Negative temperature coefficient heat-sensitive material based on seven-principal-element high-entropy stannate and application of negative temperature coefficient heat-sensitive material

Abstract

The invention discloses a series of high-stability negative temperature coefficient heat-sensitive materials based on seven-principal-element high-entropy rare earth stannate and application, and aims to solve the problem that existing stannate heat-sensitive materials with pyrochlore structures cannot meet long-term application in high-temperature environments. The series of heat-sensitive materials are prepared by mixing lanthanum trioxide, neodymium oxide, samarium oxide, europium oxide, gadolinium oxide, dysprosium oxide and tin dioxide with erbium oxide or ytterbium oxide respectively, and the preparation process comprises the steps of wet three-dimensional vibration ball milling, powder calcination, cold isostatic pressing, high-temperature sintering and the like. And finally obtaining the negative temperature coefficient heat-sensitive material with the pyrochlore structure. The electrical property parameters of the series of materials are as follows: B is equal to 13914-14067 + / -1.89% K, and rho 1500 DEG C is equal to 180.26-204.09 + / -1.38% omega.cm. The negative temperature coefficient heat-sensitive material has the negative temperature coefficient characteristic in the wide temperature range of 400-1500 DEG C and shows excellent high-temperature aging stability under the high-temperature condition of 1500 DEG C, and the resistance drift rate of the negative temperature coefficient heat-sensitive material is only 0.7% after an aging test for 500 hours.

Description

Technical Field

[0001] This application relates to the field of semiconductor sensors, especially the field of negative temperature coefficient thermosensitive materials. Specifically, it is a negative temperature coefficient thermosensitive material (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 RE 1 / 7 )2Sn2O7 (RE = Er or Yb) and its applications. Further, this application provides a series of high-entropy rare earth stannate negative temperature coefficient thermistor materials, their preparation methods, and their applications in the field of semiconductor sensors. This thermosensitive material has typical negative temperature coefficient characteristics, a high temperature measurement upper limit, and excellent high-temperature aging stability in a wide temperature range of 400~1500°C. Background Art

[0002] In industries such as petrochemical, metallurgy, aerospace, and energy exploration, temperature monitoring and control in high-temperature environments are crucial. These industries urgently need high-temperature sensors with high precision, long-term stability, and high reliability to meet their complex temperature measurement requirements. Negative temperature coefficient (NTC) thermistors, with their advantages of high sensitivity, simple structure, low cost, and good electrical stability, have become one of the preferred solutions in high-temperature sensing technology. Currently, the common high-temperature thermistor materials are perovskite-structured chromate ceramic materials. However, the material constant (B value) of such materials is usually less than 5000 K, which poses a challenge to their ability to achieve high-sensitivity temperature measurement at higher temperatures and in a wide temperature range. In addition, chromates are prone to element volatilization under high-temperature conditions, making it difficult to sinter the materials into a dense state in air, and prone to side reactions at grain boundaries, precipitating a second phase, which makes it extremely challenging for chromate materials to maintain stable performance at high temperatures.

[0003] Pyrochlore-structured ceramic materials are a newly emerging class of high-temperature NTC thermistor materials in recent years. Compared with perovskite-structured materials, pyrochlore-structured ceramic materials have higher B values and resistivity, thus meeting the measurement requirements of higher temperature limits and ensuring high sensitivity during measurement. The research of the research group where the inventor is located found that pyrochlore-structured stannates have excellent NTC characteristics and a highly linear resistance-temperature relationship in a wide temperature range of 400 - 1300 °C, and their B values exceed 10,000 K (Reference: X.H. Li, X.Y. Chen, Investigation of pyrochlore-type A2Sn2O7(A = La, Nd, Sm, or Gd) ceramics as negative temperature coefficient thermistors for high-temperature application [J], Journal of Physics and Chemistry of Solids, 2023, 175:111205.). However, after long-term use at high temperatures, the structure of pyrochlore-structured materials usually undergoes a disordered transformation, leading to a drift in the resistance value. This not only shortens the service life of these materials as thermistors but also limits their maximum applicable temperature.

