posted on 2019-08-23, 15:33authored byMichael
F. Reynolds, Kathryn L. McGill, Maritha A. Wang, Hui Gao, Fauzia Mujid, Kibum Kang, Jiwoong Park, Marc Z. Miskin, Itai Cohen, Paul L. McEuen
Small-scale optical
and mechanical components and machines require
control over three-dimensional structure at the microscale. Inspired
by the analogy between paper and two-dimensional materials, origami-style
folding of atomically thin materials offers a promising approach for
making microscale structures from the thinnest possible sheets. In
this Letter, we show that a monolayer of molybdenum disulfide (MoS2) can be folded into three-dimensional shapes by a technique
called capillary origami, in which the surface tension of a droplet
drives the folding of a thin sheet. We define shape nets by patterning
rigid metal panels connected by MoS2 hinges, allowing us
to fold micron-scale polyhedrons. Finally, we demonstrate that these
shapes can be folded in parallel without the use of micropipettes
or microfluidics by means of a microemulsion of droplets that dissolves
into the bulk solution to drive folding. These results demonstrate
controllable folding of the thinnest possible materials using capillary
origami and indicate a route forward for design and parallel fabrication
of more complex three-dimensional micron-scale structures and machines.