Manganese-doped iron selenium tellurium superconducting material and preparation method and application thereof

Abstract

The invention discloses a preparation method of a manganese-doped iron selenium tellurium superconducting material, and the preparation method comprises the following steps: mixing iron powder, selenium powder and tellurium powder to obtain first mixed powder; grinding the first mixed powder to obtain ground first mixed powder; performing pressing treatment on the ground first mixed powder to obtain a pressed block; carrying out first sintering on the briquette, then carrying out multi-stage sintering, and then cooling to obtain an iron selenium tellurium superconducting block; grinding the iron-selenium-tellurium superconducting block into iron-selenium-tellurium superconducting powder, and mixing the iron-selenium-tellurium superconducting powder with manganese powder to obtain second mixed powder; and repeating the operation on the second mixed powder to obtain the manganese-doped iron selenium tellurium superconducting material. According to the superconducting material, the manganese element is added in the sintering process, catalytic phase formation is promoted, loss of selenium and tellurium elements is prevented, and the texture orientation and superconducting performance of the superconducting material are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of superconductors, and in particular relates to a manganese-doped iron-selenium-tellurium superconducting material and a preparation method and application thereof. Background Art

[0002] Since the research group of Professor H. Hosono of Japanese scientists discovered superconductivity at 26K in LaFeAsO1-xFx in February 2008, many other iron-based superconducting materials have been discovered one after another. In the same year, Hsu et al. discovered a new type of iron-based superconducting material FeSe with a PbO structure. The superconducting layer of FeSe-based superconducting materials is composed of only -FeSe- layers, which is the simplest iron-based superconducting material known so far. Moreover, compared with FeAs-based superconducting materials, FeSe-based superconducting materials have broader application prospects because they are safe and non-toxic during preparation and research.

[0003] Although the composition and structure of FeSe-based superconducting materials are simple, the preparation of high-performance FeSe-based superconducting materials is still difficult during the powder sintering process. The superconducting properties of FeSe-based superconducting materials are closely related to the ratio of each element in its precursor powder, grinding time, bulk pressing molding process, and material sintering process. Especially in the sintering process, the phase formation of the sintered products obtained by different sintering procedures is relatively complex, and the tetragonal phase with superconducting properties only appears in a very small element ratio range. Therefore, the preparation of FeSe-based superconducting materials with a high superconducting phase ratio is very difficult.

[0004] At present, the preparation of FeSe-based superconducting materials is mainly based on the solid phase sintering method. Since the heat treatment conditions have a great influence on the phase composition, superconducting phase ratio, phase uniformity and superconducting performance of the material, the research on the heat treatment parameters in the sintering process becomes very important. In the general sintering process, in order to obtain high-performance FeSe-based superconducting materials, the temperature is set to rise slowly to near 900℃ or even 1000℃ during sintering, and the insulation time is as long as several days or even two weeks. The annealing time is much longer than the insulation time. However, FeSe-based superconducting materials are very easy to oxidize. The sintering time is long, and the proportion of the superconducting phase produced tends to decrease due to the oxidation of the material. The superconducting transition temperature of the doped iron selenium telluride decreases or even non-superconductivity occurs. Summary of the invention

[0005] In view of the shortcomings of the prior art described above, the object of the present invention is to provide a manganese-doped iron selenium telluride superconducting material and its preparation method and use. The manganese-doped iron selenium telluride superconducting material described in the present application solves the problem that the superconducting performance of the doped iron selenium telluride is reduced due to the long sintering time in the prior art, which leads to the generation of many impurities. The superconducting transition temperature of the manganese-doped iron selenium telluride superconducting material can be as high as 16K, which is higher than that of pure iron selenium telluride material.

[0006] To achieve the above objectives and other related objectives, the present invention is achieved through the following technical solutions.

[0007] The first aspect of the present invention discloses a method for preparing a manganese-doped iron-selenium-tellurium superconducting material. The preparation method comprises the following steps:

[0008] 1) mixing iron powder, selenium powder and tellurium powder to obtain a first mixed powder;

[0009] 2) grinding the mixed powder to obtain a ground first mixed powder;

[0010] 3) pressing the ground first mixed powder to obtain a briquette;

[0011] 4) performing a first sintering on the compact, then performing a multi-stage sintering, and then cooling the compact to obtain an FeSeTe superconducting block;

[0012] 5) grinding the iron-selenium-tellurium superconducting block into iron-selenium-tellurium superconducting powder, and mixing the iron-selenium-tellurium superconducting powder with manganese powder to obtain a second mixed powder;

[0013] 6) Repeating the operations of steps 2) to 4) with the second mixed powder to obtain a manganese-doped iron-selenium-tellurium superconducting material.