[0004] Therefore, improving the high-temperature aging stability of stannates as thermistor materials and expanding their maximum measurement temperature are urgent problems to be solved currently. Summary of the Invention

[0005] The object of the invention of this application is to: aiming at the problem that the resistance drift caused by the disorder of the anion sublattice in the existing pyrochlore-structured stannate thermistor materials during long-term application in a high-temperature environment, which limits their application in a higher temperature environment, provide a high-temperature negative temperature coefficient thermistor material and its application based on hepta-principal high-entropy stannates. This application discloses a high-entropy rare-earth stannate negative temperature coefficient thermistor material (La 1 / 7 Nd 1 / 7 Sm 1 / 7Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 RE 1 / 7 )2Sn2O7 (RE = Er or Yb) with a single-phase pyrochlore structure, which has negative temperature coefficient characteristics in a wide temperature range of 400 - 1500 °C. At the same time, after aging for 500 hours at 1500 °C, the resistance drift rate of the high-entropy rare-earth stannate negative temperature coefficient thermistor material of this application remains below 1%, showing excellent aging stability and being suitable for manufacturing high-stability high-temperature negative temperature coefficient thermistors.

[0006] To achieve the above object, the present invention adopts the following technical solutions: A high-stability negative temperature coefficient thermosensitive material based on hepta-principal element high-entropy rare earth stannate, with the chemical formula (La 1 / 7Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 RE 1 / 7 )2Sn2O7, where RE is one of Er or Yb.

[0007] The electrical performance parameters of the negative temperature coefficient thermosensitive material are as follows: B = 13914~14067 ±1.89%K, ρ 1500℃ = 180.26~204.09 ±1.38% Ω·cm, and the applicable temperature range is 400~1500°C.

[0008] The negative temperature coefficient thermosensitive material is fired by mixing tin dioxide, lanthanum trioxide, neodymium trioxide, samarium trioxide, europium trioxide, gadolinium trioxide, dysprosium trioxide and RE oxide according to the molar ratio of the chemical formula; the RE oxide is erbium trioxide or ytterbium trioxide.

[0009] The negative temperature coefficient thermosensitive material is prepared by a method including the following steps: a. Weigh lanthanum trioxide, neodymium trioxide, samarium trioxide, europium trioxide, gadolinium trioxide, dysprosium trioxide, RE oxide and tin dioxide respectively according to the molar ratio of La:Nd:Sm:Eu:Gd:Dy:RE:Sn = 1:1:1:1:1:1:1:7 to form an initial mixture, where RE = Er or Yb; after wet three-dimensional vibration ball milling the initial mixture for 8~12 hours, dry the slurry obtained by wet milling, and then grind the dried material to obtain a precursor powder; the RE oxide is erbium trioxide or ytterbium trioxide; b. Calcinate the precursor powder obtained in step a at 1100~1300°C for 4~10 hours, and then grind the calcined material to obtain a pyrochlore phase powder; c. Press the pyrochlore phase powder obtained in step b into a block to obtain a second formed block; subject the second formed block to cold isostatic pressing to obtain a third isostatic pressing block; place the third isostatic pressing block in a high-temperature environment of 1550~1650°C for pressureless sintering for 15~20 hours to obtain a negative temperature coefficient thermosensitive material.

[0010] In step a, the weighed lanthanum oxide, neodymium oxide, samarium oxide, europium oxide, gadolinium oxide, dysprosium oxide, RE oxide and tin dioxide are placed in a ball mill pot. Using agate as the ball milling medium and analytical pure anhydrous ethanol as the dispersion medium, wet three-dimensional vibration ball milling is carried out for 8 to 12 hours. Then, the slurry obtained from wet milling is dried, and the dried material is ground to obtain the precursor powder.

[0011] In step a, the slurry obtained from wet milling is dried, and the drying temperature is 50 to 150 °C. Further, in step a, the drying temperature is 100 °C.

[0012] In step a, the dried material is put into an agate mortar and hand-ground for 2 to 6 hours to obtain the precursor powder.

