Rolled-up Nanotechnology: Materials Issue and Geometry Capability

Rolled-up nanotechnology is an appealing technique that tunes planar films into complex 3D fine structures. The rolling-up mechanism and methodology of a huge variety of materials and their combinations are summarized, including metals, insulators, traditional semiconductor families, polymers, and recently emerged 2D materials. The basic principles of strain induction, fabrication methods, and technical aspects of rolled-up nanotechnology are described. The control over the geometry, as well as its deformation, directionality, and chirality are also discussed. Apart from rolling up into tubes or rings, springs, and other 3D complex structures can also be fabricated through this technique. Exploiting novel physical and mechanical properties in these rolled-up structures has recently inspired numerous applications, including optical resonators, energy storage, drug delivery, gas detection, and environmental decontamination. Such widely applicable and highly tunable 3D architectures open up exciting future opportunities for on-chip applications.