Employees of the Shanghai University of Science and Technology, in partnership with the Chinese Academy of Sciences, presented a thin-film coating capable of absorbing 99.3% of light. The development has high strength properties and can be used for optical equipment in the aerospace industry.
Unlike current existing carbon nanotube or black silicon coatings, the new development is characterized by higher strength. In addition, equipment manufacturers using analogues may have difficulty applying material inside optical elements due to their complex shape.
To solve this problem, the researchers used atomic layer deposition technology. To implement it, the component is placed in a vacuum chamber and exposed to several types of gases, successively applied to the desired element in the form of thin layers.
The technology makes it possible to evenly distribute the film coating even on very complex surfaces. To create it, the researchers alternately used layers of aluminum-doped titanium carbide (TiAlC) and silicon nitride (SiO2). Together, these two materials are capable of absorbing up to 99.3% of light across a wide range of wavelengths from ultraviolet at 400 nm to near-infrared at 1000 nm.
The created film is so durable that it can withstand friction, heat, humidity and extreme temperature changes. Thanks to this, the new coating can be used to improve the properties of space telescopes and optical equipment in the aerospace industry.