[0013] In step b, the precursor powder obtained in step a is calcined at 1100 to 1300 °C for 4 to 10 hours, and then the calcined material is hand-ground for 2 to 4 hours to obtain the pyrochlore phase powder.

[0014] In step c, a uniaxial hydraulic press is used to press the pyrochlore phase powder prepared in step b into a block to obtain the second formed block.

[0015] In step c, a uniaxial hydraulic press is used to press the pyrochlore phase powder prepared in step b into a block. The forming pressure is 15 to 20 kg / cm², and the forming time is 2 minutes to obtain the second formed block. The second formed block is subjected to cold isostatic pressing and kept at a pressure of 250 to 300 MPa for 3 minutes to obtain the third isostatic pressing block.

[0016] In step c, the third isostatic pressing block is placed in a high-temperature environment of 1550 to 1650 °C for pressureless sintering for 15 to 20 hours to obtain the negative temperature coefficient thermosensitive material.

[0017] Application of the aforementioned negative temperature coefficient thermosensitive material.

[0018] The negative temperature coefficient thermosensitive material is used in the field of semiconductor sensors.

[0019] The negative temperature coefficient thermosensitive material is used to make a negative temperature coefficient thermosensitive ceramic, and its chemical formula is (La 1 / 7 Nd 1 / 7Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 RE 1 / 7 )2Sn2O7, where RE is Er or Yb.

[0020] In view of the foregoing problems, the present application provides a negative temperature coefficient thermosensitive material based on hepta-principal element high-entropy stannate and its application. In the present application, lanthanum trioxide, neodymium trioxide, samarium trioxide, europium trioxide, gadolinium trioxide, dysprosium trioxide and tin dioxide are respectively mixed and ball-milled with erbium trioxide or ytterbium trioxide according to stoichiometric ratios, then dried, calcined for the powder, and ground for the second time. Then, block forming and cold isostatic pressing forming are carried out. The formed material is sintered at high temperature to obtain a negative temperature coefficient thermosensitive material.

[0021] In the present application, the inventors adopted a new strategy of multi-component design of high-entropy ceramics and successfully prepared a pyrochlore-structured high-entropy rare-earth stannate ceramic material that can be applied to the field of negative temperature coefficient thermistors in a high-temperature wide temperature range (400~1500 °C). The research found that the synergistic effect among multiple principal elements in high-entropy ceramics can significantly improve the material properties. Due to the random distribution of multiple principal elements causing local lattice distortion, the carrier scattering effect will be enhanced, thereby hindering the migration of carriers and leading to an increase in the resistivity of the material, which is beneficial to increasing the maximum temperature threshold for thermistor applications. In addition, due to the significant increase in the configurational entropy of high-entropy ceramics, the atomic diffusion process within the lattice is delayed, effectively slowing down the possible compositional segregation at high temperatures, thereby maintaining the long-term thermal stability and structural integrity of the ceramics. The existence of the above characteristics enables the negative temperature coefficient thermosensitive material in the present application (its chemical formula is (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 RE 1 / 7 )2Sn2O7 (RE = Er or Yb)) to exhibit excellent aging characteristics at high temperatures.

[0022] The electrical performance parameters of the high-entropy rare-earth stannate negative temperature coefficient thermosensitive material are as follows: B 400℃ / 1500℃ = 13914~14067 ±1.89% K, ρ 1500℃ = 180.26~204.09 ±1.38% Ω·cm. This thermosensitive material has typical negative temperature coefficient characteristics in the temperature range of 400~1500 °C, with a high temperature measurement upper limit and good electrical performance consistency; after aging at 1500 °C for 500 hours, the resistance drift rate is less than 1%, it is electrically stable at high temperatures and has high sensitivity; it can be seen that the high-entropy rare-earth stannate of the present invention is a negative temperature coefficient thermosensitive material suitable for manufacturing with high stability at high temperatures.

