Nitrogen-doped graphene used to create highly sensitive sensor

An international team of researchers working at Penn State University have developed a highly sensitive chemical sensor using nitrogen-doped graphene as a substrate. This technique can detect trace amounts of molecules in a solution at very low concentrations.

A model showing the charge transfer (e-) mechanism of Rhodamine B molecules (top) interacting with N-doped graphene (bottom sheet) when excited with different laser lines, which leads to ultrasensitive molecular sensor with N doped graphene.

Raman spectroscopy was used for the development of this sensor, which is a common identification technique used to detect the unique internal vibrations of various molecules: when a laser light irradiates crystals or molecules, it scatters and shifts colors. That scattered light can be detected in the form of a Raman spectrum, which serves as somewhat of a unique fingerprint for every Raman-active irradiated system. Different colors in the visible spectrum will be associated to different energies.