Plasma-based fabrication of graphene: US patent granted
Graphene, one-atom thick crystal of carbon, is a new cutting-edge material gathering a set of unique physicochemical properties, ranging from its extreme mechanical behaviour to its exceptional electrical and thermal conductivities. However, large-scale applications of graphene have not yet taken off because of the very low quality of the commercially available graphene and derivatives.
A team of researchers (Elena Tatarova, Júlio Henriques, Luís Lemos Alves and Bruno Gonçalves) of the Plasma Engineering Laboratory of group N-PRiME with Instituto de Plasmas e Fusão Nuclear developed a process to fabricate free-standing graphene using plasma technology, at much lower production cost than the other existing market solutions. They were granted by the US Patent Office the first international patent on the “Process, reactor and system for fabrication of free-standing two-dimensional nanostructures using plasma technology” (ref US 11254575B2).
The versatile plasma-based single-step process allows the continuous large-scale conversion of cheap carbon-based precursors (such as bioethanol and greenhouse gases) into high-value, high-quality graphene and derivatives (e.g., N-doped graphene) with tailored properties and high-yield (40 mg/min), at ambient conditions. The stream of a precursor and an inert gas is subjected to an intense microwave plasma that decomposes the precursor into its atomic and molecular constituents. The temperature and the flow of the constituents are then carefully controlled, via the combined action of a cooling device and the exposure to infrared radiation, within the discharge tube featuring a tailored geometry. The nucleation of the precursor constituents occurs downstream, resulting in the production of floating nanostructures with the prescribed morphological, structural and functional properties.
The patent is an outcome of project PEGASUS (Plasma Enabled and Graphene Allowed Synthesis of Unique nanoStructures) that embodies the plasma-driven controllable design of matter at the atomic scale level to develop a disruptive technology and a proof-of-concept machine for the manufacturing of consistent high-quality batches graphene and derivatives at a large-scale (3 other national patents granted).
The invention targets graphene users and consumers developing new products and devices, for applications as varied as energy storage and conversion devices (e.g. electrodes for supercapacitors, AC filtering lines), materials for hydrogen streams purification & storage, composite materials, jet inks, metamaterials, and negative dielectric permittivity materials.
The team is working hard to find investors to bring this invention to the market.
