Defect Healing in Graphene via Rapid Thermal Annealing with Polymeric "Nanobandage"

It is crucial to establish a high-throughput healing method of defects in graphene for post-silicon device fabrication, as defect introduction during synthesis and characterization processes is unavoidable. Current healing methods, such as conventional thermal annealing, are either time-consuming, highly specialized, or tedious. To this end, we have developed a new time- and energy-efficient healing approach for graphene, utilizing polymer-assisted rapid thermal annealing (RTA). In this method, a nitrogen-rich, polymeric “nanobandage” is coated directly onto graphene and processed via RTA at 800 ^oC for 15 seconds. In this process, the polymer matrix is designed to be cleanly degraded, while nitrogen released from the nanobandage diffuses into graphene, forming nitrogen-doped healed graphene. X-ray photoelectron spectroscopy (XPS) confirms that 1~3 atomic % nitrogen relative to carbon was successfully doped into the graphene, an amount comparable to other conventional methods. Furthermore, electrical transport measurements indicate that the nanobandage treatment recovers the conductivity of electron beam-treated defective graphene at ~85 %. The nanobandage approach shows great promise for use with other 2D materials with a variety of dopants by simply changing the polymer formulations.