Researchers have found a way to pack graphene even tighter, taking us a step closer to producing hydrogen and other cleaner fuels.
Graphene has the potential to create a whole range of cleaner, renewable fuels for homes and industry by harnessing the power of the basic elements and the sun.
Now, a team of researchers from Linköping University in Sweden has announced a breakthrough that brings us one step closer to this reality by making it possible to produce graphene with several layers in a tightly controlled process.
The clean-fuel production process involves the extraction of carbon, hydrogen and oxygen from CO2 and water – this can be used to create fuels such as ethanol and methane. Publishing its findings in Carbon and Nano Letters, the research team developed upon its previous work to produce cubic silicon carbide, which consists of silicon and carbon.
By applying graphene to cubic silicon carbide, it is possible to harness the energy of the sun to create these cleaner fuels – however, this isn’t enough for an efficient production process.
“It is relatively easy to grow one layer of graphene on silicon carbide, but it’s a greater challenge to grow large-area uniform graphene that consists of several layers on top of each other,” said Jianwu Sun of the research team. “We have now shown that it is possible to grow uniform graphene that consists of up to four layers in a controlled manner.”
Has ‘extremely promising electrical properties’
One of the biggest difficulties posed by layering multiple layers of the atom-thick material is that the surface becomes uneven as they grow at different rates at various points.
In this case, the edge when one layer ends has the form of a tiny nanoscale staircase, which proves a problem when trying to create large, flat areas. The researchers found a way to get around this staircase issue by growing graphene at a carefully controlled temperature, resulting in a process that makes it possible to control how many layers the graphene will contain.
“We discovered that multilayer graphene has extremely promising electrical properties that enable the material to be used as a superconductor, a material that conducts electrical current with zero electrical resistance,” Sun said. “This special property arises solely when the graphene layers are arranged in a special way relative to each other.”
The multilayered graphene’s superconductive properties have also been confirmed in experiments, making it a possible candidate for a range of technologies such as high-speed trains and nuclear fusion reactors.