[0014] Preferably, steps 1) to 6) are all performed under an inert gas atmosphere. More preferably, the inert gas is selected from one or more of argon, nitrogen, and helium. In a specific embodiment, the inert gas is argon.

[0015] Preferably, in the step 1), the iron powder, selenium powder and tellurium powder are weighed and mixed in a ratio of 1:x:(1-x) among the molar ratio of iron element, selenium element and tellurium element, and the value range of x is 0.3-0.7. For example, the value range of x can be 0.3-0.4, 0.4-0.5, 0.5-0.6. For example, the molar ratio between the iron element, selenium element and tellurium element can be 1:0.3:0.7, 1:0.4:0.6, 1:0.5:0.5. The value range of x makes the prepared superconducting material have good phase formation and high density. If the x is less than 0.3, the density of the obtained superconducting material decreases; if the x is greater than 0.7, the obtained superconducting material has phase separation. In a specific embodiment, the value of x is 0.4.

[0016] More preferably, based on the total mass of the iron powder, the mass fraction of the iron is ≥99.9%.

[0017] More preferably, based on the total mass of the selenium powder, the mass fraction of selenium is ≥99.9%.

[0018] More preferably, based on the total mass of tellurium powder, the mass fraction of tellurium is ≥99.9%.

[0019] Preferably, in the step 2), the grinding is hand grinding.

[0020] More preferably, the hand grinding time is 0.5h to 1h. In a specific embodiment, the grinding is hand grinding for 0.5 hours in a glove box filled with argon protection. The grinding makes the average particle size of the first mixed powder smaller and more uniform, thereby improving the speed and quality of subsequent phase formation.

[0021] Preferably, in step 3), the pressure of the pressing treatment is 6-10 MPa. For example, the pressure of the pressing treatment may be 6 MPa, 7 MPa, 8 MPa, 9 MPa, or 10 MPa.

[0022] Preferably, in step 3), the pressing time is 15-30 min. For example, the pressing time can be 15 min, 18 min, 21 min, 24 min, 27 min, or 30 min.

[0023] Preferably, step 4) is performed under vacuum conditions.

[0024] More preferably, the vacuum degree of the vacuum condition is not higher than 5×10 -4 Pa. As mentioned above, the vacuum degree can be 1×10 - 4 Pa, 2×10 -4 Pa, 3×10 -4 Pa, 4×10 -4 In a specific embodiment, the vacuum degree is 1×10 -4 Pa.

[0025] Preferably, in the step 4), the first sintering step includes heating to the sintering temperature and then keeping warm, the heating time is 3 to 12 hours, the heating rate is 0.5°C / min to 3°C / min, the sintering temperature is 400 to 550°C, and the keeping time is 1 to 5 hours. For example, the heating time can be 3 to 6 hours, 6 to 10 hours, or 10 to 12 hours. For example, the heating rate can be 0.5°C / min to 0.83°C / min, 0.83°C / min to 2°C / min, or 2°C / min to 3°C / min. For example, the sintering temperature can be 400 to 450°C, 450 to 500°C, or 500 to 550°C. For example, the sintering time can be 1 to 2 hours, 2 to 3 hours, 3 to 4 hours, or 4 to 5 hours.

[0026] During the first sintering, the heating speed is relatively slow, which prevents the vapor pressure of selenium from increasing due to excessively fast heating, thereby preventing the sealed container from rupturing, and also prevents the selenium from rapidly vaporizing and escaping from the compact, thereby causing holes or uneven surfaces in the compact. The sintering temperature is lower than the boiling point of selenium and the sublimation temperature of tellurium, thereby ensuring sufficient reaction before the selenium vaporizes and the tellurium sublimates, which is also a further guarantee for preventing the aforementioned adverse conditions.

[0027] In a specific embodiment, the first sintering step includes: heating to a temperature of 500° C. for 10 hours, sintering at 500° C. for 3 hours, and the heating rate is 0.83° C. / min.

