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六硼化镧(LaB6)以其低逸出功、高熔点、高电导率、低蒸发率、耐离子轰击能力及稳定的物理化学性质等特点，成为备受关注的电子发射材料，广泛应用于高分辨电子显微镜和电推进系统等领域。LaB6具有简立方晶格结构，La原子位于B6八面体框架中，每个La原子具有3个价电子，其中2个价电子与B原子形成化学键，另外1个价电子相对自由，可以在框架结构内自由穿梭，使得LaB6具有良好的稳定性和优异的电子发射能力。文章详细介绍了多晶和单晶LaB6的制备方法、电子发射性能及性能优化措施，在LaB6应用方面重点介绍了其在电推进领域的应用进展，尤其对近年来国内外电推力器用LaB6空心阴极的最新研究和应用进展进行了总结，并在此基础上分析和展望了LaB6电子发射材料发展存在的技术难点以及未来的研究和应用方向。
Abstract：Lanthanum hexaboride(LaB6), with its low work function, high melting point, high electrical conductivity, low evaporation rate, resistance to ion bombardment, and stable physicochemical properties, has become a widely studied electronic emission material. It has been extensively applied in fields such as highresolution electron microscopes and electric propulsion systems. LaB6 has a simple cubic crystal structure, with La atoms located in the B6 octahedral framework. Each La atom has three valence electrons, two of which form chemical bonds with B atoms, while the remaining valence electron is relatively free and can move freely within the framework. This unique structure gives LaB6 excellent stability and outstanding electron emission capability. This paper provides a detailed introduction to the preparation methods of both polycrystalline and single-crystal LaB6, as well as optimization strategies for its electron emission and mechanical properties. In terms of LaB6 applications, the paper focuses on its progress in the field of electric propulsion, particularly summarizing recent research and applications of LaB6 hollow cathodes in electric thrusters, both domestically and internationally. Based on this, the paper also analyzes and looks forward to the technical challenges in the development of LaB6 electronic emission materials and explores future research and application directions.
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基本信息:
DOI：10.13922/j.cnki.cjvst.202509018
中图分类号:TB34
引用信息:
[1]王一凡,张忻,刘静静,等.LaB_6阴极材料及其在电推进领域应用研究进展[J].真空科学与技术学报,2026,46(03):193-205.DOI:10.13922/j.cnki.cjvst.202509018.
基金信息:
国家自然科学基金项目(52361041;51761018);国家自然科学基金重点项目(U22B20130)
2025-12-15
2025-12-15
2025-12-15