Graphene "balloons" endure extreme pressure and could help evaluate other materials

Researchers at The University of Manchester have shown that small "balloons" made using graphene can endure huge pressures. This could be used to create miniature pressure machines that can withstand massive pressures, and pose a major step towards quickly identifying the way molecules respond under extreme pressure.

The graphene balloons normally form when depositing graphene on flat substrates and are typically thought of as a useless. The researchers at Manchester observed the nano-bubbles closely and discovered that the dimensions and shape of the nano-bubbles offer direct data regarding the elastic strength of graphene as well as its interaction with the underlying substrate. They were able to measure the pressure applied by graphene on a material caught within the balloons, or vice versa.

To achieve this, the team indented bubbles made by graphene, monolayer boron nitride, and monolayer MoS2 using a tip of an atomic force microscope, and measured the force that was essential to make a dent of a specific size. These measurements exposed the fact that graphene enclosing bubbles of a micron size form pressures reaching as high as 200 MPa, or 2,000 atmospheres. Much higher pressures are anticipated for smaller bubbles.

They also discovered that these types of balloons can be formed using other 2D crystals, such as single layers of boron nitride or molybdenum disulfide (MoS2).

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Posted: Aug 26,2016 by Roni Peleg