Rare earth hexaborides are one of the six-membered compounds composed of rare earth and boron elements, and they possess significant physical and chemical properties. In recent years, the research on rare earth hexaborides has received extensive attention. This article aims to introduce its research progress, including the preparation methods, physicochemical properties, and applications in electronic devices, optoelectronic devices, and other aspects of rare earth hexaborides.

I. Preparation Methods of Rare Earth Hexaborides

The preparation methods of rare earth hexaborides mainly include thermal reaction method, chemical vapor deposition method, solvothermal method, etc. Among them, the thermal reaction method is one of the most commonly used preparation methods. Take LaB6 as an example. LaB6 can be obtained by reacting LaCI3 with B4C at high temperatures. Chemical vapor deposition is another commonly used preparation method, which is characterized by the ability to precisely control the crystal structure, morphology and size of rare earth hexaborides. The solvothermal method is a technique that involves mixing rare earth metal salts with boric acid or borates in an organic solvent and then pyrolyzing them at high temperatures to obtain rare earth hexaborides.

Ii. Physical and Chemical Properties of Rare Earth hexaborides

The physicochemical properties of rare earth hexaborides have certain regularity and particularity. Firstly, the crystal structure of rare earth hexaborides is usually a non-simple cubic structure. For instance, the crystal structure of LaB6 is face-centered cubic fcc. Secondly, in the selection of rare earth elements, the electron orbital distribution and valence electron state of rare earth ions have significant influences on the structure and properties of rare earth hexaborides. For instance, NdB6 has a higher melting point and hardness than LaB6. Furthermore, studies in optical, electrical and thermoelectric physical properties have shown that rare earth hexaborides have excellent optical absorption, electrical conductivity and thermoelectric performance.

Iii. Application of Rare Earth Hexaborides in Electronic Devices

The application of rare earth hexaborides in electronic devices is very extensive, mainly manifested in two aspects. First, rare earth hexaborides themselves can be used as electrode materials and high-temperature materials; The second is the combination of rare earth hexaborides with other materials, such as the combination of rare earth hexaborides with semiconductors.

In terms of stability and thermal stability, rare earth hexaborides have excellent thermal stability, with a very high melting point and hardness. Therefore, it has great application potential in high-temperature environments, such as high-temperature resistors and thermal resistance materials. In addition, rare earth hexaborides themselves have good electrical conductivity and can be used as electrode materials. Therefore, its application in microelectronic devices also holds great prospects.

Iv. Application of Rare Earth Hexaborides in Optoelectronic Devices

The application of rare earth hexaborides in optoelectronic devices is mainly manifested in the aspects of optical, thermal and electrical properties. Due to the excellent optical absorption properties of rare earth hexaborides themselves, they can be used in fields such as light detection and photovoltaics, for instance, in the application of solar cells. In addition, the optical nonlinear effect based on rare earth hexaborides also shows strong application potential, such as wavelength converters in optical fiber communications.

Conclusion

Rare earth hexaborides are a very important type of compound and have broad application prospects. The research on its preparation methods and physicochemical properties has been very mature. The crystal structure and properties can be regulated and optimized by means of controlling the selection of raw materials, reaction conditions, etc. In the fields of electronic devices, optoelectronic devices, etc., the application potential of rare earth hexaborides is huge. They can not only improve the performance and stability of devices, but also explore new physical and chemical phenomena, playing an important role in promoting the progress of science and technology.