[0028] Preferably, in step 4), the multi-stage sintering includes at least two sintering procedures, and the steps of any one sintering procedure include: heating for 0.5h to 2h to a temperature of 800℃ to 820℃, and keeping it warm for 5h to 6h; cooling for 0.5h to 2h to a temperature of 400℃ to 430℃, and keeping it warm for 0.2h to 1h; the cooling rate is 2℃ / min to 3℃ / min; the heating rate is 2℃ / min to 3℃ / min. For example, the number of sintering procedures can be 2, 3, 4, 5, 6, or 7.

[0029] During the multi-stage sintering, the heating speed is relatively slow, which prevents the increase of vapor pressure of selenium due to excessively rapid heating and causes the rupture of the sealed container, and also prevents the rapid vaporization and escape of selenium from the compact, causing holes or uneven surfaces in the compact; the cooling speed is relatively slow, which prevents the dendrite phenomenon caused by excessive supercooling of the crystal due to excessively rapid cooling and also prevents the compact from cracking due to the inability to fully release stress.

[0030] In a specific embodiment, the multi-stage sintering includes four sintering procedures, and the steps of any one of the sintering procedures include: heating to 800° C. for 2 hours and keeping warm for 6 hours; cooling to 450° C. for 2 hours and keeping warm for 1 hour.

[0031] Preferably, in the step 4), after the multi-stage sintering, the product is cooled to room temperature.

[0032] Preferably, in the step 5), the iron-selenium-tellurium superconducting powder and the manganese powder are weighed and mixed in a ratio of 1:(0-0.1) in which the molar ratio of the iron element to the manganese element is not 0. For example, the molar ratio of the iron element to the manganese element can be 1:(0.001-0.02), 1:(0.02-0.04), 1:(0.04-0.06), 1:(0.06-0.08), 1:(0.08-0.1). The manganese has the function of catalyzing phase formation, which can prevent the loss of selenium and tellurium elements, thereby improving the texture orientation of the sample, thereby achieving the effect of improving the superconducting performance of the iron-selenium-tellurium target.

[0033] Preferably, in step 5), based on the total mass of manganese powder, the mass fraction of manganese is ≥ 99.9%

[0034] A second aspect of the present invention discloses a manganese-doped iron-selenium-telluride superconducting material, wherein the manganese-doped iron-selenium-telluride superconducting material is prepared by the method as described above.

[0035] The third aspect of the present invention discloses a use of the manganese-doped iron-selenium-tellurium superconducting material as described above in superconducting films and / or superconducting tapes.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1) In the present application, manganese powder is added to the iron-selenium-tellurium superconducting powder. The manganese powder has the function of catalyzing phase formation and preventing the loss of selenium and tellurium elements, thereby improving the texture orientation of the manganese-doped iron-selenium-tellurium superconducting material and achieving the effect of improving the superconducting performance of the manganese-doped iron-selenium-tellurium superconducting material.

[0038] 2) The present application reduces the total sintering time to about 110 hours, thereby improving the preparation efficiency of the iron-selenium-tellurium superconducting material.

[0039] 3) The present application sets different reaction temperature intervals, lower heating rates and cooling rates to prevent the gasification of the material, thereby obtaining a block with good uniformity and high density, effectively reducing the generation of non-superconducting phases such as Fe7Se8, and improving the superconducting performance of the manganese-doped iron selenium telluride superconducting material. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a photograph of the manganese-doped iron-selenium-tellurium superconducting material described in Example 1;

[0041] Figure 2 is a resistance-temperature curve diagram of the manganese-doped iron-selenium-tellurium superconducting material described in Example 2;

[0042] Figure 3 This is the X-ray diffraction pattern of the manganese-doped iron-selenium-tellurium superconducting material described in Example 2. DETAILED DESCRIPTION

[0043] The following is a description of the implementation of the present invention by means of specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0044] Before further describing the specific embodiments of the present invention, it should be understood that the scope of protection of the present invention is not limited to the specific embodiments described below; it should also be understood that the terms used in the examples of the present invention are intended to describe specific embodiments, rather than to limit the scope of protection of the present invention. The test methods in the following examples without specifying specific conditions are generally carried out under conventional conditions or under conditions recommended by the manufacturers.

[0045] When the embodiments give numerical ranges, it should be understood that, unless otherwise specified in the present invention, both endpoints of each numerical range and any numerical value between the two endpoints can be selected. Unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as those generally understood by those skilled in the art. In addition to the specific methods, equipment, and materials used in the embodiments, according to the grasp of the prior art by those skilled in the art and the record of the present invention, any methods, equipment, and materials of the prior art similar or equivalent to the methods, equipment, and materials described in the embodiments of the present invention can also be used to realize the present invention.

