The specialists of the Rusgraphene company and the Laboratory of Spectroscopy of Nanomaterials of the GPI RAS developed an energy-saving method for the synthesis of high-quality CVD graphene without the use of explosive gases. The results are published in the journal Physica Status Solidi.
A commercially promising technology for the synthesis of large-size and high-quality graphene films is the CVD method, a method of chemical gas-phase deposition of carbon on the surface of metal foils. Available on the market installations use tube furnaces in which metal substrates are placed and hydrocarbon gas methane (CH4) or acetylene (C2H2) is supplied. At a high temperature near (1050 ° C) the gas decomposes into hydrogen and carbon, the latter is deposited on the surface of the substrate, forming a monolayer graphene film.
A significant drawback of this technology is the need to work with flammable and explosive gases - methane, acetylene and hydrogen gas. Strict safety requirements significantly reduce the scope of applications using standard CVD methods. Employees of Rusgrafen company together with colleagues from the Laboratory of Nanomaterial Spectroscopy of the IOF RAS solved this problem and developed an absolutely safe technology for the synthesis of graphene films.
The elimination of explosive gases has become possible through the use of inexpensive and safe sources of carbon - polymers such as polymethyl methacrylate (plexiglass) and paraffin. The tube furnace has been replaced by a vacuum chamber. The polymer is applied to a metal substrate, which is then heated by the resistive method to the temperature necessary for the synthesis of graphene. Energy is not spent on heating the internal space of the chamber, which allows one to reduce the power consumption of the installation by an order of magnitude compared to existing analogues. The heating and cooling rate of the metal substrate is regulated by special software from 1 degree per minute to 500 degrees per second. The quality of the synthesized graphene films is not inferior to the best samples obtained using the classical CVD method.
This technology is implemented in a compact, safe and energy-efficient installation for the synthesis of graphene Graphene Submarine 2.0 - the initial version, which is produced and implemented by Rusgrafen primarily for educational institutions, universities and schools.
Controlled Graphene Synthesis from Solid Carbon Sources original paper