Non-vacuum preparation method of infinite-layer nickel-based superconducting thin film

Abstract

The invention provides a non-vacuum preparation method of an infinite-layer nickel-based superconducting thin film. The main conception of the method is as follows: dissolving a metal cation soluble precursor in a solvent according to a stoichiometric ratio, and spin-coating the metal cation soluble precursor on the surface of a single crystal nickel-based perovskite oxide substrate to form a thin film precursor; annealing in a high oxygen pressure atmosphere to obtain a thermodynamic metastable-phase perovskite structure intermediate; and finally, converting the thin film into the infinite-layer nickel-based superconducting thin film by using a reduction condition. The method has the advantages that the dependence on vacuum equipment is completely avoided, the operation is simple and convenient, the cost is low, and flexible regulation and high-repeatability preparation of film components can be realized. The prepared infinite-layer nickel-based superconducting thin film has an abnormal superconducting characteristic, the superconducting temperature of the thin film can break through the McMilan limit, and the thin film shows a high upper critical field and critical current density. The material has application value in the fields of superconducting quantum interference devices (SQUID), strong field magnet coils, high-frequency low-loss power transmission cables and magnetic confinement nuclear fusion device magnet systems.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of functional materials, and relates to a non-vacuum preparation method of an infinite-layer nickel-based superconducting thin film. BACKGROUND

[0002] With niobium [1] , niobium-titanium alloy [2] Compared with traditional superconducting materials, unconventional superconducting materials represented by d-orbital transition group strong correlation compounds have the advantages of high critical temperature and strong electric application potential in breaking the McMillan limit, and have application value in the fields of strong-field magnets, quantum computing and low-loss energy transmission [3] . Among them, the near superconducting transition temperature of copper-based oxides, iron-based pnictides or chalcogen compounds, and nickel-based oxides can exceed the McMillan limit, and the representative material components include: YBa2Cu3O 7-δ Copper-based oxides [4] ; SmFeAsO 1-x Iron-based compounds [5] , Sm 1-x-y-z Eu x Ca y Sr z NiO2 nickel-based oxides [6] . Among them, the unconventional superconducting characteristics of nickel-based infinite-layer oxide thin film materials were discovered in 2019, which can exhibit superconducting characteristics under normal pressure, and the near superconducting transition temperature range is 9-15 K [7] , and compared with similar transition group oxides, high-temperature superconductors have good functional stability in air, for example, the ΔT c <5% [8] after 72 hours of exposure.

[0003] The chemical composition of the nickel-based infinite-layer oxide is RE 1-x AE x NiO2, RE is a rare earth element, AE is an alkaline earth element. At present, the preparation of nickel-based infinite-layer oxide thin film mainly includes the following steps: first, using pulsed laser deposition [9] , molecular beam epitaxy

[10] ; then, reduction with CaH2 [9] , Al reducing metal

[11] . However, due to the difficulty of nickel element in the material to stably present Ni 4+ valence under normal conditions, the grown 113-type perovskite precursor is extremely sensitive to growth conditions. For example, the fluctuation of oxygen partial pressure ± 0.1 MPa will cause the thin film to appear NiO impurity phase or induce RE 2O3 segregation

[12] In addition to the low repeatability of the current preparation method, the existing pulsed laser deposition, molecular beam epitaxy technology relies on expensive vacuum equipment, making the preparation cost of nickel-based infinite layer oxide film high.

[0004] In summary, the preparation of existing nickel-based superconducting thin films mainly relies on expensive vacuum equipment, and the repeatability of its superconducting properties is low; and at present, there is still a lack of a low-cost, high-reliability, high-quality preparation method for nickel-based infinite layer oxide film.

[0005]

Reference

[10] GU Q, LI Y, WAN S, et al. Single particle tunneling spectrum of superconducting Nd 1-x Sr x NiO2 thin films [J]. Nature Communications, 2020, 11(1): 6027.

[11] WEI W, VU D, ZHANG Z, et al. Superconducting Nd 1-x Eu xNiO2 thinfilms using in situ synthesis[J]. Science Advances, 2023, 9(27): eadh3327.

[12] GOODGE B H, LI D, LEE K, et al. Doping evolution of the Mott–Hubbard landscape in infinite-layer nickelates[J]. Proceedings of the National Academy of Sciences, 2021, 118(2): e2007683118. SUMMARY

[0006] The present application aims to provide a low-cost, high-reliability, high-quality preparation method of nickel-based infinite-layer oxide thin films.

[0007] A non-vacuum preparation method of infinite-layer nickel-based superconducting thin films, the chemical composition of the infinite-layer nickel-based superconducting thin films is RE 1-x ( RE ’ 1-y AE y ) x NiO2, wherein RE ' is a rare earth element and can be converted to +2 valence under the used reduction conditions, RE is a rare earth element and maintains +3 valence under the used reduction conditions, AE is an alkaline earth element, 0 < x < 1, 0 ≤ y ≤ 1; the non-vacuum preparation method comprises the following steps: first, the metal cation soluble precursor involved is dissolved in a solvent according to the target stoichiometric ratio, and the obtained solution is spin-coated on the surface of a single-crystal nickel-based perovskite oxide substrate having a certain in-plane lattice mismatch relationship with the target thin film; second, the 113-type perovskite structure oxide thin film in the thermodynamic metastable phase is obtained by annealing under a high oxygen pressure atmosphere; finally, the prepared 113-type nickel-based perovskite structure oxide is reduced to a 112-type infinite-layer nickel-based superconducting thin film by using a reduction condition, in the process RE ' is all or part of the +2 valence, RE maintains +3 valence.

[0008] The infinite-layer nickel-based superconducting thin films prepared by this invention exhibit anomalous superconductivity, with superconducting temperatures exceeding the McMillan limit. This has application value in superconducting quantum interference devices, strong-field magnet coils, and high-frequency, low-loss cables. Compared to existing vacuum-dependent methods for preparing infinite-layer nickel-based superconducting thin films, the method provided by this invention is simpler and less expensive. It allows for flexible control of the film composition and significantly improves the growth quality and reliability of the prepared superconducting thin films.

[0009] Furthermore, the preparation of the infinite-layer nickel-based superconducting thin film uses salts of the metal cation elements involved in the infinite-layer nickel-based superconducting thin film as precursors. These precursors are dissolved in an organic solvent and spin-coated onto single-crystal substrates of different crystal phases, sizes, and compositions. Under different high-oxygen-pressure environments, annealing for different times forms rare-earth nickelate precursors. Then, a secondary heat treatment is performed in a reducing environment at a certain temperature to reduce the precursor film to an infinite-layer structure. The prepared infinite-layer structure thin film exhibits superconducting properties with higher upper critical field and critical current density compared to conventional and unconventional superconductors, and can be... RE , RE' , AE The superconducting properties are adjusted by the lattice mismatch and coherence of the substrate thin film.

