【摘要】 范德华(vdW)异质结构凭借其独特的光学、电学与热学特性成为研究热点，在光催化、超快光子学及自由电子辐射器件等领域展现出巨大应用潜力，更是探索热电子发射机制的理想平台。文章证实，基于范德华异质结构的热电子发射技术可显著提升真空器件的传热效率。作为概念验证，该技术为攻克X射线管长期存在的过热难题提供了极具前景的解决方案——实验表明，2 000 W X射线管的饱和靶温可从约1 200°C大幅降至490°C。此外，研究还发现，通过调控范德华异质结构中的肖特基势垒高度，可有效增强热电子冷却性能。我们的研究为发展高功率X射线管铺平了道路。更多还原

【Abstract】 Van der Waals(vdW) heterostructures have attracted much attention due to their distinctive optical,electrical, and thermal properties, demonstrating promising potential in areas such as photocatalysis, ultrafast photonics, and free electron radiation devices. Particularly, they are promising platforms for studying thermionic emission. It is illustrated that using vd W heterostructure-based thermionic emission can enhance heat transfer in vacuum devices. As a proof of concept, the approach is demonstrated to offer a promising solution for the long-standing overheating issue in X-ray tubes. Specifically, it is shown that the saturated target temperature of a 2000 W X-ray tube can be reduced from around 1200 °C to 490 °C. Additionally, it is also demonstrated that by reducing the height of the Schottky barrier formed in the vd W heterostructures, the thermionic cooling performance can be enhanced. The findings pave the way for the development of high-power X-ray tubes.更多还原