[0023] Test data show that the thermosensitive material of this application has a single-phase pyrochlore structure, exhibits typical negative temperature coefficient characteristics in the temperature range of 400 - 1500 °C. The test temperature range of this high-entropy material is wide, and its highest temperature upper limit can reach 1500 °C. At the same time, due to its unique entropy-stabilized structure, this material shows excellent high-temperature aging stability. The negative temperature coefficient thermosensitive material of this application has excellent high-temperature stability, good linear relationship, and high consistency, and has broad application prospects in the field of manufacturing high-temperature thermosensitive components.

[0024] In summary, due to the adoption of the above technical solutions, the beneficial effects of the present invention are as follows: (1) The thermosensitive material (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 RE 1 / 7 )2Sn2O7 (RE = Er or Yb) of the present invention has a single-phase pyrochlore structure; (2) The thermosensitive material (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 RE 1 / 7 )2Sn2O7 (RE = Er or Yb) of the present invention has negative temperature coefficient characteristics in the temperature range of 400 - 1500 °C, and has a relatively high test temperature upper limit and a relatively wide test temperature range; (3) The thermosensitive material (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 RE 1 / 7 )2Sn2O7 (RE = Er or Yb) of the present invention is aged at 1500 °C for 500 hours, and the resistance drift rate is less than 1%, showing excellent high-temperature aging stability; (4) The thermosensitive material (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 RE 1 / 7 )2Sn2O7 (RE = Er or Yb) of the present invention has a relatively high material constant B value at high temperature, ensuring its sensitivity in high-temperature measurement. Description of the Drawings

[0025] The present invention will be described by way of examples and with reference to the accompanying drawings, wherein: Figure 1 This is the XRD (X-ray diffraction) pattern of the material (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Er 1 / 7 )2Sn2O7 of the present invention.

[0026] Figure 2 This is the XRD (X-ray diffraction) pattern of the material (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Yb 1 / 7 )2Sn2O7 of the present invention.

[0027] Figure 3 This is the graph showing the relationship between the resistivity and temperature of the material (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Er 1 / 7 )2Sn2O7 of the present invention.

[0028] Figure 4 This is the graph showing the relationship between the resistivity and temperature of the material (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Yb 1 / 7 )2Sn2O7 of the present invention.

[0029] Figure 5 This is the graph showing the relationship between the resistance drift rate and aging time of the material (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Er 1 / 7 )2Sn2O7 of the present invention at 1500 °C.

[0030] Figure 6 This is the graph showing the relationship between the resistivity and temperature of the material (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy1 / 7 Ytterbium 1 / 7 Graph of the relationship between the resistance drift rate and aging time of (La

[0031] Figure 7 For the present invention (La 1 / 7 Neodymium 1 / 7 Samarium 1 / 7 Europium 1 / 7 Gadolinium 1 / 7 Dysprosium 1 / 7 Rare earth element (RE) 1 / 7 )2Sn2O7 (where RE = Er or Yb) material as a function of temperature. Detailed implementation methods

[0032] All features disclosed in this specification, or all steps in the disclosed methods or processes, except for mutually exclusive features and / or steps, can be combined in any manner.

[0033] Any feature disclosed in this specification, unless specifically stated, can be replaced by other equivalent or similar-purpose alternative features. That is, unless specifically stated, each feature is only an example of a series of equivalent or similar features.

[0034] Example 1 a. Weigh powders of lanthanum oxide, neodymium oxide, samarium oxide, europium oxide, gadolinium oxide, dysprosium oxide, erbium oxide and tin dioxide respectively according to the molar ratio of La:Nd:Sm:Eu:Gd:Dy:Er:Sn = 1:1:1:1:1:1:1:7. Mix these oxides to form an initial mixture; subject the initial mixture to wet three-dimensional vibration ball milling for 8 hours; then, dry the slurry obtained from wet milling at a temperature of 100 °C, and then put the dried material into an agate mortar and grind it manually for 6 hours to obtain a precursor powder.

[0035] b. Calcinate the precursor powder obtained in step a at 1100 °C for 10 hours, and then grind the calcined material manually for 2 hours to obtain a pyrochlore-phase powder.