[0010] Furthermore, in the chemical composition of the infinite-layer nickel-based superconducting thin film RE Preferred minerals include europium (Eu), samarium (Sm), and thulium (Tm). RE The preferred elements are lanthanum (La), cerium (Ce), neodymium (Nd), praseodymium (Pr), samarium (Sm), and gadolinium (Gd). AE Calcium (Ca), strontium (Sr), and barium (Ba) are preferred.

[0011] Further, the soluble precursor of the metal cation includes its nitrate, acetate, isooctanoate, carbonate, chlorate and sulfate, preferably neodymium nitrate, samarium nitrate, europium nitrate, praseodymium nitrate, strontium nitrate, barium nitrate, lanthanum nitrate, dysprosium nitrate, gadolinium nitrate, holmium nitrate and thulium nitrate; the solvent includes aqueous solvents, alcohol solvents, ketone solvents, ether solvents, ester solvents, halogenated hydrocarbon solvents, hydrocarbon solvents, nitrogen-containing solvents and sulfur-containing solvents, preferably ethylene glycol methyl ether, xylene, isooctanoic acid and ammonia.

[0012] Furthermore, single-crystal nickel-based perovskite oxide substrates with a certain in-plane lattice mismatch relationship include: neodymium gallium oxide (NdGaO3) and strontium tantalum aluminate (LaAlO3). 0.29 -(SrAl 1 / 2 Ta 1 / 2 O3) 0.71 Strontium titanate (SrTiO3), Lanthanum aluminate (LaAlO3), Lead magnesium niobate-lead titanate (Pb(Mg)) 1 / 3 Nb 2 / 3)O3-PbTiO3, SrRuO3, KTaO3, LiNbO3, LuAlO3, YAlO3, LaSrAlO4, NdAlO3, LaSrGaO4, LaGaO3, DyScO3, TbScO3, GdScO3, EuScO3, SmScO3, NdScO3, BaTiO3, PrScO3, LaLuO3, MgO, preferably NdGaO3, (LaAlO3) 0.29 -(SrAl 1 / 2 Ta 1 / 2 O3) 0.71 , SrTiO3, LaAlO3; the crystal surface orientations thereof include: 110, 100, 001, 111, 010, 101, preferably 110 and 001; the lattice mismatch degree thereof with the lattice of the 113-type nickel-based perovskite oxide intermediate product to be prepared ranges from -2.5% to +10.0%, preferably 0% to 3%; the lattice mismatch degree thereof with the target oxide ranges from -2.5% to +10.0%.

[0013] Further, the oxygen pressure of the high-oxygen-pressure atmosphere ranges from 0.2 to 100 MPa, preferably from 0.5 to 30 MPa; the high-oxygen-pressure annealing temperature ranges from 200 to 1000 °C, preferably from 500 to 900 °C; through the optimized selection of the three of the annealing oxygen pressure, temperature, and substrate and thin film lattice mismatch degree, the original positive Gibbs free energy of the 113-type nickel-based perovskite oxide precursor in the thermodynamic metastable phase is reduced to a negative value and grows epitaxially on the perovskite substrate surface in a non-uniform nucleation manner.

[0014] Further, the hydrogenation process is the co-annealing of the reducing substance and the precursor oxide in a phase diagram vacuum environment; the reducing substance includes: NaH, H2 and mixed gas thereof, CaH2, Al, NaBH4, LiAlH4, SO2, H2S, CO, Na2S, Na2SO3, KI, and H2C2O4, preferably CaH2, H2 and mixed gas thereof; the annealing temperature ranges from 50 to 500 °C; the annealing time ranges from 30 minutes to 24 hours.

[0015] Further, the prepared infinite-layer nickel-based superconducting thin film has superconducting properties at normal pressure, and the critical superconducting temperature, upper critical field and critical current density thereof can be adjusted by adjusting the component ratio, substrate lattice mismatch degree, and reduction process parameters. RE 、 RE' 、 AE ​、 By controlling the critical current density, the prepared materials can be applied to superconducting quantum interference devices, strong field magnet coils, high-frequency low-loss power transmission cables, and magnet systems for magnetic confinement nuclear fusion devices.

[0016] The advantages of this invention lie in its complete avoidance of reliance on vacuum equipment, its simplicity and low cost, and its ability to achieve flexible control of thin film composition and highly reproducible preparation. The prepared infinite-layer nickel-based superconducting thin film exhibits anomalous superconductivity, with its superconducting temperature exceeding the McMillan limit, and displays a high upper critical field and critical current density. This material has application value in the fields of superconducting quantum interference devices (SQUIDs), strong-field magnet coils, high-frequency low-loss power transmission cables, and magnet systems for magnetic confinement fusion devices. Attached Figure Description

[0017] Figure 1 Neodymium-Europium Nickel Oxide (NdO) prepared by the method of this invention 0.55 Eu 0.45 Resistance-temperature relationship curves of NiO3 perovskite precursor films.

[0018] Figure 2 Neodymium-Europium Nickel Oxide (NdO) prepared by the method of this invention 0.55 Eu 0.45 X-ray diffraction pattern of NiO2 infinite-layer superconducting thin film.

[0019] Figure 3 Neodymium-Europium Nickel Oxide (NdO) prepared by the method of this invention 0.55 Eu 0.45 Resistance-temperature relationship curves of NiO2 infinite-layer superconducting thin films.

[0020] Figure 4 Neodymium-Europium Nickel Oxide (NdO) prepared by the method of this invention 0.6 Eu 0.4 Resistance-temperature relationship curves of NiO3 infinite-layer superconducting thin films.

[0021] Figure 5 To prepare infinite-layer superconducting Nd: europium nickel oxide perovskite (Nd: N ... 0.6 Eu 0.4 Resistance-temperature relationship curves of NiO2 thin films.

[0022] Figure 6 Neodymium-Europium Nickel Oxide (NdO) prepared by the method of this invention 0.45 Eu 0.55 Resistance-temperature relationship curves of NiO3 infinite-layer superconducting thin films. Detailed Implementation

[0023] Unless otherwise indicated, the various materials used in the present application can be obtained commercially or prepared by conventional techniques known to those of ordinary skill in the art. Except in the Examples, or where otherwise explicitly indicated, all measurements are understood to be made at standard conditions, that is, a temperature of 23 °C and an atmospheric pressure of 1 atmosphere. All percentages and amounts expressed herein and elsewhere in the specification should be understood and interpreted to be preferred ranges to obtain the best results according to this invention. Unless otherwise stated, the term "about" when used in connection with a numerical value throughout the disclosure means ±10% of the value. Furthermore, any method and material similarly or equivalently effective for the purposes disclosed and claimed herein can also be used in the practice of the present application.

