CN-117776692-B - High-entropy perovskite type high-temperature negative temperature coefficient thermosensitive ceramic, preparation method and application

Abstract

The application provides a high-entropy perovskite type high-temperature negative temperature coefficient thermal ceramic, a preparation method and application thereof, which belong to the field of perovskite type semiconductor materials, wherein the series of high-temperature negative temperature coefficient thermal ceramic is prepared by mixing lanthanum oxide, neodymium oxide, samarium oxide, europium oxide and chromium oxide with oxides of A respectively, carrying out wet three-dimensional vibration ball milling, powder calcination, cold isostatic pressing and high-temperature sintering to obtain a perovskite structure (La 0.2 Nd 0.2 Sm 0.2 Eu 0.2 A 0.2 )CrO 3 thermal ceramic, wherein A is one of Pr, tb, dy, ho, er, yb, lu, Y).

Inventors

• GAO BO
• CHEN XIAOYI
• KONG WENWEN
• CHEN CHAOYANG

Assignees

• 中国科学院新疆理化技术研究所

Dates

Publication Date

20260512

Application Date

20231113

Claims (5)

1. 1. The high-entropy perovskite type high-temperature negative temperature coefficient thermosensitive ceramic is characterized in that the chemical formula of the ceramic is (La 0.2 Nd 0.2 Sm 0.2 Eu 0.2 A 0.2 )CrO 3 , wherein A is one of Pr, tb, dy, ho, er, yb, lu, Y; The electrical performance parameters of the high-entropy perovskite type high-temperature negative temperature coefficient thermal ceramic are as follows, B 25℃/1500℃ =1625~1742 K,ρ 1500℃ =7.48~7.75×10 2 omega cm, and the applicable temperature range is 25-1500 ℃; The high-entropy perovskite type high-temperature negative temperature coefficient thermal ceramic is prepared by adopting a method comprising the following steps of: a. Weighing oxide powder lanthanum oxide, neodymium oxide, samarium oxide, europium oxide, oxide of A and chromium oxide respectively according to the mass ratio of La, nd, sm and Eu to Cr=1:1:1:1:5, mixing to obtain an initial mixture, carrying out wet three-dimensional vibration ball milling on the initial mixture for 8-11 hours, drying the wet slurry, taking out, and manually grinding in an agate mortar for 1-5 hours to obtain precursor powder; b. Calcining the precursor powder obtained in the step a for 3-20 hours at 1100 ℃, and manually grinding for 0.5-10 hours to obtain perovskite phase powder; c. And C, briquetting the perovskite phase powder obtained in the step b by using a single-shaft oil press to obtain a second formed block, performing cold isostatic compaction on the second formed block to obtain a third isostatic pressing block, and sintering the third isostatic pressing block at 1600 ℃ for 15-20 hours to obtain the high-entropy rare earth chromate high-temperature negative temperature coefficient heat-sensitive material.
2. 2. The high-entropy perovskite type high-temperature negative temperature coefficient thermal sensitive ceramic according to claim 1, wherein in the step a, according to the mass ratio of La, nd, sm, eu, cr=1:1:1:1:5, the oxides of oxide powder lanthanum oxide, neodymium oxide, samarium oxide, europium oxide and A and chromium oxide are weighed and mixed, the mixture is placed in a ball milling tank, agate is taken as a ball milling medium, analytically pure absolute ethyl alcohol is taken as a dispersing medium, wet three-dimensional vibration ball milling is carried out for 8-11 hours, the wet-milled slurry is dried at the temperature of 100-150 ℃, and the wet-milled slurry is taken out and is manually milled in an agate mortar for 2-5 hours, so that precursor powder is obtained.
3. 3. The high-entropy perovskite type high-temperature negative temperature coefficient thermal ceramic according to claim 1, wherein in the step b, the precursor powder obtained in the step a is calcined at 1100 ℃ for 5-10 hours, and then is manually ground for 2 hours, so as to obtain perovskite phase powder.
4. 4. The use of a high entropy perovskite type high temperature negative temperature coefficient thermal ceramic according to any one of the preceding claims 1 to 3.
5. 5. The use according to claim 4, wherein the high-entropy perovskite type high-temperature negative temperature coefficient thermal ceramic is used in the field of semiconductor sensors, and has a chemical formula (La 0.2 Nd 0.2 Sm 0.2 Eu 0.2 A 0.2 )CrO 3 , a is one of Pr, tb, dy, ho, er, yb, lu, Y).

