T-graphene could be used to fabricate superconducting nanodevices in the future according to new research findings from Nanjing University.
“A single-layer planar carbon sheet with four- and eight-membered rings, known as T-graphene, could be an intrinsic elemental 2D superconductor with a superconducting transition temperature (Tc) of more than 20 K.
This is the new finding from researchers at Nanjing University in China who say that single-layer T-graphene, which could be used to fabricate superconducting nanodevices in the future, might be peeled off from a precursor potassium T-graphene intercalation compound (C4K) and be synthesized under high pressure in the laboratory. The precursor itself could have record values of Tc for layered carbon-based superconductors.
There are single-layer materials, such as iron selenide (FeSe), molybdenum disulphide (MoS2) and niobium selenide (NbSe2) that can be superconductors but some of these need to be doped or strained to exhibit superconductivity. Graphene (a sheet of carbon atoms just one atom thick) is another example.
Indeed, researchers recently reported superconductivity in “magic-angle” bilayer graphene, a result that caused quite a stir, but the magic angle can be quite tricky to control in experiments.
The list does not end there: many carbon-allotrope related materials, such as graphene intercalation compounds (GICs), fullerene alkali metal compounds, nanotubes, boron-doped diamond and boron carbide, are also superconducting.
GICs, in which metallic atoms intercalate between graphene sheets, are particularly interesting to study, says study team leader Jian Sun who is at the School of Physics and the National Laboratory of Solid State Microstructures at Nanjing University.”
“Once the single-layer T-graphene is made, it could be stacked with other 2D materials such as graphene or transition metal dichalcogenides (using standard layer-by-layer or so-called vertical techniques) to fabricate superconducting devices,” he says. “What is more, the high-pressure synthesis method we have put forward in this work could be a new strategy to obtain single-layer materials that cannot be easily synthesized at ambient conditions. This provides a road map to obtaining such promising materials and opens a new door in the field.”
Source: Physics World by Belle Dumé
Image: Synthesis routes for T-graphene. Credit: Chinese Physics Letters, courtesy: S Jian