 Carbon aerogels are also extremely "black" in the infrared spectrum, reflecting only 0.3% of radiation between 250 nm and 14.3 µm, making them efficient for solar energy collectors.The term "aerogel" to describe airy masses of carbon nanotubes produced through certain chemical vapor deposition techniques is incorrect.Such materials can be spun into fibers with strength greater than Kevlar, and unique electrical properties.