Femtosecond laser based “Janus-material/function” processing paradigm for photothermal and radiative cooling modulation
基于飞秒激光的“Janus材料/功能”光热和辐射冷却调制加工范式
フェムト秒レーザーに基づく「Janus材料/機能」光熱と放射冷却の変調処理モデル
광열 및 방사선 냉각 조절을 위한 페페트토초 레이저 기반 "Janus-material/function" 처리 패러다임
Paradigma de procesamiento “Janus-material/función” basado en láser de femtosegundos para modulación de enfriamiento fototérmico y radiativo
Paradigme de traitement "Janus-matériau/fonction" basé sur le laser femtoseconde pour la modulation de refroidissement photothermique et radiatif
Фемтосекундная лазерная парадигма обработки «Янус-материал/функция» для модуляции фототермального и радиационного охлаждения
Jianing Liao ¹, Zhuguo Li ¹ ², Dongshi Zhang ¹
¹ Shanghai Key Laboratory of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
中国 上海 上海交通大学材料科学与工程学院 激光制造与材料改性重点实验室
² State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
中国 上海 上海交通大学材料科学与工程学院 金属基复合材料国家重点实验室
The “Janus” concept, integrating asymmetric functions like radiative cooling (RC) and photothermal (PT) effects is gaining prominence for multi-scenario applications and function enhancement. In this work, we present a novel “Janus-material/function” processing paradigm by femtosecond laser nanomaterial synthesis and 600 °C thermal post annealing.
This technique enables universal preparation of PT-active surfaces and in situ colorful RC functional transitions on transition metals (Nb, Mo, Ta, and W), while Ti-based PT interfaces exhibit uniquely thermal resistantance. Using custom-built systems, the PT/RC effects of as-prepared “Janus” black/white PT/RC-WO3−x interfaces are verified, with interfacial temperatures 2 °C lower and 9 °C higher, respectively, than that of the benchmark tungsten plate under 1-sun irradiation.
These interfaces demonstrate good thermal/mechanical stabilities, withstanding 4 h of 100 °C/200 °C annealing, vigorous hand shaking, and tape peeling. Femtosecond laser in situ PT-WO3−x patterning on high-thermal-conductivity, high-infrared-reflective W-substrate demonstrates high-contrast infrared display in the emission and reflection modes by 80 °C sample heating and hot water excitation, respectively; whereas annealed white/dark-blue RC-PT-WO3−x matrix, characterized by low thermal conductivities, exhibits convergent low-contrast infrared display.
The flexibility of this paradigm, enabling convenient integration of double-sided “Janus” PT-RC functionalization and single-sided PT-RC “LASER JANUS” patterning on a single refractory metal, highlighting its potential for advanced Janus-conceptional customization in different thermal regulation scenarios.