[0024] Other aspects of the application will be apparent to those of ordinary skill in the art from the disclosure herein.

[0025] The application is further described in terms of the following examples. It will be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the application. The experimental methods in the following examples, unless otherwise indicated, were carried out under conventional conditions or as recommended by the manufacturer.

[0026] Test Methods: We used XRD, STEM, PPMS means to characterize the synthesized thin film materials. The characterization methods are carried out according to the general standards in the art.

[0027] Example 1: The neodymium nitrate and europium nitrate and nickel acetate were dissolved in ethylene glycol methyl ether solvent to prepare a rare earth nickel-based oxide precursor solution according to the stoichiometric ratio of neodymium to europium to nickel 0.55:0.45:1. In order to promote the dissolution of the precursor solution, it was stirred on a stirring table for 6 hours until the solution was uniformly diffused. The above-mentioned precursor solution was uniformly spin-coated on a gallate NdGaO3 substrate with an orientation of 110 to prepare a neodymium europium nickel oxide perovskite thin film, and finally baked at 175 degrees Celsius for 2 minutes. Subsequently, the thin film was placed in an annealing furnace for high oxygen pressure annealing, with an annealing pressure of 9 megapascals of oxygen atmosphere, an annealing temperature of 800 degrees Celsius, and a time of 6 hours. The prepared neodymium europium nickel oxide thin film showed that it had a perovskite pure phase structure, and a sudden change in the material resistivity was observed at a temperature of 277K-300K, as shown in FIG. 1. The thin film was wrapped with aluminum foil, and calcium hydride powder was completely covered on the aluminum foil, and then it was placed in a tube furnace for secondary heat treatment, and the precursor thin film obtained by high oxygen pressure annealing was reduced to an infinite layer nickel-based superconducting thin film, with a heat treatment pressure of 1 x 10 Figure 1 -4 Pascals, a temperature of 290 degrees Celsius, and a time of 2 hours. The XRD of the prepared neodymium europium nickel oxide thin film changed significantly, from the original 113-type perovskite structure to the 112-type infinite layer structure, as shown in FIG. 2, and it had superconducting transition characteristics, as shown in FIG. 3. Figure 2 Figure 3

[0028] Example 2: ​​​Neodymium nitrate and europium nitrate and nickel acetate were dissolved in ethylene glycol methyl ether solvent to form a rare earth nickel-based oxide precursor solution with a stoichiometric ratio of neodymium to europium to nickel of 0.6:0.4:1. The solution was stirred on a stirring table for 6 hours until the solution was uniform. A neodymium europium nickel oxide perovskite film was prepared by spin coating the precursor solution onto a gallate NdGaO3 substrate oriented at 110, and then placing the film in an oven at 175 degrees Celsius for 2 minutes. The film was then annealed in an annealing furnace under high oxygen pressure, with an annealing pressure of 9 megapascals of oxygen atmosphere, an annealing temperature of 800 degrees Celsius, and an annealing time of 6 hours. The prepared neodymium europium nickel oxide film had a perovskite pure phase structure, and a material resistivity anomaly was observed at a temperature of 255 K to 280 K. The neodymium europium nickel oxide perovskite film was wrapped in aluminum foil, and calcium hydride powder was completely covered on the aluminum foil wrapped sample. Finally, the sample was placed in a tube furnace for secondary heat treatment, and the neodymium europium nickel oxide perovskite film was reduced to an infinite layer nickel-based superconducting film, with a heat treatment pressure of 1 x 10 -4 pascals, an annealing temperature of 290 degrees Celsius, and an annealing time of 2 hours. The prepared neodymium europium nickel oxide film was converted from a perovskite phase to an infinite layer structure, and had superconducting transition characteristics, as shown in FIG. 2. Figure 4

[0029] Example 3 Neodymium, europium, and nickel were dissolved in ethylene glycol methyl ether solvent to form a 0.2 mol / L rare earth nickel-based oxide precursor solution with a stoichiometric ratio of neodymium to europium to nickel of 0.45:0.55:1. The solution was stirred for 6 hours until the components were uniform. A neodymium europium nickel oxide perovskite film was prepared by spin coating the precursor solution onto a gallate NdGaO3 substrate oriented at 110, and then placing the film in an oven at 175 degrees Celsius for 2 minutes. The film was then annealed under high oxygen pressure, with an annealing atmosphere of oxygen, an annealing pressure of 9 megapascals, an annealing temperature of 800 degrees Celsius, and an annealing time of 6 hours. The prepared neodymium europium nickel oxide film had a 113-type perovskite pure phase structure, and a material resistivity anomaly was observed at a temperature of 328 K to 350 K, as shown in FIG. 3. Figure 5 The neodymium europium nickel oxide perovskite film was wrapped in aluminum foil, and calcium hydride powder was uniformly covered on the aluminum foil, and then the sample was placed in a tube furnace for hydrogenation treatment, so that the neodymium europium nickel oxide perovskite film was reduced to an infinite layer nickel-based superconducting film, with a treatment pressure of 1 x 10 -4 pascals, an annealing temperature of 290 degrees Celsius, and an annealing time of 2 hours. The prepared superconducting neodymium europium nickel oxide film was observed to have a phase structure converted from a perovskite phase to a 112-type infinite layer structure, and had superconducting transition characteristics, as shown in FIG. 4. Figure 6

[0030] Example 4 ​​Neodymium, europium and nickel were dissolved in ethylene glycol methyl ether solvent with stoichiometric ratio of 0.45:0.50:1, respectively, using neodymium nitrate, europium nitrate and nickel acetate as raw materials to prepare a rare earth nickel-based oxide precursor solution. The solution was stirred for 6 hours to ensure uniformity of the components. Subsequently, a neodymium-europium-nickel oxide perovskite film was prepared on a neodymium gallate NdGaO3 substrate with an orientation of 110 by a chemical solution deposition method, and baked at 175 degrees Celsius for 2 minutes. Then the film was subjected to high oxygen pressure annealing treatment, with an oxygen atmosphere, a pressure of 0.5 megapascal, a temperature of 500 degrees Celsius, and a duration of 6 hours. The obtained neodymium-europium-nickel oxide film showed a perovskite pure phase structure, and the material resistivity showed a sudden change. The film was wrapped with aluminum foil, and calcium hydride powder was evenly covered on the aluminum foil. The assembly was placed in a tube furnace for hydrogenation treatment, aiming to reduce the neodymium-europium-nickel oxide perovskite film to an infinite layer nickel-based superconducting film. The hydrogenation process was carried out at a pressure of 1×10 -3 pascal and a temperature of 50 degrees Celsius for 2 hours. The prepared neodymium-europium-nickel oxide film was converted from a perovskite phase to an infinite layer structure, showing superconducting transition characteristics.