Description

High-entropy perovskite type high-temperature negative temperature coefficient thermosensitive ceramic, preparation method and application Technical Field The invention relates to the field of materials, in particular to the field of perovskite type semiconductor materials, in particular to high-entropy perovskite type high-temperature negative temperature coefficient thermal sensitive ceramic, a preparation method and application (La 0.2Nd0.2Sm0.2Eu0.2A0.2)CrO3 (A= Pr, tb, dy, ho, er, yb, lu, Y)), and more particularly provides a high-entropy rare earth chromate-based high-temperature negative temperature coefficient thermal sensitive material, a preparation method of the ceramic and application of the ceramic as a semiconductor material. Background Sensor technology is the leading edge technology of modern technology, is one of three major posts of modern information technology, and the level is one of important marks for measuring the state of technology development. The sensitive components and the sensor are basic products in the electronic information manufacturing industry, and are special components in novel electronic components which are developed mainly in fifteen or even 12-20 years in the future. Temperature is one of the most basic thermodynamic physical parameters, and its measurement and control are critical in scientific research, industrial production and daily life. In recent years, with the rapid development and breakthrough of China in various fields such as Internet of things, big data, cloud computing technology, smart city and the like, the demand for sensor technology is also huge. In the field of semiconductor device technology, negative temperature coefficient thermistors, i.e., NTC (negative temperature coefficient ) thermistors, have resistance values that decrease exponentially as temperature increases. As the NTC thermistor has the advantages of low cost, quick response, high measurement accuracy and the like, the NTC thermistor is widely applied to the aspects of temperature measurement, temperature control, temperature compensation, surge current suppression and the like. The material constant B of the NTC thermistor characterizes the sensitivity of the NTC thermistor to temperature, and the larger the B value is, the larger the change rate of the resistance of the NTC thermistor to temperature is, and the better the sensitivity of the material to temperature is. The common thermosensitive ceramic material is prepared by taking Mn, fe, co, ni and other transition metal oxides doped with partial rare earth metal oxides as raw materials and adopting the traditional semiconductor ceramic process. Different system materials are selected, the formula proportion and the preparation process (sintering atmosphere, presintering temperature, sintering temperature, heat preservation time and the like) are regulated, NTC thermosensitive materials with different resistivity and B values can be obtained, and thus thermosensitive resistor devices meeting different requirements are obtained. With the rapid development of technology, under the trend of integration and intellectualization of electronic equipment, the spinel type thermal ceramic resistor which is commonly used cannot completely meet the requirements of practical application. Therefore, there is an urgent need to develop a novel thermistor suitable for use at higher temperatures and with higher accuracy and suitable for wide temperature range applications. NTC thermistor materials of perovskite structure have received a great deal of attention due to their suitability at high temperatures. How to further improve the performance of the perovskite type NTC thermistor becomes a hot spot for people to study. Disclosure of Invention The invention aims to provide high-entropy perovskite type high-temperature negative temperature coefficient thermosensitive ceramic, a preparation method and application. In order to achieve the above purpose, the present invention adopts the following technical scheme: the chemical formula of the high-entropy perovskite type high-temperature negative temperature coefficient thermal sensitive ceramic is (La 0.2Nd0.2Sm0.2Eu0.2A0.2)CrO3, wherein A is one of Pr, tb, dy, ho, er, yb, lu, Y. The negative temperature coefficient thermosensitive material is prepared by mixing and firing raw materials of lanthanum oxide, neodymium oxide, samarium oxide, europium oxide and chromium oxide respectively with oxides of A. The oxide of A is Pr, tb, dy, ho, er, yb, lu, Y. Wherein A is one of Pr, tb, dy, ho, er, yb, lu, Y. The oxide of A is praseodymium oxide, terbium oxide, dysprosium oxide, holmium oxide, erbium oxide, ytterbium oxide, lutetium oxide and yttrium oxide. The series of negative temperature coefficient thermosensitive materials are prepared by mixing and firing raw materials of lanthanum oxide, neodymium oxide, samarium oxide, europium oxide and chromium oxide respectively with praseodymium oxide, terbium