[0046] In the present application, the applicant aims to solve the problem in the prior art that due to the long sintering time, many impurity phases are easily generated, and the superconducting performance of the doped iron, selenium and tellurium is reduced. The applicant provides a manganese-doped iron, selenium and tellurium superconducting material and a preparation method and use thereof. The preparation method greatly reduces the vapor pressure generated by the volatilization of the selenium element through sintering in different temperature ranges, avoids the explosion of the reaction container, obtains a block with good uniformity and high density, and effectively reduces the generation of non-superconducting phases such as Fe7Se8, thereby improving the superconducting performance of the superconducting material; manganese is added to the superconducting material of the present invention, which effectively prevents the loss of selenium and tellurium elements, maintains the ratio of the iron, selenium and tellurium superconducting phases, and improves the texture orientation and superconducting performance of the sample.

[0047] In the following specific embodiment, the method for preparing the manganese-doped iron-selenium-tellurium superconducting material specifically includes the following steps:

[0048] 1) mixing iron powder, selenium powder and tellurium powder to obtain a first mixed powder;

[0049] 2) grinding the mixed powder to obtain a ground first mixed powder;

[0050] 3) pressing the ground first mixed powder to obtain a briquette;

[0051] 4) subjecting the compact to heat treatment, multi-stage sintering, and cooling to obtain an FeSeTe superconducting block;

[0052] 5) grinding the iron-selenium-tellurium superconducting block into iron-selenium-tellurium superconducting powder, and mixing the iron-selenium-tellurium superconducting powder with manganese powder to obtain a second mixed powder;

[0053] 6) Repeating the operations of steps 2) to 4) with the second mixed powder to obtain a manganese-doped iron-selenium-tellurium superconducting material.

[0054] In the following embodiments, based on the total mass of iron powder, the mass fraction of iron is ≥99.9%; based on the total mass of selenium powder, the mass fraction of selenium is ≥99.9%; based on the total mass of tellurium powder, the mass fraction of tellurium is ≥99.9%; based on the total mass of manganese powder, the mass fraction of manganese is ≥99.9%.

[0055] Example 1

[0056] In this embodiment, a method for preparing a manganese-doped iron selenium telluride superconducting material is provided, comprising the following steps:

[0057] 1) In an argon-protected glove box, iron powder, selenium powder and tellurium powder were weighed and mixed evenly in a molar ratio of iron element, selenium element and tellurium element of 1:0.4:0.6 to obtain a first mixed powder with a total mass of 1.99 g.

[0058] 2) In an argon-protected glove box, the mixed powder was placed in a grinding mortar and ground evenly for 0.5 hours to obtain a first mixed powder after grinding.

[0059] 3) In an argon-protected glove box, the hand-ground powder was placed in a mold with an inner diameter of 0.5 inches, and the powder was pressed into shape using a cold-pressed tablet press at a pressure of 9 MPa for 18 min to obtain a compact.

[0060] 4) In an argon-protected glove box, the compact was placed in a customized quartz tube with a reduced neck and a cylindrical quartz plug was used to clamp the reduced neck. Subsequently, the quartz tube was placed in an argon-protected sealed bag. The quartz tube was taken out and fixed on a tube sealing machine. The quartz tube was evacuated. The gas pressure in the quartz tube was not higher than 5×10 -4 Pa, stop evacuating the tube and use a hydrogen-oxygen torch to seal the quartz plug.

[0061] 5) The quartz tube containing the briquette was treated as follows, and the total treatment time was 57 hours.

[0062] The specific processing is as follows:

[0063] First, the first sintering is performed: the temperature is raised to 500°C for 10 hours and sintered at 500°C for 3 hours;

[0064] Then, multi-stage sintering is performed, and the multi-stage sintering includes four sintering procedures, and the specific steps are:

[0065] The first sintering procedure: heating to 800℃ in 2h, keeping at this temperature for 6h; cooling to 450℃ in 2h, keeping at this temperature for 1h;

[0066] The second sintering procedure: heating to 800℃ for 2h, keeping at this temperature for 6h; cooling to 450℃ for 2h, keeping at this temperature for 1h;

[0067] The third sintering procedure: heating to 800℃ for 2h, keeping at this temperature for 6h; cooling to 450℃ for 2h, keeping at this temperature for 1h;

[0068] The fourth sintering procedure: heating to 800℃ for 2h, keeping at this temperature for 6h; cooling to 450℃ for 2h, keeping at this temperature for 1h;

[0069] After the fourth sintering procedure, the sample was cooled to room temperature to obtain an FeSeTe superconducting bulk.