[0036] c. Press the pyrochlore-phase powder obtained in step b into a block by a uniaxial oil press to obtain a second formed block. Subsequently, subject the second formed block to cold isostatic pressing to obtain a third isostatic block. Place the third isostatic block in a high-temperature environment of 1550 °C and sinter it without pressure for 20 hours to obtain (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Er 1 / 7) 2Sn2O7 high-entropy rare-earth stannate high-temperature negative temperature coefficient thermosensitive material.

[0037] The obtained (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Er 1 / 7 )2Sn2O7 negative temperature coefficient thermosensitive ceramic materials were subjected to XRD and electrical property tests. Among them, the XRD pattern is as shown in Figure 1 . Due to the differences in the rare-earth cation radii in the high-entropy rare-earth stannate, the oxides prepared by the multi-principal element co-doping strategy may form composites with similar structures but diverse phases after sintering; the specific manifestation of this characteristic on the XRD pattern is the splitting of diffraction peaks. However, observing the diffraction peaks in Figure 1 , no splitting phenomenon was found, indicating that the obtained ceramic material is a solid solution with a single-phase pyrochlore structure. The relationship between resistivity and temperature is as shown in Figure 3 . The obtained electrical parameters are B 400℃ / 1500℃ = 14067 ± 1.57% K, ρ 1500℃ = 204.09 ± 1.24% Ω·cm, and the linear correlation coefficient between lnρ - 1000 / T is 0.9998. At the same time, the relationship between the resistance drift rate and the aging time of the (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7Er 1 / 7 )2Sn2O7 material at 1500 °C was measured, and the test results are as shown in Figure 5 . Its resistance drift rate is 0.695%.

[0038] Example 2 a. According to the molar ratio of La:Nd:Sm:Eu:Gd:Dy:Yb:Sn = 1:1:1:1:1:1:1:7, powders of lanthanum oxide, neodymium oxide, samarium oxide, europium oxide, gadolinium oxide, dysprosium oxide, ytterbium oxide and tin dioxide were weighed respectively. These oxides were mixed to form an initial mixture; the initial mixture was subjected to wet three-dimensional vibration ball milling for 12 hours; subsequently, the slurry obtained by wet milling was dried at a temperature of 100 °C, and then the dried material was put into an agate mortar and hand-ground for 2 hours to obtain a precursor powder.

[0039] b. The precursor powder obtained in step a was calcined at 1300 °C for 4 hours, and then the calcined material was hand-ground for 4 hours to obtain a pyrochlore phase powder.

[0040] c. Compress the pyrochlore-phase powder obtained in step b into a block by a uniaxial hydraulic press to obtain a second formed block. Subsequently, subject the second formed block to cold isostatic pressing to obtain a third isostatic pressing block. Place the third isostatic pressing block in a high-temperature environment of 1650 °C and sinter it without pressure for 15 hours to obtain a (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Yb 1 / 7 )2Sn2O7 high-entropy rare-earth stannate high-temperature negative temperature coefficient thermosensitive material.

[0041] Perform XRD and electrical property tests on the obtained (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Yb 1 / 7 )2Sn2O7 negative temperature coefficient thermosensitive ceramic material. As shown in the Figure 2 XRD pattern, no splitting of diffraction peaks is observed. This result indicates that the obtained ceramic material is a solid solution with a single-phase pyrochlore structure. The relationship between resistivity and temperature is as shown in Figure 4 . The obtained electrical parameters are B 400℃ / 1500℃ = 13914 ± 1.89% K, ρ 1500℃ = 180.26 ± 1.38% Ω·cm, and the linear correlation coefficient between lnρ - 1000 / T is 0.9997. At the same time, measure the relationship between the resistance drift rate and the aging time of the (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Yb 1 / 7 )2Sn2O7 material at 1500 °C. The test results are as shown in Figure 6 . Its resistance drift rate is 0.945%.

[0042] The test results show that the single-phase hepta-principal high-entropy stannate negative temperature coefficient thermistor material prepared by the present invention has a wide applicable temperature range, a high temperature measurement upper limit, good linearity, high measurement sensitivity, and excellent high-temperature aging stability; these properties enable the present invention to be applied to a higher temperature environment and improve its service life and reliability when used as a thermistor.

