Bioinspired Porous Anodic Alumina/Aluminum Flake Powder for Multiband Compatible Low Detectability

Continuous development and advancement in modern detection technologies have increased the demand for multiband (e.g., visual and infrared) compatible camouflage. However, challenges exist in the requirements of incompatible structure resulting from the adaptation to different camouflage effects. This study is inspired by the light absorption structure of butterfly wing scales and demonstrates a porous anodic alumina/aluminum flake powder material prepared by a microscopic powder anodic oxidation technique for visual and infrared camouflage. The fabricated structures manipulate a compromise condition for visual camouflage by low reflectance (R̅_400-800nm = 0.32) and dual-band infrared camouflage by low emission (ε̅_3-5μm = 0.081 and ε̅_8-14μm = 0.085). Further, the characteristic of short-range disorder in these bioinspired structures allows maintenance of the camouflage performance under omnidirectional detection (0-60°). This study provides new insight and a feasible method for coordinated manipulation of electromagnetic waves via bioinspired structural design and improved fabrication.