[0031] Example 5: Neodymium nitrate, europium nitrate and nickel acetate were dissolved in ethylene glycol methyl ether solvent with stoichiometric ratio of neodymium:europium:nickel = 0.65:0.35:1 to prepare a rare earth nickel-based precursor solution, which was stirred for 6 hours to achieve uniformity of the components. A neodymium gallate NdGaO3 substrate was used, with a substrate orientation of 110, to deposit a film by a two-step spin coating process, followed by baking at 175 degrees Celsius for 2 minutes to form a neodymium-europium-nickel oxide perovskite film. The film was annealed at 500 degrees Celsius for 6 hours in an oxygen atmosphere with a pressure of 0.5 megapascal to obtain a perovskite pure phase structure and show a sudden change in resistivity. The film sample was wrapped with aluminum foil and the surface was covered with calcium hydride powder, and placed in a tube furnace for hydrogenation treatment at 1×10 pascal vacuum and 500 degrees Celsius for 2 hours, which was reduced from a 113-type perovskite phase to a 112-type infinite layer nickel-based superconducting film structure, and the material showed superconducting transition characteristics.

[0032] Example 6: Neodymium nitrate, europium nitrate and nickel acetate were dissolved in ethylene glycol methyl ether according to the stoichiometric ratio of neodymium:europium:nickel = 0.7:0.3:1 to prepare a precursor solution, and stirred for 6 hours to ensure uniformity. The neodymium gallate NdGaO3 substrate was oriented at 110, and the film was formed by spin coating. After spin coating, the substrate was baked at 175 degrees Celsius for 2 minutes. High oxygen pressure annealing was performed, and oxygen was introduced to maintain a pressure of 0.5 MPa. The film was annealed at 900 degrees Celsius for 6 hours. The resulting perovskite pure phase film showed a sudden change in resistivity. The film was wrapped in aluminum foil and uniformly covered with calcium hydride powder. The tube furnace was heated to 1×10 -3 Pascal pressure, 50 degrees Celsius, and hydrogenated for 2 hours. The neodymium europium nickel oxide film underwent a phase structure transformation from perovskite to infinite layer structure, and had superconducting transition characteristics.

[0033] Example 7: Neodymium nitrate, europium nitrate and nickel acetate were dissolved in ethylene glycol methyl ether according to the stoichiometric ratio of neodymium:europium:nickel = 0.75:0.25:1 to prepare a precursor solution, and stirred for 6 hours. The neodymium gallate NdGaO3 substrate was oriented at 110, and the film was formed by spin coating. After spin coating, the substrate was baked at 175 degrees Celsius for 2 minutes. High oxygen pressure annealing was performed, and oxygen was introduced to maintain a pressure of 0.5 MPa. The film was annealed at 900 degrees Celsius for 6 hours. The resulting perovskite pure phase film showed a sudden change in resistivity. The film was wrapped in aluminum foil and uniformly covered with calcium hydride powder. The tube furnace was heated to 1×10 -4 Pascal pressure, 500 degrees Celsius, and hydrogenated for 2 hours. The neodymium europium nickel oxide film underwent a phase structure transformation from perovskite to infinite layer structure, and had superconducting transition characteristics.

[0034] Example 8: Neodymium nitrate, europium nitrate and nickel acetate were dissolved in ethylene glycol methyl ether according to the stoichiometric ratio of neodymium:europium:nickel = 0.45:0.55:1 to prepare a precursor solution, and stirred for 6 hours. The neodymium gallate NdGaO3 substrate was oriented at 110, and the film was formed by spin coating. After spin coating, the substrate was baked at 175 degrees Celsius for 2 minutes. High oxygen pressure annealing was performed, and oxygen was introduced to maintain a pressure of 0.5 MPa. The film was annealed at 900 degrees Celsius for 6 hours. The resulting perovskite pure phase film showed a sudden change in resistivity. The film was wrapped in aluminum foil and uniformly covered with calcium hydride powder. The tube furnace was heated to 1×10 -3 Pascal pressure, 50 degrees Celsius, and hydrogenated for 2 hours. The neodymium europium nickel oxide film underwent a phase structure transformation from perovskite to infinite layer structure, and had superconducting transition characteristics.

[0035] Example 9: Neodymium nitrate, strontium nitrate, europium nitrate and nickel acetate were dissolved in ethylene glycol methyl ether solvent according to stoichiometric ratio of neodymium: strontium: europium: nickel = 0.50:0.05:0.45:1 to prepare a rare earth nickel-based precursor solution. The solution was stirred for 6 hours to promote dissolution and ensure uniform diffusion. The thin film was deposited on a 110-oriented neodymium gallate NdGaO3 substrate using a chemical spin coating method, and a neodymium europium nickel perovskite thin film was formed by baking at 175 degrees Celsius for 2 minutes. Subsequently, high oxygen pressure annealing was performed: annealing at 900 degrees Celsius for 6 hours in a 30 mega-pascal oxygen atmosphere. The XRD spectrum of the resulting thin film showed a perovskite pure phase structure, and a resistance jump was observed. The thin film was wrapped in aluminum foil and the surface was covered with calcium hydride powder, and was placed in a tube furnace for secondary heat treatment at 1×10 -3 mega-pascal, 50 degrees Celsius for 2 hours. The thin film was converted from a 113-type perovskite phase to an infinite layer structure, and exhibited superconducting transition characteristics.

[0036] Example 10: Neodymium nitrate, strontium nitrate, europium nitrate and nickel acetate were dissolved in ethylene glycol methyl ether solvent according to stoichiometric ratio of neodymium: strontium: europium: nickel = 0.50:0.05:0.45:1 to prepare a rare earth nickel-based precursor solution. The solution was stirred for 6 hours to promote dissolution and ensure uniform diffusion. The thin film was deposited on a 110-oriented neodymium gallate NdGaO3 substrate using a chemical spin coating method, and a neodymium europium nickel perovskite thin film was formed by baking at 175 degrees Celsius for 2 minutes. Subsequently, high oxygen pressure annealing was performed: annealing at 900 degrees Celsius for 6 hours in a 30 mega-pascal oxygen atmosphere. The XRD spectrum of the resulting thin film showed a perovskite pure phase structure, and a resistance jump was observed. The thin film was wrapped in aluminum foil and the surface was covered with calcium hydride powder, and was placed in a tube furnace for secondary heat treatment at 1×10 mega-pascal, 50 degrees Celsius for 2 hours. The thin film was converted from a 113-type perovskite phase to an infinite layer structure, and exhibited superconducting transition characteristics.

