Progress and challenges on 3D tubular structures and devices of 2D materials

Due to their unique structures and properties, emerging two-dimensional (2D) materials have been at the frontier of research in, e.g., materials science, physics, and engineering. Three-dimensional (3D) tubular geometry enables 2D materials unparalleled advantages for various applications, for example, wide-angle infrared photodetectors, extremely sensitive molecular sensors, and memory with high density. Furthermore, 3D tubular structures offer a promising integration platform into chips with a broad range of materials, especially 2D materials. In this Perspective, we highlight state-of-the-art methods to assemble/manufacture 2D materials into 3D tubular structures/devices via self-rolled-up or template methods. These tubular 3D devices inspire unique physical, chemical, and mechanical properties for optical microcavity, photodetector, on-chip electronics, and bubble-propelled microengines. On-chip manufacture of 3D tubular structures/devices provides great opportunity and challenge for 2D materials for More than Moore applications such as unconventional electronics, smart sensors, and miniaturized robots.