Growth of High‐Quality Graphene from Solid Polycyclic Aromatic Hydrocarbons Using a Sealed Crucible Method

Abstract The chemical vapor deposition (CVD) of graphene using solid polycyclic aromatic hydrocarbons (PAHs) as carbon sources has emerged as a promising technique for synthesizing high‐quality graphene. However, the use of solid PAHs often results in defective graphene, and the underlying growth mechanism remains poorly understood. In this study, the formation of graphene from pyrene, the simplest solid PAH, on Cu foil inside a sealed crucible, is investigated. Initially, pyrene films are converted into amorphous carbon (a‐C). This is followed by the gradual crystallization of a‐C near the Cu surface into graphene. The sealed crucible confines the carbon sources, preventing the complete etching of graphene and enabling an extended crystallization period. Furthermore, it is demonstrated that reducing the crucible volume extends the crystallization time, resulting in the formation of highly crystalline graphene. Thus, high‐quality graphene from pyrene with electron mobility comparable to that produced using CH₄‐based CVD is successfully synthesized. These findings demonstrate the potential of solid carbon sources as viable alternatives to CH₄ in graphene synthesis.