[0037] Example 11: Neodymium nitrate, strontium nitrate, europium nitrate and nickel acetate were dissolved in ethylene glycol methyl ether solvent according to stoichiometric ratio of neodymium: strontium: europium: nickel = 0.50:0.05:0.45:1 to prepare a rare earth nickel-based precursor solution. The solution was stirred for 6 hours to promote dissolution and ensure uniform diffusion. The thin film was deposited on a 110-oriented neodymium gallate NdGaO3 substrate using a chemical spin coating method, and a neodymium europium nickel perovskite thin film was formed by baking at 175 degrees Celsius for 2 minutes. Subsequently, high oxygen pressure annealing was performed: annealing at 900 degrees Celsius for 6 hours in a 30 mega-pascal oxygen atmosphere. The XRD spectrum of the resulting thin film showed a perovskite pure phase structure, and a resistance jump was observed. The thin film was wrapped in aluminum foil and the surface was covered with calcium hydride powder, and was placed in a tube furnace for secondary heat treatment at 1×10 -3Pascal vacuum, 50°C conditions for 2 hours, successfully converted into an infinite layer superconducting thin film. The XRD spectrum of the final product shows characteristic peak shifts, proving that the neodymium calcium europium nickel oxide thin film is converted from a perovskite phase to an infinite layer structure, while the infinite layer superconducting thin film exhibits superconducting transition behavior.

[0038] Example 12: Neodymium nitrate and samarium nitrate and europium nitrate and nickel acetate are dissolved in ethylene glycol methyl ether solvent to prepare a rare earth nickel-based oxide precursor solution in a stoichiometric ratio of neodymium to samarium to europium to nickel 0.44:0.11:0.45:1. In order to promote the dissolution of the precursor solution, it is stirred on a stirring table for 6 hours until the solution is evenly diffused. The above-mentioned precursor solution is uniformly spin-coated on a lanthanum strontium tantalum aluminate (LaAlO3) substrate oriented at 110 using a chemical solvent spin coating method 0.29 -(SrAl 1 / 2 Ta 1 / 2 O3) 0.71 Neodymium samarium europium nickel oxide perovskite thin film is uniformly spin-coated on the substrate, and finally baked at 175 degrees Celsius for 2 minutes. Subsequently, the thin film is placed in an annealing furnace for high oxygen pressure annealing, with an annealing pressure of 0.5 megapascal oxygen atmosphere, an annealing temperature of 500 degrees Celsius, and a time of 6 hours. The XRD of the prepared neodymium samarium europium nickel oxide perovskite thin film shows that it has a pure perovskite phase structure, and the material resistivity has a sudden change characteristic. The thin film is wrapped with aluminum foil, and the calcium hydride powder completely covers the aluminum foil, and then it is placed in a tube furnace for secondary heat treatment. The precursor thin film obtained by high oxygen pressure annealing is reduced to an infinite layer nickel-based superconducting thin film, with a heat treatment pressure of 1×10 -4 Pascal, a temperature of 500 degrees Celsius, and a time of 2 hours. The prepared superconducting neodymium samarium europium nickel oxide thin film is converted from a perovskite phase to an infinite layer structure, and it has a superconducting transition characteristic.

[0039] Example 13: Neodymium nitrate and samarium nitrate and europium nitrate and nickel acetate are dissolved in ethylene glycol methyl ether solvent to prepare a rare earth nickel-based oxide precursor solution in a stoichiometric ratio of neodymium to samarium to europium to nickel 0.33:0.22:0.45:1. In order to promote the dissolution of the precursor solution, it is stirred on a stirring table for 6 hours until the solution is evenly diffused. The above-mentioned precursor solution is uniformly spin-coated on a lanthanum strontium tantalum aluminate (LaAlO3) substrate oriented at 110 using a chemical solvent spin coating method 0.29 -(SrAl 1 / 2 Ta 1 / 2 O3) 0.71The neodymium, samarium, europium, and nickel oxide perovskite thin film is uniformly spin-coated on the substrate, and finally maintained at 175 degrees Celsius for 2 minutes. Subsequently, the thin film is placed in an annealing furnace for high-oxygen-pressure annealing, with an annealing pressure of 0.5 megapascal oxygen atmosphere, an annealing temperature of 900 degrees Celsius, and an annealing time of 6 hours. The XRD of the prepared neodymium, samarium, europium, and nickel oxide perovskite thin film shows that it has a pure perovskite phase structure, and the material resistivity has a sudden change characteristic. The thin film is wrapped with aluminum foil, and calcium hydride powder is completely covered on the aluminum foil, and then it is placed in a tube furnace for secondary heat treatment, and the precursor thin film obtained by high-oxygen-pressure annealing is reduced to an infinite-layer nickel-based superconducting thin film, with a heat treatment pressure of 1 x 10 -4 pascal, a temperature of 500 degrees Celsius, and a time of 2 hours. The prepared superconducting neodymium, samarium, europium, and nickel oxide thin film is converted from a perovskite phase to an infinite-layer structure, and it has a superconducting transition characteristic.

[0040] Example 14: The neodymium, samarium, europium, and nickel oxide perovskite thin film is uniformly spin-coated on the substrate, and finally maintained at 175 degrees Celsius for 2 minutes. Subsequently, the thin film is placed in an annealing furnace for high-oxygen-pressure annealing, with an annealing pressure of 0.5 megapascal oxygen atmosphere, an annealing temperature of 900 degrees Celsius, and an annealing time of 6 hours. The XRD of the prepared neodymium, samarium, europium, and nickel oxide perovskite thin film shows that it has a pure perovskite phase structure, and the material resistivity has a sudden change characteristic. The thin film is wrapped with aluminum foil, and calcium hydride powder is completely covered on the aluminum foil, and then it is placed in a tube furnace for secondary heat treatment, and the precursor thin film obtained by high-oxygen-pressure annealing is reduced to an infinite-layer nickel-based superconducting thin film, with a heat treatment pressure of 1 x 10 0.29 pascal, a temperature of 500 degrees Celsius, and a time of 2 hours. The prepared superconducting neodymium, samarium, europium, and nickel oxide thin film is converted from a perovskite phase to an infinite-layer structure, and it has a superconducting transition characteristic. 1 / 2 pascal, a temperature of 500 degrees Celsius, and a time of 2 hours. The prepared superconducting neodymium, samarium, europium, and nickel oxide thin film is converted from a perovskite phase to an infinite-layer structure, and it has a superconducting transition characteristic. 1 / 2 pascal, a temperature of 500 degrees Celsius, and a time of 2 hours. The prepared superconducting neodymium, samarium, europium, and nickel oxide thin film is converted from a perovskite phase to an infinite-layer structure, and it has a superconducting transition characteristic. 0.71 pascal, a temperature of 500 degrees Celsius, and a time of 2 hours. The prepared superconducting neodymium, samarium, europium, and nickel oxide thin film is converted from a perovskite phase to an infinite-layer structure, and it has a superconducting transition characteristic. -4 pascal, a temperature of 500 degrees Celsius, and a time of 2 hours. The prepared superconducting neodymium, samarium, europium, and nickel oxide thin film is converted from a perovskite phase to an infinite-layer structure, and it has a superconducting transition characteristic.

