Researchers at Brown University have demonstrated that graphene, wrinkled and crumpled in a multi-step process, becomes significantly better at repelling water - a property that could be useful in making self-cleaning surfaces. Crumpled graphene also has enhanced electrochemical properties, which could make it more useful as electrodes in batteries and fuel cells.
The researchers aimed to build relatively complex architectures incorporating both wrinkles and crumples. To do that, the researchers deposited layers of graphene oxide onto shrink films -polymer membranes that shrink when heated. As the films shrink, the graphene on top is compressed, causing it to wrinkle and crumple. To see what kind of structures they could create, the researchers compressed same graphene sheets multiple times. After the first shrink, the film was dissolved away, and the graphene was placed in a new film to be shrunk again.