Tech overview:

The presented technology uses low-temperature atmospheric pressure electric plasma to start the fast plasma-initiated reduction-exfoliation of materials based on graphene oxide to so-called reduced graphene oxide (rGO), with properties partially similar to pristine graphene. The technology is based on the use of an innovative and industrially proven source of low-temperature electric plasma, the so-called Diffuse Coplanar Surface Barrier Discharge (DCSBD).

This technology uses specially prepared graphene oxide, which is subsequently exposed to the effect of low-temperature atmospheric plasma. A special form of GO and an optimized plasma source using the thermodynamic properties of the reduction reaction of GO to rGO allow us to prepare plasma-reduced GO extremely quickly (~1s) and efficiently. The results demonstrate an improvement in the electrical properties of rGO by 6 orders of magnitude.

Benefits:

• The technology works at atmospheric pressure, uses technical grade nitrogen as the working gas, and starts at laboratory temperature. The maximum temperatures reached during plasma-initiated reduction–exfoliation reach approx. 250 °C (and that only in the order of tenths of a second). For comparison, classical methods of reduction of GO to rGO work at a temperature of more than 1000 °C in inert and reducing gases.
• The technology is based on the use of DCSBD plasma technology. It is a commercially available, proven, and industry-tested technology. Therefore, this is not a prototype laboratory device or a concept that needs to be tested.
• The entire technology is very robust in the sense of the absence of any extremely sensitive and expensive components and complicated instrumentation.
• The technology is designed from the beginning to be compatible with roll-to-roll / in-line production. The entire process enables relatively easy scalability up to an industrial scale to produce rGO materials of large dimensions with a large production capacity.
• Plasma reduction-exfoliation of GO is a very fast process lasting a few seconds at most. In comparison, classical thermal and chemical reduction of GO is a lengthy process lasting hours to tens of hours.
• The use of a non-isothermal plasma process provides the possibility of a simple modification of rGO during the process itself and thus the production of materials with specific properties. By using a specific atmosphere during plasma reduction, it is possible to realize, for example, rGO doping (nitrogenization, fluorination). It is possible to supplement the material with, for example, nanoparticles and thereby produce various composites, or realize the simultaneous reduction of nanoparticles of oxides of various metals.
• To the above advantages, it is a very energy-efficient production with low energy consumption and the absence of extremely expensive and complicated technologies reduces initial investments and lowers operating costs.

Applications:

Commercial use finds graphene materials in additive manufacturing, that are possible to implement graphene of different compositions, forms, and properties into already used production processes to improve the mechanical, electrical, thermal, or catalytic properties of already available products. We are currently focusing on the production and optimization of the properties of thin paper with a thickness of less than 10 µm, made from plasma-reduced graphene oxide, which would be applicable in the energy industry as, for example, a replacement for the rigid conductive substrate in solar panels, or as a replacement for graphite in lithium batteries to improve the charging capacity and charging speed. We are currently working on optimization of the production of plasma-reduced graphene oxide paper to verify it as electrodes in CR2032 flat button batteries.

Another potential use of thin paper from reduced graphene oxide is to improve the mechanical properties of composite materials such as laminated composites. Another example of the use of reduced graphene oxide in the form of paper with the addition of selected elements from the periodic table is its use as a catalyst for the chemical industry, especially the production of ammonia using the Haber-Bosch method or the production of methane from carbon dioxide using the Sabatier reaction. At the same time, our technology makes it possible to prepare plasma-reduced graphene oxide in the form of powder or highly porous aerogel, which can be applied in many other branches of industry.

Commercial opportunity (seeking):

• partner for technology licensing and its application in practice
• an investment partner for the further development of technology and the eventual establishment of a spin-off company

IP protection status:

International application filed, CZ patent in force