The large class of layered ceramics encompasses both van der Waals (vdW) and non-vdW solids. While intercalation of noble metals in vdW solids is known, formation of compounds by incorporation of noble-metal layers in non-vdW layered solids is largely unexplored. Here, we show formation of Ti₃AuC₂ and Ti₃Au₂C₂ phases with up to 31% lattice swelling by a substitutional solid-state reaction of Au into Ti₃SiC₂ single-crystal thin films with simultaneous out-diffusion of Si. Ti₃IrC₂ is subsequently produced by a substitution reaction of Ir for Au in Ti₃Au₂C₂. These phases form Ohmic electrical contacts to SiC and remain stable after 1,000 h of ageing at 600 °C in air. The present results, by combined analytical electron microscopy and ab initio calculations, open avenues for processing of noble-metal-containing layered ceramics that have not been synthesized from elemental sources, along with tunable properties such as stable electrical contacts for high-temperature power electronics or gas sensors.

中文翻译：

---

Ti3SiC2中贵金属取代反应的高温稳定欧姆接触SiC的贵金属取代反应合成Ti3AuC2，Ti3Au2C2和Ti3IrC2

大量的层状陶瓷既包含范德华（vdW）固体，也包含非vdW固体。尽管已知贵金属在vdW固体中的嵌入，但在很大程度上尚未探索通过在非vdW层状固体中掺入贵金属层来形成化合物。在这里，我们显示了通过Au置换成Ti ₃ SiC ₂单晶薄膜的固相反应，同时将Al ₃向外扩散，形成了具有高达31％晶格膨胀的Ti ₃ AuC ₂和Ti ₃ Au ₂ C ₂相。硅。Ti ₃ IrC ₂随后通过Ir在Ti ₃ Au ₂ C中置换Au生成。₂。这些相形成了与SiC的欧姆电接触，并 在600  °C的空气中老化1000小时后保持稳定。通过结合分析电子显微镜和从头算计算得出的当前结果为处理尚未从元素源合成的含贵金属层状陶瓷开辟了道路，并提供了可调谐特性，例如用于高温电力电子设备的稳定电触点。或气体传感器。