Seven main element high entropy stannate-based negative temperature coefficient thermosensitive material and application

Abstract

The application discloses a series of high-stability negative temperature coefficient thermosensitive materials based on seven main element high-entropy rare earth stannate and application, and aims to solve the problem that existing pyrochlore structure stannate thermosensitive materials cannot meet long-term application under high-temperature environment. The series of thermosensitive materials are prepared by mixing lanthanum trioxide, neodymium trioxide, samarium trioxide, europium trioxide, gadolinium trioxide, dysprosium trioxide and tin dioxide with erbium trioxide or ytterbium trioxide respectively, and the preparation process comprises the following steps: wet three-dimensional vibration ball milling, powder calcination, cold isostatic pressing forming, high-temperature sintering and the like, and finally, the negative temperature coefficient thermosensitive material with the pyrochlore structure is obtained. The electrical performance parameters of the series of materials are as follows: B = 13914-14067 ± 1.89%K, rho 1500℃ = 180.26-204.09 ± 1.38% Omega.cm. The negative temperature coefficient thermosensitive material has the negative temperature coefficient characteristics in a wide temperature range of 400-1500 DEG C, and exhibits excellent high-temperature aging stability under the high-temperature condition of 1500 DEG C; after 500 hours of aging test, the resistance drift rate is only 0.7%.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of semiconductor sensors, especially the field of negative temperature coefficient thermosensitive materials, and in particular to 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 applications. Further, the present application provides a series of high-entropy rare earth stannate negative temperature coefficient thermistor materials, a preparation method thereof, and applications thereof in the field of semiconductor sensors. The thermistor material has typical negative temperature coefficient characteristics, a high upper limit of temperature measurement, and excellent high-temperature aging stability in a wide temperature range of 400-1500°C. BACKGROUND

[0002] In the petroleum chemical industry, metallurgy, aerospace, and energy exploration industries, 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 have become one of the preferred solutions in high-temperature sensing technology due to their high sensitivity, simple structure, low cost, and good electrical stability. Currently, high-temperature thermistor materials commonly used are perovskite structure 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 at high temperatures, making it difficult for the material to sinter into a dense state in air, and second phases are easily generated at the grain boundaries, which makes it extremely challenging for chromate materials to maintain stable performance at high temperatures.

[0003] Pyrochlore-structured ceramic materials are a new type of high-temperature NTC thermistor material in recent years. Compared with perovskite-structured materials, pyrochlore-structured ceramic materials have higher B value and resistivity, thereby meeting the measurement requirements of higher temperature upper limit and ensuring high sensitivity during measurement. The research group of the inventors found that pyrochlore-structured stannate has excellent NTC characteristics and highly linear resistance-temperature relationship in a wide temperature range of 400-1300℃, and its B value exceeds 10000 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, pyrochlore-structured materials usually undergo structural disorder transition after long-term use at high temperature, which in turn causes resistance drift. This not only shortens the service life of these materials as thermistors, but also limits their highest applicable temperature.

[0004] Therefore, improving the high-temperature aging stability of stannate as a thermistor material and expanding its highest measurement temperature are current problems that need to be solved. SUMMARY

[0005] The present application aims to solve the problem that the resistance drift caused by anion sublattice disorderization in the long-term application of existing pyrochlore-structured stannate thermistor materials at high temperature, thereby limiting their application at higher temperature environments, and provides a high-temperature negative temperature coefficient thermistor material based on seven main elements of high-entropy stannate and application. The present 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℃. At the same time, the high-entropy rare earth stannate negative temperature coefficient thermistor material of the present application has a resistance drift rate of less than 1% after aging at 1500℃ for 500 hours, showing excellent aging stability and being suitable for manufacturing high-temperature negative temperature coefficient thermistors with high stability.

[0006] To achieve the above object, the present application adopts the following technical solutions:

[0007] The high-stability negative temperature coefficient thermosensitive material based on seven main elements high-entropy rare earth stannate has a chemical formula of (La 1 / 7Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 RE 1 / 7 )2Sn2O7, wherein RE is one of Er or Yb.

