Carbon materials have a fantastic behavior as electrode surfaces because they are cost-effective, chemically inert, have a low background current and a wide potential window. Although the carbon era seemed to come to an end, the development of new carbon nanomaterials has provided novel applications for carbon in the 21^st century. Physical and chemical properties of these materials depend mainly on their structure, so their characterization is essential to choose the right material for the appropriate applications.

Raman spectroscopy is a very attractive technique for material characterization and allows to know in an effortless way some information about the structure of carbon materials in terms of the sp² and sp³ bonds, and, therefore, about their possible properties. In general, the G band of the Raman spectra (around 1580 cm^-1) could provide information on the fraction of sp² bonds and the D band (around 1300 cm^-1) could provide information on the fraction of sp³ bonds (and some disorder in the structure). In some cases, a G’ band also appears around 2600 cm^-1 that could provide some knowledge on the layered structure of some of these materials.

DropSens screen-printed electrodes (SPEs) are low-cost, disposable devices, which are available with working electrodes fabricated in several carbon materials. Their properties can be studied by Raman spectroscopy as described in this Application Note.