11, S14, S21) for mixing a plurality of raw materials for the solid electrolyte to produce a raw material mixture, and a firing step (S12, S15, S22) for heating and firing the raw material mixture at a predetermined temperature. The raw materials include alkali metal compounds, lanthanide compounds, and specific element compounds. When the specific surface area of ​​the alkali metal compound is S1, the specific surface area of ​​the specific element compound is S2, and the specific surface area of ​​the lanthanide compound is S3, the relationships S1 / S2≦50 and S3 / S2≧0.01 exist.

An object of the present invention is to provide an oxygen absorbing and releasing material and a manufacturing method thereof which improve oxygen absorbing and releasing capacity at low temperatures and ensure heat resistance. The oxygen absorbing and releasing material of the present invention contains ceria-zirconia-based composite oxide containing ceria (CeO2) and zirconia (ZrO2), the ceria-zirconia-based composite oxide containing praseodymium (Pr) or neodymium (Nd) as an additive element, at least a part of the ceria-zirconia-based composite oxide having at least one ordered phase of a kappa phase and a pyrochlore phase, 40% to 100% of primary particles having a particle diameter of 0.4 μm to 1.5 μm existing on a basis of the number of particles, an X-ray diffraction pattern being obtained by X-ray diffraction using CuKα after heating at a temperature condition of 1100°C for 5 hours in the atmosphere, an I(14 / 29) value calculated from the X-ray diffraction pattern being 0.015 or more, and an I(28 / 29) value being 0.08 or less.

This invention discloses a Ga-Mn dual-doped pyrochlore-type La₂Zr₂O₇ low-temperature ceramic electrolyte and a fuel cell. The low-temperature ceramic electrolyte has a single-phase pyrochlore structure and the chemical formula La. 2‑ x Ga x Zr 2‑x Mn x O 7‑δ Where 0.2≤x≤0.6; Ga is Ga 3+ The form replaces part of the La bit, Mn with Mn 2+ / Mn 3+ / Mn 4+ By substituting some Zr sites, co-doping induces oxygen vacancy enrichment and modulates local charge distribution, thereby promoting oxide ion transport. The optimized composition of this invention, La... 1.6 Ga 0.4 Zr 1.6 Mn 0.4 O 7‑δ The ionic conductivity reaches 0.28 S·cm at 550 °C. ‑1 The activation energy was reduced to 0.678 eV; a single cell constructed using this electrolyte achieved 1171 mW·cm⁻¹ at 550 °C. ‑2 The peak power density is reduced to 0.37 Ω; the present invention realizes rapid oxide ion transport of La2Zr2O7-based electrolyte under medium and low temperature conditions, which can be used in high-performance solid oxide fuel cells.

A component for use in a plasma processing chamber system is provided. A component body has a plasma facing surface. The plasma facing surface comprises a pyrochlore, comprising at least one of zirconium and hafnium and at least one of lanthanum (La), samarium (Sm), yttrium (Y), erbium (Er), cerium (Ce), gadolinium (Gd), ytterbium (Yb), and neodymium (Nd).

This method for producing a pyrochlore-type oxide is provided with: a mixing step (S30) in which a composite oxide containing at least cations other than alkali metal cations is mixed with an alkali metal compound containing alkali metal cations; and a firing step (S40) for generating a pyrochlore-type oxide by heating the mixture containing the composite oxide and the alkali metal compound at a predetermined temperature. When the composite oxide contains alkali metal cations, the composition ratio of the alkali metal cations in the composite oxide is smaller than the composition ratio of the alkali metal cations in the alkali metal compound. The mixture contains an alkali metal compound in excess of the stoichiometric ratio with respect to the pyrochlore-type oxide. In the firing step, the alkali metal compound is liquefied by heating at a predetermined temperature.

An yttrium-containing structure comprises: (a) a substrate layer comprising a metal alloy, a ceramic material, a ceramic composite, or a combination thereof; (b) a bond-coat layer disposed on the substrate layer, or on an optional interlayer that is on the substrate layer, wherein the bond-coat layer comprises yttrium and a noble metal selected from the group consisting of platinum, iridium, rhenium, ruthenium, rhodium, osmium, and / or palladium; (c) a thermally grown oxide layer disposed on the bond-coat layer, wherein the thermally grown oxide layer comprises yttrium oxide; and (d) optionally, a top-coat layer disposed on the thermally grown oxide layer, wherein the top-coat layer comprises a metal oxide, a metal pyrochlore, or a metal silicate. Yttrium may be replaced with lutetium, in which the bond-coat layer comprises lutetium and a noble metal (e.g., Pt or Ir). A mixture of yttrium and lutetium may also be employed.

A composition comprising a rare earth-doped zirconium / hafnium oxide is provided that has a defect-fluorite structure or a pyrochlore structure. The rare earth-doped zirconium / hafnium oxide has a formula: (Ln1aLn2aLn3aLn4aLn5b)2M2O7 where each of Ln1, Ln2, Ln3, Ln4, and Ln5 is a different rare earth element such that Ln1 and M have a first atomic radius ratio that is 1.35 to 1.45, Ln2 and M have a second atomic radius ratio that is 1.35 to 1.45, Ln3 and M have a third atomic radius ratio that is 1.46 to 1.78, and Ln4 and M have a fourth radius ratio that is 1.46 to 1.78; a is 0.2 or 0.25; b is 0.2 when a is 0.2, and b is 0 when a is 0.25; and M is Zr, Hf, or a mixture thereof. Methods of forming a coating that includes this composition, along with the resulting coated components, are also provided.

Provided is a method for manufacturing a pyrochlore-type solid electrolyte containing: a plurality of cations including metal cations; a halogen element; and a defect structure. The method includes: a mixing step (S16) for preparing a mixed starting material obtained by mixing a precursor of the solid electrolyte or a raw material of a precursor and a halogen-containing starting material containing a halogen element; and a firing step (S17) for firing the mixed starting material. In the firing step, the halogen element is volatilized from the solid electrolyte at a halogen volatilization rate Vout, and the halogen element is supplied into a firing atmosphere of the solid electrolyte at a halogen supply rate Vin. In the firing step, if Dp is the median particle diameter of the solid electrolyte, the mixed starting material is fired under an atmosphere having a relationship of Vin / (Vout x Dp) ≥ 0.015.

A method for producing a solid electrolyte that has a pyrochlore-type crystal structure and contains an alkali metal, a lanthanoid, at least one specific element selected from transition elements, group 13 elements, group 14 elements, and group 15 elements, and a halogen element, the method comprising: mixing steps (S11, S14, S21) for mixing a plurality of raw materials of the solid electrolyte to produce a raw material mixture; and firing steps (S12, S15, S22) for heating the raw material mixture at a prescribed temperature to fire the mixture. The raw materials include an alkali metal compound, a lanthanoid compound, and a specific element compound. When S1 is defined as the specific surface area of the alkali metal compound, S2 is defined as the specific surface area of the specific element compound, and S3 is defined as the specific surface area of the lanthanoid compound, the relationships S1 / S2 ≤ 50 and S3 / S2 ≥ 0.01 hold true.