[0008] 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℃.

[0009] The negative temperature coefficient thermosensitive material is prepared by mixing and sintering raw materials of 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.

[0010] The negative temperature coefficient thermosensitive material is prepared by the method comprising the following steps:

[0011] a. According to the substance amount 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, RE oxide 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, then the slurry obtained by wet milling is dried, and then the dried material is ground to obtain a precursor powder; the RE oxide is erbium trioxide or ytterbium trioxide;

[0012] b. The precursor powder obtained in step a is calcined at 1100 ~ 1300℃ for 4 ~ 10 hours, and then the calcined material is ground to obtain pyrochlore phase powder;

[0013] c. The pyrochlore phase powder prepared in step b is pressed into a second shaped block; the second shaped block is subjected to cold isostatic pressing to obtain a third isostatic pressing block; the third isostatic pressing block is placed in a high-temperature environment at 1550 ~ 1650℃ for pressureless sintering for 15 ~ 20 hours to obtain a negative temperature coefficient thermosensitive material.

[0014] In the step a, the weighed lanthanum trioxide, neodymium trioxide, samarium trioxide, europium trioxide, gadolinium trioxide, dysprosium trioxide, RE oxide and tin dioxide are placed in a ball mill jar, agate is used as the ball mill medium, and analytical pure anhydrous ethanol is used as the dispersion medium to conduct 8-12 hours of wet three-dimensional vibration ball milling, and then the slurry obtained by wet milling is dried, and then the dried material is ground to obtain the precursor powder.

[0015] In the step a, the slurry obtained by wet milling is dried at a drying temperature of 50-150°C. Further, in the step a, the drying temperature is 100°C.

[0016] In the step a, the dried material is placed in an agate mortar and manually ground for 2-6 hours to obtain the precursor powder.

[0017] In the step b, the precursor powder obtained in the step a is calcined at 1100-1300°C for 4-10 hours, and then the calcined material is manually ground for 2-4 hours to obtain pyrochlore phase powder.

[0018] In the step c, the pyrochlore phase powder prepared in the step b is briquetted by a single-shaft oil press to obtain a second briquetted body.

[0019] In the step c, the pyrochlore phase powder prepared in the step b is briquetted by a single-shaft oil press to obtain a second briquetted body, and the second briquetted body is subjected to cold isostatic pressing at a pressure of 250-300 MPa for 3 minutes to obtain a third isostatic pressed body.

[0020] In the step c, the third isostatic pressed body is subjected to pressureless sintering at a high temperature of 1550-1650°C for 15-20 hours to obtain the negative temperature coefficient thermosensitive material.

[0021] Application of the aforementioned negative temperature coefficient thermosensitive material.

[0022] The negative temperature coefficient thermosensitive material is used in the field of semiconductor sensors.

[0023] The negative temperature coefficient thermosensitive material is used to manufacture negative temperature coefficient thermosensitive ceramics with the chemical formula (La 1 / 7 Nd 1 / 7Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 RE 1 / 7 )2Sn2O7, wherein RE is Er or Yb.

[0024] In view of the foregoing problems, the application provides a negative temperature coefficient thermosensitive material based on seven main element high-entropy stannate and application. In the application, first, lanthanum trioxide, neodymium trioxide, samarium trioxide, europium trioxide, gadolinium trioxide, dysprosium trioxide and tin dioxide are respectively mixed with erbium trioxide or ytterbium trioxide according to the stoichiometric ratio, ball-milled, dried, powder calcined and secondly ground, and then briquetted, cold isostatic pressed, and sintered at high temperature to obtain the negative temperature coefficient thermosensitive material.