[0070] 6) In an argon-protected glove box, hand-grind the above-mentioned FeSeTe superconducting block for 0.5 h to obtain FeSeTe superconducting powder, and mix the FeSeTe superconducting powder with manganese powder in a molar ratio of 1:0.02 to obtain a second mixed powder with a total mass of 2 g;

[0071] 7) Repeat steps 2) to 5) with the second mixed powder, and finally cool it to room temperature to obtain the manganese-doped iron-selenium-tellurium superconducting material.

[0072] The photo of the manganese-doped iron-selenium-telluride superconducting material described in this embodiment is shown in FIG. Figure 1 As shown. Figure 2 It can be seen that the manganese-doped iron-selenium-telluride superconducting material has a regular shape, a flat surface, a uniform texture, and no cracks or pores.

[0073] The mass of the manganese-doped iron-selenium-telluride superconducting material is 1.9642 g, the diameter is 12.9 mm, the thickness is 3.27 mm, and the density is 4.598 g / cm 3 , smooth appearance, high density, and meet the requirements of superconducting films and / or superconducting tapes.

[0074] Example 2

[0075] The difference between this embodiment and embodiment 1 is that in step 6), the iron-selenium-tellurium superconducting powder and the manganese powder are uniformly mixed in a molar ratio of 1:0.04.

[0076] The resistance-temperature curve of the manganese-doped iron-selenium-telluride superconducting material described in this embodiment is shown in FIG. Figure 2 As shown. Figure 2 It can be seen that its superconducting transition temperature is 16.52K. Compared with the sample without manganese doping, the superconducting performance of the sample is improved.

[0077] The manganese-doped iron selenium telluride superconducting material described in this embodiment is denoted as FeMn 0.04 Se 0.4 Te 0.6 The X-ray diffraction pattern of the manganese-doped iron selenium telluride superconducting material is as follows: Figure 3 As shown. Figure 3 It can be seen that the manganese-doped iron selenium telluride superconducting material basically does not contain non-superconducting hexagonal phases such as Fe7Se8, and only has superconducting tetragonal phase, and the proportion of superconducting phase is close to 100%. At the same time, compared with the superconducting material without Mn doping, the manganese-doped iron selenium telluride superconducting material is composed of Figure 2 It can be seen that the intensities of the (001), (002), (003) and (004) peaks increase, corresponding to the increase in the texture orientation of the manganese-doped iron selenium telluride superconducting material.

[0078] Example 3

[0079] The difference between this embodiment and embodiment 1 is that in step 6), the iron selenium tellurium superconducting powder and the manganese powder are uniformly mixed in a molar ratio of 1:0.06. The manganese-doped iron selenium tellurium superconducting material prepared in this embodiment is subjected to X-ray diffraction and resistance-temperature detection, and the superconducting transition temperature of the manganese-doped iron selenium tellurium superconducting material in this embodiment is 16.14K. Compared with the sample without manganese doping, the superconducting performance of the sample is improved; the manganese-doped iron selenium tellurium superconducting material basically does not contain non-superconducting hexagonal phases such as Fe7Se8, and only has a superconducting tetragonal phase, and the superconducting phase ratio is close to 100%.

[0080] Example 4

[0081] The difference between this embodiment and embodiment 1 is that in step 1), iron powder, selenium powder and tellurium powder are weighed and mixed evenly in a molar ratio of 1:0.5:0.5 among iron element, selenium element and tellurium element. The manganese-doped iron-selenium-tellurium superconducting material prepared in this embodiment is subjected to X-ray diffraction and resistance-temperature detection, and the superconducting transition temperature of the manganese-doped iron-selenium-tellurium superconducting material in this embodiment is 16.37K. Compared with the sample without manganese doping, the superconducting performance of the sample is improved; the manganese-doped iron-selenium-tellurium superconducting material basically does not contain non-superconducting hexagonal phases such as Fe7Se8, and only has superconducting tetragonal phase, and the proportion of superconducting phase is close to 100%.

