Polycyclic Molecule Chemical Vapor Deposition of Amorphous Monolayer Carbon

Abstract Amorphous monolayer carbon (AMC), a new type of carbon nanomaterials created by merging modulations of the crystallinity and dimension, is of particular research interest since it has shown unprecedented properties that its crystalline counterpart–graphene–does not possess. The conductivity of AMC is controlled by its degree of disorder and can be continuously tuned with nine orders of magnitude. As one emergent carbon nanomaterial, the fundamental properties of AMC and its potential in applications remain largely unexplored. However, its current synthesis relies on one specific, lab‐synthesized molecule, hampering further extensive investigations. Here, the feasible synthesis of AMC is reported by chemical vapor deposition using commercial polycyclic molecules, which prove to be effective in repeatably obtaining AMC with a controllable degree of disorder and large sizes. By the backward‐compatible regrowth, the in‐plane, crystalline‐amorphous heterostructures are demonstrated in one monolayer of carbon with mechanical continuity across the homojunction. Conductance measurements confirm in such monolayers the precise controls over both the spatial location and electrical properties, which are not only conductive or insulating but continuously tuned. These results represent a significant step toward understanding the mechanism of AMC growth and pave the way for electronic devices using 2D amorphous materials.