[0041] Example 15: A rare-earth nickel-based oxide precursor solution was prepared by dissolving neodymium nitrate, praseodymium nitrate, europium nitrate, and nickel acetate in ethylene glycol monomethyl ether solvent at a stoichiometric ratio of neodymium to samarium to europium to nickel of 0.33:0.22:0.45:1. To promote dissolution, the solution was stirred on a stirring table for 6 hours until homogeneous diffusion. The precursor solution was then spin-coated onto lanthanum tantalum aluminate (LaAlO3) with an orientation of 110 using a chemical solvent. 0.29 -(SrAl 1 / 2 Ta 1 / 2 O3) 0.71 Neodymium-praseodymium-europium nickel-oxygen perovskite thin films were uniformly spin-coated onto a substrate and then baked at 175°C for 2 minutes. The films were then subjected to high-pressure annealing in an annealing furnace at 900°C for 6 hours under a 30 MPa oxygen atmosphere. XRD analysis of the prepared neodymium-praseodymium-europium nickel-oxygen perovskite films revealed a pure-phase perovskite structure and abrupt changes in resistivity. The films were then wrapped in aluminum foil, with calcium hydride powder completely covering the foil. A secondary heat treatment in a tube furnace reduced the precursor film obtained from the high-pressure annealing to an infinite-layer nickel-based superconducting film at a pressure of 1 × 10⁻⁶. -4 Pascal temperature, 500 degrees Celsius, 2 hours. The prepared superconducting Nd:praseodymium-europium nickel oxide thin film transforms from a perovskite phase to an infinite layer structure and exhibits superconducting transition properties.

[0042] Example 16: A rare-earth nickel-based oxide precursor solution was prepared by dissolving samarium nitrate, europium nitrate, calcium nitrate, strontium nitrate, and nickel acetate in ethylene glycol monomethyl ether solvent at a stoichiometric ratio of 0.79:0.12:0.04:0.05:1. To promote dissolution, the solution was stirred for 6 hours until homogeneous diffusion. The precursor solution was then uniformly spin-coated onto a 110-oriented strontium titanate (SrTiO3) substrate using a chemical solvent spin-coating method to form a samarium-europium-calcium-strontium-nickel oxide perovskite film. The film was then baked at 175°C for 2 minutes. Subsequently, the film underwent high-pressure annealing in an annealing furnace at a pressure of 0.5 MPa in an oxygen atmosphere for 6 hours at 500°C. XRD analysis of the prepared samarium-europium-calcium-strontium-nickel-oxygen perovskite thin film revealed its pure-phase perovskite structure and abrupt resistivity change. The film was then wrapped in aluminum foil, with calcium hydride powder completely covering the foil. A secondary heat treatment in a tube furnace reduced the precursor film obtained by high-oxygen-pressure annealing to an infinite-layer nickel-based superconducting thin film. The heat treatment pressure was 1 × 10⁻⁶. -4 Pascal, 50°C, 2 hours. The prepared superconducting samarium europium calcium strontium nickel oxide thin film transforms from a perovskite phase to an infinite layer structure and exhibits superconducting transition properties.

[0043] Example 17: Samarium nitrate and europium nitrate and calcium nitrate and nickel acetate were dissolved in ethylene glycol methyl ether solvent to make a rare earth nickel-based oxide precursor solution in stoichiometric ratio of samarium to europium to calcium to nickel 0.75:0.20:0.05:1. To facilitate the dissolution of the precursor solution, it was stirred on a stirring table for 6 hours until the solution was uniformly diffused. The above-mentioned precursor solution was uniformly spin-coated on a strontium titanate SrTiO3 substrate oriented at 110 to make a samarium europium calcium nickel oxide perovskite thin film using a chemical solvent spin coating method, and finally baked at 175 degrees Celsius for 2 minutes. Subsequently, the thin film was placed in an annealing furnace for high oxygen pressure annealing, with an annealing pressure of 0.5 megapascal oxygen atmosphere, an annealing temperature of 900 degrees Celsius, and an annealing time of 6 hours. The XRD of the prepared samarium europium calcium nickel oxide perovskite thin film showed that it had a pure perovskite structure, and the material resistivity had a sudden change characteristic. The thin film was wrapped with aluminum foil, and calcium hydride powder completely covered the aluminum foil, and then it was placed in a tube furnace for secondary heat treatment to reduce the precursor thin film obtained by high oxygen pressure annealing into an infinite layer nickel-based superconducting thin film, with a heat treatment pressure of 1 x 10 -4 pascal, a temperature of 50 degrees Celsius, and a time of 2 hours. The prepared superconducting samarium europium calcium nickel oxide thin film was converted from a perovskite phase to an infinite layer structure, and it had a superconducting transition characteristic.

[0044] Example 18: Neodymium nitrate and barium nitrate and europium nitrate and nickel acetate were dissolved in ethylene glycol methyl ether solvent to make a rare earth nickel-based oxide precursor solution in stoichiometric ratio of neodymium to barium to europium to nickel 0.50:0.05:0.45:1. To facilitate the dissolution of the precursor solution, it was stirred on a stirring table for 6 hours until the solution was uniformly diffused. The above-mentioned precursor solution was uniformly spin-coated on a strontium titanate SrTiO3 substrate oriented at 110 to make a neodymium barium europium nickel oxide perovskite thin film using a chemical solvent spin coating method, and finally baked at 175 degrees Celsius for 2 minutes. Subsequently, the thin film was placed in an annealing furnace for high oxygen pressure annealing, with an annealing pressure of 0.5 megapascal oxygen atmosphere, an annealing temperature of 900 degrees Celsius, and an annealing time of 6 hours. The XRD of the prepared neodymium barium europium nickel oxide perovskite thin film showed that it had a pure perovskite structure, and the material resistivity had a sudden change characteristic. The thin film was wrapped with aluminum foil, and calcium hydride powder completely covered the aluminum foil, and then it was placed in a tube furnace for secondary heat treatment to reduce the precursor thin film obtained by high oxygen pressure annealing into an infinite layer nickel-based superconducting thin film, with a heat treatment pressure of 1 x 10 -4 pascal, a temperature of 500 degrees Celsius, and a time of 2 hours. The prepared superconducting neodymium barium europium nickel oxide thin film was converted from a perovskite phase to an infinite layer structure, and it had a superconducting transition characteristic.