[0043] The present invention is not limited to the foregoing specific embodiments. The present invention extends to any new feature or any new combination disclosed in this specification, as well as to any new method or process step or any new combination disclosed.

Claims

1. A high-stability negative temperature coefficient thermistor material based on seven-principal-element high-entropy rare earth stannate, characterized in that: Its chemical formula is (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 G 1 / 7 Dy 1 / 7 RE 1 / 7 )2Sn2O7, wherein RE is one of Er or Yb.

2. The negative temperature coefficient thermistor material according to claim 1, characterized in that: The electrical performance parameters of the negative temperature coefficient thermistor material are as follows: B = 13914 ~ 14067 ± 1.89% K, ρ 1500℃ =180.26~204.09 ±1.38% Ω·cm, applicable temperature range is 400~1500℃.

3. The negative temperature coefficient thermistor material according to claim 1 or 2, characterized in that: The negative temperature coefficient thermistor is prepared by mixing and sintering raw materials of tin dioxide, lanthanum trioxide, neodymium trioxide, samarium trioxide, europium trioxide, gadolinium trioxide, dysprosium trioxide and oxide of RE according to a chemical formula molar ratio; the oxide of RE is erbium trioxide or ytterbium trioxide.

4. The negative temperature coefficient thermistor material according to any one of claims 1 to 3, characterized in that: The negative temperature coefficient thermistor material is prepared by a method comprising the following steps: a. According to the molar ratio of La:Nd:Sm:Eu:Gd:Dy:RE:Sn=1:1:1:1:1:1:1:7, lanthanum trioxide, neodymium trioxide, samarium trioxide, europium trioxide, gadolinium trioxide, dysprosium trioxide, oxides of RE and tin dioxide are respectively weighed and mixed to form an initial mixture, RE=Er or Yb; the initial mixture is subjected to wet three-dimensional vibration ball milling for 8-12 hours, and then the slurry obtained by wet milling is dried, and then the dried material is ground to obtain a precursor powder; the oxide of RE is erbium trioxide or ytterbium trioxide; b. calcining the precursor powder obtained in step a at 1100-1300° C. for 4-10 hours, and then grinding the calcined material to obtain a pyrochlore phase powder; c. Pressing the pyrochlore phase powder obtained in step b into a block to obtain a second molded block; cold isostatically pressing the second molded block to obtain a third isostatically pressed block; and placing the third isostatically pressed block in a high temperature environment of 1550-1650° C. for pressureless sintering for 15-20 hours to obtain a negative temperature coefficient thermistor material.

5. The negative temperature coefficient thermistor material according to claim 4, characterized in that: In the step a, the weighed lanthanum trioxide, neodymium trioxide, samarium trioxide, europium trioxide, gadolinium trioxide, dysprosium trioxide, oxide of RE and tin dioxide are placed in a ball mill, agate is used as the ball milling medium, and analytical pure anhydrous ethanol is used as the dispersion medium. The wet three-dimensional vibration ball milling is performed for 8 to 12 hours, and the slurry obtained by wet milling is dried, and then the dried material is ground to obtain a precursor powder.

6. The negative temperature coefficient thermistor material according to claim 4, characterized in that: In the step b, the precursor powder obtained in the step a is calcined at 1200° C. for 4 to 6 hours, and the calcined material is then manually ground for 2 to 4 hours to obtain a pyrochlore phase powder.

7. The negative temperature coefficient thermistor material according to any one of claims 4 to 6, characterized in that: In the step c, the pyrochlore phase powder obtained in the step b is pressed into blocks using a uniaxial hydraulic press to obtain a second formed block.

8. The negative temperature coefficient thermistor material according to claim 4, characterized in that: In the step c, the third isostatically pressed block is placed in a high temperature environment of 1600° C. for pressureless sintering for 15 to 20 hours to obtain a negative temperature coefficient thermistor material.

9. Use of the negative temperature coefficient thermistor material according to any one of claims 1 to 8.

10. The use according to claim 9, characterized in that: The negative temperature coefficient thermistor material is used in the field of semiconductor sensors.

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