Scientists Say: 2-D Material

Just one or two atoms thick, these materials have a wide range of potentially useful properties

Graphene, shown in this illustration, is a layer of carbon atoms that is only one atom thick — yet graphene is super-strong, super-light and is a superstar at conducting electricity.

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2-D material (noun, “Too-dee Muh-TEE-ree-uhl”)

So-called two-dimensional, or 2-D, materials are super flat. These materials are not literally two-dimensional. They have length, width and height. But they’re just one or two atoms thick. So their height is practically zero. Hence: 2-D material.

Graphene is the most famous of these materials. But there are many other 2-D materials with a wide range of useful properties.

Graphene is a single layer of carbon atoms bonded together. It’s super strong, lightweight and flexible. That could make it useful for making small, bendy electronics. Or it could be help strengthen cement, shield against mosquito bites and much more.

Phosphorene is much like graphene. But instead of carbon atoms, it’s made of phosphorus atoms. This gives the material different electrical properties. Graphene is a conductor. That is, electricity flows through it easily. But phosphorene is a semiconductor. Electrical current flowing through it can be turned on or off. This could make phosphorene useful for building next-generation electronics.

Hexagonal boron nitride is another 2-D material. But it’s made with boron and nitrogen atoms. It reflects ultraviolet light and is good at shedding heat. That recently made it the key ingredient for a “thermal cloak” that can help control the temperatures inside cars.

Graphitic carbon nitride is a 2-D material made up of carbon and nitrogen. Under light, it releases chemicals that destroy germs to purify water. And a class of 2-D materials called MXenes are great at snatching carbon dioxide out of the air. In the future, they could help pull climate-warming CO2 out of the atmosphere.

Still other 2-D materials contain different types of atoms arranged in many different ways — giving rise to a whole range of properties useful for a wide range of applications.

In a sentence

2-D materials called MXenes could also be used to make better batteries or other energy storage devices.

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Maria Temming is the Assistant Managing Editor at Science News Explores. She has bachelor's degrees in physics and English, and a master's in science writing.