[0045] Example 19: Dissolve terbium nitrate, europium nitrate and nickel acetate in ethylene glycol methyl ether solvent in stoichiometric ratio of 0.55:0.45:1 of terbium, europium and nickel to make a rare earth nickel-based oxide precursor solution. To facilitate the dissolution of the precursor solution, stir on a stirring table for 6 hours until the solution is uniformly diffused. Spin coat the above-mentioned precursor solution on a lanthanum aluminate LaAlO3 substrate with an orientation of 100 using a chemical solvent spin coating method to make a terbium-europium-nickel oxide perovskite thin film. Finally, maintain at 175 degrees Celsius and bake for 2 minutes. Then, place the thin film in an annealing furnace for high-oxygen-pressure annealing. The annealing pressure is 0.5 megapascal oxygen atmosphere, the annealing temperature is 900 degrees Celsius, and the time is 6 hours. The XRD of the prepared terbium-europium-nickel oxide perovskite thin film shows that it has a pure perovskite phase structure, and the material resistivity has a sudden change characteristic. Wrap the thin film with aluminum foil, completely cover the aluminum foil with calcium hydride powder, and then place it in a tube furnace for secondary heat treatment. Reduce the precursor thin film obtained by high-oxygen-pressure annealing to an infinite-layer nickel-based superconducting thin film. The heat treatment pressure is 1 x 10 -4 Pascal, the temperature is 500 degrees Celsius, and the time is 2 hours. The prepared superconducting terbium-europium-nickel oxide thin film is converted from a perovskite phase to an infinite-layer structure, and it has a superconducting transition characteristic.

[0046] Example 20: Dissolve holmium nitrate, europium nitrate and nickel acetate in ethylene glycol methyl ether solvent in stoichiometric ratio of 0.55:0.45:1 of holmium, europium and nickel to make a rare earth nickel-based oxide precursor solution. To facilitate the dissolution of the precursor solution, stir on a stirring table for 6 hours until the solution is uniformly diffused. Spin coat the above-mentioned precursor solution on a lanthanum aluminate LaAlO3 substrate with an orientation of 100 using a chemical solvent spin coating method to make a holmium-europium-nickel oxide perovskite thin film. Finally, maintain at 175 degrees Celsius and bake for 2 minutes. Then, place the thin film in an annealing furnace for high-oxygen-pressure annealing. The annealing pressure is 30 megapascal oxygen atmosphere, the annealing temperature is 500 degrees Celsius, and the time is 6 hours. The XRD of the prepared holmium-europium-nickel oxide perovskite thin film shows that it has a pure perovskite phase structure, and the material resistivity has a sudden change characteristic. Wrap the thin film with aluminum foil, completely cover the aluminum foil with calcium hydride powder, and then place it in a tube furnace for secondary heat treatment. Reduce the precursor thin film obtained by high-oxygen-pressure annealing to an infinite-layer nickel-based superconducting thin film. The heat treatment pressure is 1 x 10 -4 Pascal, the temperature is 50 degrees Celsius, and the time is 2 hours. The prepared superconducting holmium-europium-nickel oxide thin film is converted from a perovskite phase to an infinite-layer structure, and it has a superconducting transition characteristic.

[0047] Example 21: A neodymium nitrate and strontium nitrate and nickel acetate are dissolved in ethylene glycol methyl ether solvent to make a rare earth nickel oxide precursor solution in stoichiometric ratio of neodymium and strontium and nickel 0.55:0.45:1. To facilitate the dissolution of the precursor solution, it is stirred on a stirring table for 6 hours until the solution is uniformly diffused. The precursor solution is uniformly spin-coated on a neodymium gallate NdGaO3 substrate oriented at 110 to make a neodymium strontium nickel oxide perovskite film using a chemical solvent spin coating method, and finally baked at 175 degrees Celsius for 2 minutes. Subsequently, the film is placed in an annealing furnace for high oxygen pressure annealing, with an annealing pressure of 0.5 megapascal oxygen atmosphere, an annealing temperature of 900 degrees Celsius, and a time of 6 hours. The prepared neodymium strontium nickel oxide perovskite film has a perovskite pure phase structure, and the material resistivity has a sudden change characteristic. Subsequently, the film is placed in a tube furnace for secondary heat treatment, with a vacuum pressure of 1 x 10 -4 Pascal, and hydrogen H2 and its mixed gas are introduced to reduce the precursor film obtained by high oxygen pressure annealing into an infinite layer nickel-based superconducting film, with a temperature of 50 degrees Celsius and a time of 2 hours. The prepared superconducting neodymium strontium nickel oxide film is converted from a perovskite phase to an infinite layer structure, and it has a superconducting transition characteristic.

[0048] Example 22: A samarium nitrate and europium nitrate and nickel acetate are dissolved in ethylene glycol methyl ether solvent to make a rare earth nickel oxide precursor solution in stoichiometric ratio of samarium and europium and nickel 0.55:0.45:1. To facilitate the dissolution of the precursor solution, it is stirred on a stirring table for 6 hours until the solution is uniformly diffused. The precursor solution is uniformly spin-coated on a neodymium gallate NdGaO3 substrate oriented at 110 to make a samarium europium nickel oxide perovskite film using a chemical solvent spin coating method, and finally baked at 175 degrees Celsius for 2 minutes. Subsequently, the film is placed in an annealing furnace for high oxygen pressure annealing, with an annealing pressure of 30 megapascal oxygen atmosphere, an annealing temperature of 500 degrees Celsius, and a time of 6 hours. The prepared samarium europium nickel oxide perovskite film has a perovskite pure phase structure, and the material resistivity has a sudden change characteristic. Subsequently, the film is placed in a tube furnace for secondary heat treatment, with a vacuum pressure of 1 x 10 -4 Pascal, and hydrogen H2 and its mixed gas are introduced to reduce the precursor film obtained by high oxygen pressure annealing into an infinite layer nickel-based superconducting film, with a temperature of 500 degrees Celsius and a time of 2 hours. The prepared superconducting samarium europium nickel oxide film is converted from a perovskite phase to an infinite layer structure, and it has a superconducting transition characteristic.

Claims

1. A non-vacuum method of preparation of an infinite layer nickel-based superconducting thin film, characterized in that, The chemical composition of the nickel-based superconducting thin film is RE 1-x ( RE ’ 1-y AE y ) x NiO2, wherein: RE' is a rare earth element that can be converted to +2 valence under reducing conditions; RE is a rare earth element that maintains +3 valence under reducing conditions; AE is an alkaline earth element; wherein 0 < x < 1, 0 ≤ y ≤ 1; the method comprising the steps of: First, the metal cation involved in the soluble precursor is dissolved in the solvent according to the target stoichiometric ratio, and the obtained solution is spin-coated on the surface of a single-crystal nickel-based perovskite oxide substrate with a certain in-plane lattice mismatch relationship with the target thin film; second, the 113-type perovskite structure nickel-based oxide thin film in the thermodynamic metastable phase is obtained by annealing under high oxygen pressure atmosphere; finally, the prepared 113-type perovskite structure oxide is reduced to 112-type infinite layer nickel-based superconducting thin film under reducing conditions, and in the process RE all or part of the transition to +2, RE maintain +3; the prepared infinite layer nickel-based superconducting thin film has the characteristics of abnormal superconductivity, and the superconducting temperature can break through the McMillan limit, and has application value in superconducting quantum interference devices, high-field magnet coils and high-frequency low-loss cables.

