SCIENTIFIC EDUCATIONAL CENTER science idea

A unique method for the synthesis of multigraphene films at room temperature was created by the NUST MISIS research team. This will allow applying multigraphen to the surface of low-melting metal powders to create qualitatively new 3D composites. The work is published in the journal Materials Chemistry and Physics.

Graphene additives in materials used in 3D printing improve the mechanical and functional properties of composite products: their thermal conductivity, mechanical strength, and electrical conductivity increase. This is an urgent task when creating complex parts for the aerospace industry using 3D printing methods.

The simplest method of graphene synthesis is the micromechanical stratification of graphite, proposed by the 2011 Nobel Prize laureates Geim and Novoselov, however, it is inefficient and is used mainly for laboratory research.

One of the ways to obtain graphene by electrochemical method is its formation from molten salts. However, the synthesis of graphene in this case is carried out at a temperature of 500-700 ° C, which eliminates the possibility of its deposition on particles of low-melting metals, such as aluminum, and therefore significantly narrows the range of possible composites modified with graphene.

Scientists of the laboratory "Catalysis and Processing of Hydrocarbons" of NUST MISIS solved this problem by developing a new low-temperature technology for producing multigraphen for application to silumin (an alloy based on aluminum and silicon) powders used in the creation of composites by 3D printing.

"Our goal was to produce a significant amount of graphene-and silumin-based powder composite for 3D printing. To do this, we performed electrochemical deposition of graphene from a weak solution of sulfuric acid with the addition of sucrose. When graphene was deposited on silumin powder, the solution temperature did not exceed 25-30oC. The resulting composites were then fused using the SLM method to produce 3D products, " said Sergey Eremin, co-author of the study, engineer of the Department of Functional Nanosystems at NUST MISIS.

According to the developers, the proposed technology allows you to adjust the thickness of the deposited graphene layer and maintain its uniform distribution in the powder.

In the future, the development team plans to improve the technology of multigraphene synthesis by controlling the thickness of the resulting graphene layers, as well as learn how to produce continuous graphene films.

The second direction of technology development is the direct production of graphene powder with a high specific surface area, which will improve the sorption properties for creating filter materials.

If such powders are modified with silver or copper nanoparticles, a bactericidal effect is added to the high filtering properties. Filters based on them can be used to purify water and air in industrial and domestic conditions.

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