On graphene - to the stars: the material from graphene oxide moves under the influence of light

Graphene sponge

A new unexpected property of graphene was discovered by Chinese scientists from Nankai University. Experimenting with a “graphene sponge” obtained from graphene oxide, they found that the laser beam could give a sponge a perceptible acceleration.

Scientists have received a graphene sponge from crumpled graphene oxide sheets. They tried to cut this material with a laser cutter, and suddenly found that under the influence of a laser beam, the material began to move. Being placed in a vacuum chamber, small pieces of a graphene sponge turned out to be thrown up by a laser up to a height of 40 cm. They were even forced to move by the sun's rays, focused with a conventional lens.
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It is not yet completely clear how the laser (and the light in general) shifts something noticeably larger than individual atoms. It is possible that the effect of the solar sail takes place, when photons impart acceleration to the sail, giving it its impulse. More recently , LightSail , the first commercial satellite operating on this principle, was launched .

The second idea that the experimenters came up with was that under the influence of a laser, carbon atoms knocked out of graphene, which give the sponge a reactive movement - but this idea, by some reflection, was discarded.

According to another hypothesis, graphene absorbs light energy and accumulates because of this charge of electrons. When the accumulated charge exceeds the capacity of the material, the "extra" electrons are "fired" outside and give a sponge a boost. This hypothesis was partially confirmed when the experimenters recorded the current emanating from a piece of sponge. It is not clear why electrons do not fly away in random directions, but fly in an organized way in one direction.

If it turns out that, on the basis of this phenomenon, it is possible to construct, for example, an engine for spacecraft, then in the case of space flight, a breakthrough may await us. This will actually mean the creation of a ship that can move without fuel, while the efficiency of a propulsor on graphene, according to preliminary calculations, is several orders of magnitude higher than the efficiency of solar sails.