2. A non-vacuum method of producing an infinite layer nickel-based superconducting thin film according to claim 1, wherein The preparation method uses the salt of the metal cation element involved in the infinite layer nickel-based superconducting thin film as a precursor, dissolves it in an organic solvent, spin-coats it on a single-crystal nickel-based oxide substrate with different crystal phases and different sizes and components, performs annealing under different high-oxygen-pressure environments for different times to form a rare earth nickelate precursor, and then performs secondary heat treatment under a reducing environment and at a certain temperature to reduce the precursor thin film into an infinite layer structure. The prepared infinite layer structure thin film has superconducting properties of high upper critical field and critical current density compared to conventional and unconventional superconductors, and can be adjusted by RE 、 RE' 、 AE , the lattice mismatch degree and coherent characteristics of the substrate thin film.

3. A non-vacuum method of producing an infinite layer nickel-based superconducting thin film as described in claim 1, wherein, The RE ' is a rare earth element selected from europium Eu, samarium Sm, thulium Tm; RE selected from lanthanum La, cerium Ce, neodymium Nd, praseodymium Pr, samarium Sm, gadolinium Gd; AE selected from calcium Ca, strontium Sr, barium Ba.

4. A non-vacuum method of producing an infinite layer nickel-based superconducting thin film as described in claim 1, wherein, The metal cation soluble precursor includes nitrate, acetate, iso-octanoate, carbonate, chlorate, and sulfate; the solvent includes water-based solvent, alcohol-based solvent, ketone-based solvent, ether-based solvent, ester-based solvent, halogenated hydrocarbon solvent, hydrocarbon-based solvent, nitrogen-containing solvent, and sulfur-containing solvent.

5. A non-vacuum method of producing an infinite layer nickel-based superconducting thin film as described in claim 1, wherein, The metal cation is selected from neodymium nitrate, samarium nitrate, europium nitrate, praseodymium nitrate, strontium nitrate, barium nitrate, lanthanum nitrate, gadolinium nitrate, holmium nitrate, and thulium nitrate; the solvent is selected from ethylene glycol methyl ether, dimethylbenzene, iso-octanoic acid, and ammonia water.

6. A non-vacuum method of producing an infinite layer nickel-based superconducting thin film as claimed in claim 5, wherein, Single-crystal nickel-based perovskite oxide substrates with a certain in-plane lattice mismatch relationship include: neodymium gallium oxide (NdGaO3) and strontium tantalum aluminate (LaAlO3). 0.29 -(SrAl 1 / 2 Ta 1 / 2 O3) 0.71 Strontium titanate (SrTiO3), Lanthanum aluminate (LaAlO3), Lead magnesium niobate-lead titanate (Pb(Mg)) 1 / 3Nb 2 / 3 O3-PbTiO3, SrRuO3 ruthenium ruthenium oxide (SrRuO3), potassium tantalate (KTaO3), lithium niobate (LiNbO3), lutetium aluminate (LuAlO3), yttrium aluminate (YAlO3), lanthanum strontium aluminate (LaSrAlO4), neodymium aluminate (NdAlO3), lanthanum strontium gallium oxide (LaSrGaO4), lanthanum gallium oxide (LaGaO3), dysprosium scandate (DyScO3), terbium scandate (TbScO3), gadolinium scandate (GdScO3), europium scandate (EuS) The crystals are: samarium scandate (SmScO3), neodymium scandate (NdScO3), barium titanate (BaTiO3), praseodymium scandate (PrScO3), lanthanum lutetate (LaLuO3), and magnesium oxide (MgO). Their crystal surface orientations include: 110, 100, 001, 111, 010, 101, preferably 110 and 001. The lattice mismatch between these crystals and the intermediate product (type 113 nickel-based perovskite oxide) to be prepared ranges from -2.5% to +10.0%. The lattice mismatch between these crystals and the target oxide lattice ranges from -2.5% to +10.0%.

7. A non-vacuum method of producing an infinite layer nickel-based superconducting thin film as claimed in claim 6, wherein, The single-crystal nickel-based perovskite oxide substrate is selected from the group consisting of neodymium gallate NdGaO3, lanthanum strontium tantalum aluminate (LaAlO3) 0.29 -(SrAl 1 / 2 Ta 1 / 2 O3) 0.71 , strontium titanate SrTiO3, lanthanum aluminate LaAlO3; and the lattice mismatch degree ranges from 0% to 3%.

8. A non-vacuum method of producing an infinite layer nickel-based superconducting thin film as described in claim 1, wherein, The oxygen pressure of the high-oxygen-pressure atmosphere ranges from 0.2 to 100 MPa, preferably from 0.5 to 30 MPa; the high-oxygen-pressure annealing temperature ranges from 200 to 1000 degrees Celsius, preferably from 500 to 900 degrees Celsius; through optimization of the annealing oxygen pressure, temperature, and lattice mismatch degree of the substrate and the thin film, the original positive Gibbs free energy of the 113-type nickel-based perovskite oxide precursor in a thermodynamic metastable phase is reduced to a negative value and grows in a non-uniform nucleation manner on the surface of the nickel-based perovskite substrate.

9. A non-vacuum method of producing an infinite layer nickel-based superconducting thin film as described in claim 1, wherein, The hydrogenation process is a co-annealing of a reducing substance and the precursor oxide in a phase diagram vacuum environment; the reducing substance includes sodium hydride NaH, hydrogen H2 and mixed gas thereof, calcium hydride CaH2, aluminum Al, sodium borohydride NaBH4, lithium aluminum hydride LiAlH4, sulfur dioxide SO2, hydrogen sulfide H2S, carbon monoxide CO, sodium sulfide Na2S, sodium sulfite Na2SO3, potassium iodide KI, and oxalic acid H2C2O4, preferably calcium hydride, hydrogen H2 and mixed gas thereof; the annealing temperature ranges from 50 to 500 degrees Celsius; the annealing time ranges from 30 minutes to 24 hours.

10. A non-vacuum method of producing an infinite layer nickel-based superconducting thin film as described in claim 1, wherein, The prepared infinite-layer nickel-based superconducting thin film exhibits superconducting properties under ambient pressure, which can be achieved by adjusting... RE , RE' , AE The critical superconducting temperature and upper critical field are achieved by adjusting the component ratio, substrate lattice mismatch, and reduction process parameters. 、 By controlling the critical current density, the prepared materials can be applied to superconducting quantum interference devices, strong field magnet coils, high-frequency low-loss power transmission cables, and magnet systems for magnetic confinement nuclear fusion devices.

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