Towards large-scale in free-standing graphene and N-graphene sheets

Microwave-driven plasmas were successfully applied for the first time to the selective synthesis of high-quality graphene and N-graphene free-standing sheets at high-yield. The main advantages of the plasma approach are the scalability and the control over the assembly process.

Moreover, this key enabling technology is non-destructive, free of toxic chemicals, metal catalysts and substrates, and allows the use of carbon precursors in solid, liquid or gas state at atmospheric pressure. Wave-driven plasmas provide a rapid, single-step, cost-efficient and environmentally-friendly alternative to chemical methods in the controllable manufacturing of graphene/N-graphene.

The selective synthesis is achieved via a synergistic tailoring of the high energy-density plasma environment and the “cold” outlet gas flow, where in situ infrared and ultraviolet radiation are applied. As outcome, it is possible to control the position and the amount of energy and matter delivered from the plasma bulk to the building units of C2 radicals, and of C and N atoms that develop into nanostructures.

The end-result is a high-quality product, obtained in a reproducible manner with the desired morphological, structural and functional properties: graphene free-standing sheets, collected using a Hurricane Cyclone system, ~40% in the form of single atomic layers, with low-content of oxygen and high-ratio of sp2/sp3 carbons (~15).

The article 'Towards large-scale in free-standinggraphene and N-graphenesheets' by E. Tatarova and collaborators [1], addressing the large-scale fabrication of graphene and its derivatives, was published in Scientific Reports. The work pertains to the recently emerging cutting-edge field of Plasma Nanoscience. 

The research, lead by IPFN, was performed in the framework of a strong collaboration effort, involving Instituto Superior Técnico / University of Lisbon and Faculdade de Ciências e Tecnologia / New University of Lisbon (Portugal), GREMI (France), Faculty of Physics / Sofia University (Bulgaria), Institute Josef Stefan Ljubljana (Slovenia), and Kiel University (Germany). A patent describing the process, the reactor and the system of fabrication is currently pending [2].

  1. E. Tatarova, A. Dias, J. Henriques, M. Abrashev, N. Bundaleska, E. Kovacevic, N. Bundaleski, U. Cvelbar, E. Valcheva, B. Arnaudov, A. M. Botelho do Rego, A. M. Ferraria, J. Berndt, E. Felizardo, O. M. N. D. Teodoro, Th. Strunskus, L. L. Alves & B. Gonçalves, 'Towards large-scale in free-standing graphene and N-graphene sheets', Scientific Reports 7, Article number: 10175 (2017) 
  2. E. Tatarova, J. Henriques, L.L. Alves, B. Gonçalves, 'Process, reactor and system for fabrication of freestanding two-dimensional nanostructures using plasma technology', WO 2017196198 A2 (2017)