[0025] In the application, the inventors successfully prepared pyrochlore structure high-entropy rare earth stannate ceramic materials which can be applied to the field of high-temperature wide-temperature-range (400-1500℃) negative temperature coefficient thermistors by adopting a new strategy of multi-component design of high-entropy ceramics. It is found that the synergistic effect among the multiple main elements in the high-entropy ceramics can significantly improve the performance of the material. Due to the random distribution of multiple main elements, the local distortion of the crystal lattice is caused, which enhances the carrier scattering effect, and then hinders the migration of carriers, resulting in the increase of the resistivity of the material, which is beneficial to improve the maximum temperature threshold of the application of the thermistor. In addition, due to the significant increase of the configuration entropy of the high-entropy ceramics, the atomic diffusion process in the crystal lattice is delayed, which effectively slows down the possible composition segregation at high temperature, thereby maintaining the long-term thermal stability and structural integrity of the ceramic. The existence of the above characteristics makes the negative temperature coefficient thermosensitive material (the chemical formula of which 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) exhibit excellent aging characteristics at high temperature.

[0026] 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. The thermosensitive material has typical negative temperature coefficient characteristics in the temperature range of 400-1500℃, high upper limit of temperature measurement, good consistency of electrical performance; after aging for 500 hours at 1500℃, the resistance drift rate is less than 1%, the high-temperature electrical stability is high, and the sensitivity is high; it can be seen that the high-entropy rare earth stannate of the application is a high-temperature negative temperature coefficient thermosensitive material suitable for manufacturing high stability.

[0027] The test data show that the thermosensitive material has a single-phase pyrochlore structure, exhibits typical negative temperature coefficient characteristics in a temperature range of 400-1500 DEG C, the high-entropy material has a wide test temperature range, and the upper limit of the highest temperature can reach 1500 DEG C; meanwhile, due to the unique entropy-stable structure, the material exhibits excellent high-temperature aging stability. The negative temperature coefficient thermosensitive material has excellent high-temperature stability, good linear relationship and high consistency, and has a wide application prospect in the field of high-temperature thermosensitive device manufacturing.

[0028] In summary, due to the adoption of the above technical solutions, the application has the following advantages:

[0029] (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) has a single-phase pyrochlore structure;

[0030] (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) has a negative temperature coefficient characteristic in a temperature range of 400-1500 DEG C, has a relatively high upper limit of the test temperature and a relatively wide test temperature range;

[0031] (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) has an electrical resistance drift rate of less than 1% after aging at 1500 DEG C for 500 hours, and exhibits excellent high-temperature aging stability;

[0032] (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) has a relatively high material constant B value at high temperature, which ensures the sensitivity of the material in high-temperature measurement. Attached Figure Description

[0033] The present invention will be described by way of example and with reference to the accompanying drawings, wherein:

[0034] Figure 1 For the present invention (La) 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Er 1 / 7 XRD (X-ray diffraction) pattern of 2Sn2O7 material.

[0035] Figure 2 For the present invention (La) 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Yb 1 / 7 XRD (X-ray diffraction) pattern of 2Sn2O7 material.

[0036] Figure 3 For the present invention (La) 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Er 1 / 7 The resistivity of 2Sn2O7 material versus temperature.

[0037] Figure 4 For the present invention (La) 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Yb 1 / 7 The resistivity of 2Sn2O7 material versus temperature.

[0038] Figure 5 For the present invention (La) 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Er 1 / 7 The relationship between the resistance drift rate of 2Sn2O7 material at 1500℃ and aging time.

[0039] Figure 6 For the present invention (La) 1 / 7 Nd 1 / 7Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Yb 1 / 7 The relationship between the resistance drift rate and the aging time of the (La

[0040] Figure 7 The relationship between the resistivity and the temperature of the (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) material. DETAILED DESCRIPTION

[0041] All of the features disclosed in this specification, and / or all of the steps of any method or process specified in this specification, can be combined in any combination, except combinations where at least some of such features and / or steps are mutually exclusive.

[0042] Any of the features disclosed in this specification, unless explicitly stated otherwise, can be replaced by alternative features serving the same, equivalent or a similar purpose.

