Optical temperature determination during laser annealing of graphite oxide

Highly conductive, graphene-like, reduced graphite oxide (rGO) can be synthesized from graphite oxide (GO) via photochemical methods, solution chemistry, and high-temperature treatments. In order to develop intricate circuitry and conductive patterns out of rGO, controlled laser-based annealing of GO has been extensively developed. Here, we show that this laser-based technique creates a localized, optically induced thermal reaction in GO. We determine the local temperature at the irradiation spot by comparing the Stokes and anti-Stokes scattering intensities giving us a simultaneous measure of temperature during annealing. Using this technique, we compare the optically induced GO-to-rGO transition with standard induction furnace annealing. The optically created rGO patterns, which we show can be produced in air, argon, and vacuum environments, are characterized using electrical conductivity and Raman scattering. Our ability to generate conductive circuits using optical annealing of GO creates new opportunities for economical carbon-based electronics.