Researchers with Johns Hopkins University and MIT have shown a way to cause flat sheets of graphene to self-fold into 3D geometric shapes. The group explains how they prepared the sheets and then used heat to cause them to fold. The ability to create 3D objects from sheets of graphene can advance opportunities in fields like sensors, wearables and more.
In their work, the researchers developed a micro-patterning technique that leads to the flat graphene sheets bending along predesignated lines when heat is applied, causing the sheet to form into shapes. The new method not only preserves the intrinsic properties of the graphene, but it was also found that the creases can cause a band gap in the graphene, which can be extremely useful.
The team explained that the technique is also compatible with traditional lithography and can be applied at the wafer scale. Also, it is highly parallel, which means it should not present manufacturing problems. The scientists also report that they tested their technique by creating 3D shapes that were used to hold living cells and nonlinear resistors. They also used one in the creation of a transistor device. By creating such useful 3D structures, the team believes they have shown that their technique could be used to build viable wearable electronic devices and sensors that could be used inside of a living organism.
In November 2015, scientists at Donghua University in China demonstrated a way to cause tiny (0.8 to 6 centimeter) graphene oxide-based objects to move in specific ways using heat and infrared light. The work was inspired by origami, an art form based on folding paper.