[0043] Embodiment 1

[0044] a. According to the substance amount ratio of La:Nd:Sm:Eu:Gd:Dy:Er:Sn = 1:1:1:1:1:1:1:7, the powders of lanthanum trioxide, neodymium trioxide, samarium trioxide, europium trioxide, gadolinium trioxide, dysprosium trioxide, erbium trioxide and tin dioxide are weighed respectively, the oxides are mixed to form an initial mixture; the initial mixture is subjected to wet three-dimensional vibration ball milling for 8 hours; then, the slurry obtained by wet milling is dried at a temperature of 100°C, and the dried material is placed in an agate mortar and manually ground for 6 hours to obtain a precursor powder.

[0045] b. The precursor powder obtained in step a is calcined at 1100°C for 10 hours, and the calcined material is manually ground for 2 hours to obtain pyrochlore phase powder.

[0046] c. The pyrochlore phase powder prepared in step b is formed into a second shaped block by a uniaxial oil press, and then the second shaped block is subjected to cold isostatic pressing forming treatment to obtain a third isostatic pressing block. The third isostatic pressing block is placed in a high-temperature environment at 1550°C and sintered under pressure for 20 hours to obtain (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu1 / 7 Gd 1 / 7 Dy 1 / 7 Er 1 / 7 )2Sn2O7 high-entropy rare earth stannate high-temperature negative temperature coefficient thermosensitive material.

[0047] 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 tested by XRD and electrical properties. The XRD pattern is shown in Figure 1 . Due to the difference in the radius of rare earth cations in high-entropy rare earth stannate, the oxide prepared by multi-principal element co-doping strategy may form a composite with similar structure but various phases after sintering; the specific manifestation of this characteristic on the XRD pattern is the splitting phenomenon of diffraction peaks. However, no splitting phenomenon was observed in the diffraction peaks in Figure 1 , which indicates that the obtained ceramic material is a single-phase pyrochlore structure solid solution. The relationship between resistivity and temperature is 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 aging time of (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7Er 1 / 7 )2Sn2O7 material at 1500℃ was determined, and the test results are shown in Figure 5 . The resistance drift rate is 0.695%.

[0048] Example 2

[0049] a. According to the molar ratio of La:Nd:Sm:Eu:Gd:Dy:Yb:Sn = 1:1:1:1:1:1:1:7, the powders of lanthanum trioxide, neodymium trioxide, samarium trioxide, europium trioxide, gadolinium trioxide, dysprosium trioxide, ytterbium trioxide and tin dioxide were weighed, and the oxides were mixed to form an initial mixture; the initial mixture was subjected to wet three-dimensional vibration ball milling for 12 hours; then, the slurry obtained by wet milling was dried at a temperature of 100℃, and the dried material was placed in an agate mortar and hand ground for 2 hours to obtain a precursor powder.

[0050] b. Calcine the precursor powder obtained in step a at 1300℃ for 4 hours, and then manually grind the calcined material for 4 hours to obtain pyrochlore phase powder.

[0051] c. The pyrochlore phase powder obtained in step b is pressed into blocks using a single-shaft hydraulic press to obtain a second shaped block. Subsequently, this second shaped block undergoes cold isostatic pressing to obtain a third isostatically pressed block. The third isostatically pressed block is then subjected to pressureless sintering at 1650℃ for 15 hours to obtain (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 thermistor material.

[0052] The obtained (La) 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Yb 1 / 7 XRD and electrical properties of the 2Sn2O7 negative temperature coefficient thermistor ceramic material were tested. Figure 2 The XRD pattern shown did not exhibit any splitting of diffraction peaks, indicating that the obtained ceramic material is a single-phase pyrochlore solid solution. The relationship between resistivity and temperature is as follows: Figure 4 As shown, the obtained electrical parameter is 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. Meanwhile, for (La) 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 Yb 1 / 7 The resistivity drift rate of 2Sn2O7 material at 1500℃ was determined in relation to aging time. The test results are as follows: Figure 6 As shown, its resistance drift rate is 0.945%.

