The team found that a multigenerational approach – the application of several shrinking processes – could compress the graphene sheets substantially, as well as creating ‘interesting patterns’.
Apparently, how the crumpling is produced is an important factor. Researcher Ian Wong said: “It’s not like multiplication, where 2 x 3 is the same as 3 x 2. The material has a ‘memory’ and we get different results when we wrinkle or crumple in a different order.”
The team showed the approach could enhance the electrochemical behaviour of graphene, claiming crumpled graphene used as a battery electrode had as much as a 400% increase in electrochemical current density compared to flat graphene sheets. That increase, said the team, could make for more efficient batteries.
“You don’t need a new material to do it,” said Dr Po-Yen Chen. “You just need to crumple the graphene.”
A further application for crumpled graphene could be in stretchable electronics, including wearable sensors.
The group plans to continue experimenting with different ways of generating structures on graphene and other nanomaterials. “There are many new 2D nanomaterials that have interesting properties, not just graphene,” said Wong. “So other materials or combinations of materials may also organise into interesting structures with unexpected functionalities.”
