Scientists at Zhejiang University in China developed an ultra-light material known as carbon aerogel, with a density of just 0.16 milligrams per cubic centimeter—one-sixth the density of air.

Carbon Aerogel: The Material Lighter Than Air

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Imagine holding a material so light it makes air look heavy. That's exactly what Professor Gao Chao and his team at Zhejiang University accomplished when they created carbon aerogel—a substance with a density of just 0.16 milligrams per cubic centimeter. To put that in perspective, it's one-sixth the density of air and only twice as dense as hydrogen gas.

Often called "frozen smoke" due to its ghostly appearance, this carbon aerogel is made from graphene and carbon nanotubes using an innovative freeze-drying technique. The result? A spongy material that's 99.9% air, yet maintains structural integrity.

Lighter Than Helium Balloons

The aerogel is actually lighter than helium—yes, the stuff that makes balloons float. If you placed a chunk of it on a delicate flower, the petals wouldn't even bend under its weight. Scientists demonstrated this by balancing pieces on wheat stalks and flower blooms without causing any visible deformation.

A Sponge on Steroids

Despite being incredibly light, carbon aerogel has remarkable absorption capabilities:

  • Can absorb up to 900 times its own weight in oils and organic solvents
  • Highly elastic—compress it, and it bounces back to its original shape
  • Can be molded into any shape during manufacturing
  • Remains stable even when saturated with liquids

These properties make it ideal for environmental cleanup, particularly oil spill remediation where traditional methods struggle.

From Ocean Cleanup to Outer Space

The team didn't stop at creating the world's lightest material. In 2025, they published research in Science detailing an advanced version that can withstand temperatures exceeding 2000°C while maintaining its elastic properties.

This ultra-high-temperature aerogel features a unique micro-dome cellular structure that stays resilient under extreme compression and heat. Potential applications include:

  • Deep-space probes requiring lightweight thermal insulation
  • Hypersonic aircraft experiencing extreme atmospheric friction
  • Nuclear fusion devices operating at stellar temperatures
  • Protective equipment for firefighters and industrial workers

The Future Is Lighter Than Air

What makes carbon aerogel truly revolutionary isn't just its record-breaking lightness—it's the combination of properties that seemed impossible in a single material. Ultra-lightweight, super-absorbent, heat-resistant, and elastic—it's the kind of material that sounds like science fiction.

As research continues, we might see carbon aerogel in everything from advanced spacecraft to everyday products. One thing's certain: when scientists create materials lighter than the air we breathe, the sky is no longer the limit.

Frequently Asked Questions

What is carbon aerogel made of?
Carbon aerogel is made from graphene and carbon nanotubes using a freeze-drying process. It's 99.9% air by volume, with the remaining structure formed by interconnected carbon materials.
How light is carbon aerogel compared to air?
Carbon aerogel has a density of 0.16 milligrams per cubic centimeter, making it six times lighter than air. It's even lighter than helium gas.
What can carbon aerogel be used for?
Carbon aerogel can be used for oil spill cleanup (absorbing 900 times its weight), thermal insulation in spacecraft, heat protection in hypersonic aircraft, and applications requiring ultra-lightweight materials that withstand extreme temperatures.
Who invented carbon aerogel?
Professor Gao Chao and his team at Zhejiang University in China developed the ultra-light carbon aerogel in 2013, with continued breakthroughs including a 2025 version that withstands temperatures over 2000°C.
Is carbon aerogel the lightest material in the world?
At the time of its creation in 2013, Zhejiang University's carbon aerogel was recognized as the world's lightest material, with newer versions continuing to push the boundaries of ultra-lightweight materials science.

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