Since its isolation by using adhesive tape in 2004 graphene is the new rising star in material science with unique electronic, optical, thermal, chemical as well as mechanical properties (noble prize in 2010). Graphene is known to be the thinnest and at the same time strongest material existing, due to a singular one-atom thick layer consisting of carbon atoms arranged in a two-dimensional honeycomb-like structure. This structure enables e. g. extraordinary electronic and thermal properties and fascinating electron transport phenomena.
Graphene has enormous potential to be beneficially utilized in a range of carbon based molecular electronics since it shows high carrier mobility of up to 200000 cm2/(V·s) at high concentrations and low noise. The corresponding resistivity is less than the one of silver, which provides the lowest resistivity substance known at room temperature. Therefore, graphene has the ideal properties to be an excellent component of integrated circuits and to be used as the channel in a field-effect transistor and in fast switching circuits. In 2011 IBM researchers announced that they created the first graphene-based circuit handling frequencies of up to 10 GHz and a performance unaffected up to 127 °C. Furthermore, numerous reports have emerged where graphene has been utilized as electrode material in super-capacitors or in lithium-ion batteries.
Graphene's high electrical conductivity and high optical transparency (up to 97.7%) makes it an ideal material for optoelectronic applications as in transparent conducting electrodes, required for applications as touch-screens, liquid crystal displays, organic photovoltaic cells, and organic light-emitting diodes. In particular, the mechanical strength and flexibility are advantageous compared to the previously used brittle indium tin oxide (ITO).
Additional characteristics of graphene are a high thermal conductivity (up to 5000 W/(m·K), which is more than in case of diamond), a high nominal surface area as well as enormous breaking strength. Furthermore, detection of a diverse range of analytes including numerous bio-molecules, gases and miscellaneous organic and inorganic compounds is possible since the electrical conductivity of graphene is strongly modulated by adsorbates. For instance, a robust foam structure of few layer graphene with a high specific surface area (850 m2/g) was recently reported with sensitivities of about 20 ppm for NH3 and NO2.
IOLITECNanomaterials offers platelets of graphene with high purity (99.5%) and different thickness (6-15 nm) as well as specific surface area (60-150 m2/g) at reasonable prices. Amounts of up to 50 g are in stock and can be delivered within very short times. Upon request also larger amounts can be provided. In case long term stable and easy-to-handle dispersion are desired, please ask our qualified employees regarding their feasibility.
Text: IOLITEC GmbH, 2013.