Graphene-based origami with bidirectional bending and folding

Abstract

The precise fabrication and deformation of three-dimensional (3D) microstructures, such as origami and kirigami with folded features typically ranging from a few to several tens of micrometers, have gained significant interest owing to their versatility in advanced microfabrication processes. However, conventional approaches relying on flexible polymers or thin metals face limitations, such as unidirectional bending and poor spatial resolution in localized deformation. Here, we present a strategy to construct graphene-based origami structures by harnessing the mechanical properties of graphene and exploiting electron beam (e-beam)–induced deformation of graphene-polymer double layer. Poly(methyl methacrylate) (PMMA)/graphene bilayer films exhibit a significant shift in the neutral axis due to the high in-plane stiffness of graphene, enabling controlled bidirectional bending under selective e-beam irradiation. By sequential e-beam exposure on PMMA-based structures with spatially patterned graphene, we achieve complex 3D geometries, including flower- and crown-like motifs, as well as folding mechanisms such as chair-like pop-up designs and box-shaped enclosures. Furthermore, we demonstrate rotational motion in wheel-shaped structures, translating out-of-plane bending into in-plane rotation by the shortening effect. Our approach expands the design freedom and functional capabilities of microfabricated systems, offering a powerful platform for programmable, reconfigurable 3D architectures in microelectromechanical systems (MEMS), robotics, and soft materials.