[0053] Experimental results show that the single-phase seven-principal-element high-entropy stannate negative temperature coefficient thermistor material prepared by this invention has a wide applicable temperature range, a high upper limit of temperature measurement, good linearity, high measurement sensitivity, and excellent high-temperature aging stability. These properties enable this invention to be applied to higher temperature environments and improve its service life and reliability when used as a thermistor.

[0054] The application is not restricted to the described specific embodiments. The application extends to any novel one, or any new combination, of the features disclosed in this specification, and to any novel method or process disclosed, or any novel combination of the steps of the methods or processes disclosed.

Claims

1. A high stability negative temperature coefficient thermistor material based on seven main element high entropy rare earth stannate, characterized in that, having the chemical formula (La 1 / 7 Nd 1 / 7 Sm 1 / 7 Eu 1 / 7 Gd 1 / 7 Dy 1 / 7 RE 1 / 7 )2Sn2O7, wherein RE is one of Er or Yb; The electrical performance parameters of the negative temperature coefficient thermosensitive material are as follows: B = 13914 ~ 14067 ± 1.89%K, p 1500℃ = 180.26 ~ 204.09 ± 1.38% Omega cm, and the applicable temperature interval is 400 ~ 1500 DEG C; The resistance drift rate of the negative temperature coefficient thermosensitive material is maintained below 1% after aging for 500 hours at 1500℃.

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

3. The material according to any one of claims 1 to 2, wherein the material has a temperature coefficient of resistance of - 0.1 to - 0.

5. The negative temperature coefficient thermosensitive material is prepared by a method comprising the following steps: a. According to a substance amount 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, RE oxide 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, then the slurry obtained by wet milling is dried, and then the dried material is ground to obtain a precursor powder; the RE oxide is erbium trioxide or ytterbium trioxide; b. The precursor powder obtained in step a is calcined at 1100-1300℃ for 4-10 hours, and then the calcined material is ground to obtain pyrochlore phase powder; c. The pyrochlore phase powder prepared in step b is pressed into a second shaped block, and the second shaped block is subjected to cold isostatic pressing to obtain a third isostatic pressing block; the third isostatic pressing block is placed in a high-temperature environment at 1550-1650℃ for pressureless sintering for 15-20 hours to obtain a negative temperature coefficient thermosensitive material.

4. The negative temperature coefficient thermosensitive material according to claim 3, wherein In step a, the weighed lanthanum trioxide, neodymium trioxide, samarium trioxide, europium trioxide, gadolinium trioxide, dysprosium trioxide, RE oxide and tin dioxide are placed in a ball mill jar, and agate is used as the ball milling medium and analytical pure anhydrous ethanol is used as the dispersion medium for wet three-dimensional vibration ball milling for 8-12 hours, then the slurry obtained by wet milling is dried, and then the dried material is ground to obtain a precursor powder.

5. The negative temperature coefficient thermosensitive material according to claim 3, wherein In step b, the precursor powder obtained in step a is calcined at 1200℃ for 4-6 hours, and then the calcined material is manually ground for 2-4 hours to obtain pyrochlore phase powder.

6. The negative temperature coefficient thermosensitive material according to claim 3, wherein In step c, the pyrochlore phase powder prepared in step b is pressed into a second shaped block by using a single-shaft oil press.

7. The negative temperature coefficient thermosensitive material according to claim 3, wherein In step c, the third isostatic pressing block is placed in a high-temperature environment at 1600℃ for pressureless sintering for 15-20 hours to obtain a negative temperature coefficient thermosensitive material.

8. Use of the negative temperature coefficient thermosensitive material according to any one of the preceding claims 1-7.

9. Use according to claim 8, characterized in that, The negative temperature coefficient thermosensitive material is used in the field of semiconductor sensors.

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