[0082] In summary, the present invention discloses a method for preparing a manganese-doped iron-selenium-tellurium superconducting material, which adopts a multi-stage temperature-raising sintering process starting from room temperature, which not only greatly reduces the total sintering time and improves the target material preparation efficiency; but also greatly reduces the volatile vapor pressure of the selenium element through sintering in different temperature ranges, avoids the explosion of the reaction container, and obtains a block with good uniformity and high density; manganese powder is added and heat-treated and sintered, and the manganese powder has the function of catalyzing phase formation, preventing the loss of selenium and tellurium elements, thereby improving the texture orientation of the manganese-doped iron-selenium-tellurium superconducting material, effectively reducing the generation of non-superconducting phases such as Fe7Se8, and improving the superconducting performance.

[0083] The present invention effectively overcomes various shortcomings of the prior art and has high industrial utilization value.

[0084] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A method for preparing a manganese-doped iron selenium telluride superconducting material, characterized in that: The preparation method comprises the following steps: 1) mixing iron powder, selenium powder and tellurium powder to obtain a first mixed powder; 2) grinding the first mixed powder to obtain a ground first mixed powder; 3) pressing the ground first mixed powder to obtain a briquette; 4) performing a first sintering on the compact, then performing a multi-stage sintering, and then cooling the compact to obtain an FeSeTe superconducting block; 5) grinding the FeSeTe superconducting block into FeSeTe superconducting powder, mixing the FeSeTe superconducting powder with manganese powder, Obtaining a second mixed powder; 6) Repeating the operations of steps 2) to 4) with the second mixed powder to obtain a manganese-doped iron-selenium-tellurium superconducting material.

2. The preparation method according to claim 1, characterized in that: The steps 1) to 6) are all carried out under an inert gas atmosphere.

3. The preparation method according to claim 2, characterized in that: The inert gas is selected from one or more of argon, nitrogen and helium.

4. The preparation method according to claim 1, characterized in that: In the step 1), the iron powder, selenium powder and tellurium powder are weighed and mixed in a molar ratio of 1:x:(1-x) among iron element, selenium element and tellurium element, wherein the value of x ranges from 0.3 to 0.7; And / or, in the step 2), the grinding is hand grinding; And / or, in the step 3), the pressure of the pressing treatment is 6 to 10 MPa; And / or, in the step 3), the pressing treatment time is 15-30 minutes.

5. The preparation method according to claim 4, characterized in that: The mass fraction of the iron is ≥ 99.9% based on the total mass of the iron powder; And / or, based on the total mass of selenium powder, the mass fraction of selenium is ≥ 99.9%; and / or, based on the total mass of tellurium powder, the mass fraction of tellurium is ≥ 99.9%; And / or, the hand grinding time is 0.5h to 1h.

6. The preparation method according to claim 1, characterized in that: The step 4) is carried out under vacuum conditions; And / or, in the step 4), the first sintering step includes heating to a sintering temperature and then sintering, the heating time is 3 to 12 hours, the heating rate is 0.5°C / min to 3°C / min, the sintering temperature is 400 to 550°C, and the sintering time is 1 to 5 hours; And / or, in step 4), the multi-stage sintering includes at least two sintering procedures, and the steps of any one of the sintering procedures include: heating for 0.5h to 2h to a temperature of 800°C to 820°C, and keeping the temperature for 5h to 6h; The temperature is lowered for 0.5h to 2h until the temperature reaches 400°C to 430°C, and then kept at this temperature for 0.2h to 1h; the rate of the temperature reduction is 2°C / min to 3°C / min; the rate of the temperature increase is 2°C / min to 3°C / min.

7. The preparation method according to claim 6, characterized in that: The vacuum degree of the vacuum condition is not higher than 5×10 - 4 Pa.

8. The preparation method according to claim 1, characterized in that: In the step 5), the iron-selenium-tellurium superconducting powder and the manganese powder are weighed and mixed in a molar ratio of iron element to manganese element of 1:(0-0.1), and the content of the manganese powder is not 0; And / or, based on the total mass of the manganese powder, the mass fraction of manganese is ≥99.9%.

9. A manganese-doped iron-selenium-telluride superconducting material, characterized in that: The manganese-doped iron-selenium-telluride superconducting material is prepared by the preparation method according to any one of claims 1 to 8.

10. Use of the manganese-doped iron-selenium-telluride superconducting material as claimed in claim 9 in superconducting films and / or superconducting tapes.

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