Dual-Function Ceramic Pigments for Energy-Efficient and Secure Autonomous Vehicles.

The global automobile market continues to demonstrate robust growth and innovation potential. Vehicles have evolved into complex, technology-intensive platforms, and autonomous vehicles are anticipated to become commonplace in the near future. However, key challenges persist, such as managing excessive energy consumption and ensuring precise object detection. Under intense sunlight, elevated in-vehicle temperatures lead to higher demand for cooling systems, ultimately increasing energy use. Furthermore, autonomous driving necessitates accurate detection of surrounding vehicles. To address these issues, doped ceramic pigments with diverse colors are developed, exhibiting enhanced near-infrared (NIR) reflectance across the solar spectrum, thereby achieving a radiative cooling (RC) effect. In addition, to improve detectability by LiDAR, scattering analyses are performed to investigate how ceramic particles scatter incident light in various directions. The results indicate that although the scattering is not strictly retro-reflective, it strongly redirects the incident wave back toward its source, which is advantageous for LiDAR-based object detection. Consequently, a bi-function ceramic pigment (BFCP) is fabricated with both superior RC performance and heightened LiDAR detectability compared to commercial pigments. Moreover, integrating BFCP with commercial pigments enables anti-counterfeiting strategies, as letters or patterns invisible to the naked eye can be visualized under IR-mode cameras.