Fabrication of Flexible Laser Scribed Grapheme

Graphene conducts electricity and heat better than anything else and hascombination of unique optical and mechanical properties. Electrons havenobilities in graphene over a hundred times those in silicon. Supercapacitors area category of electrochemical energy storage devices that to some extent haveadvantages of both batteries and capacitors. In the present work we used astandard optical LightScribe DVD drive to directly do the laser reduction ofgraphene oxide (GO) films to graphene. GO was prepared by the modifiedHummers‘ method as reported elsewhere. Briefly, a ۲ g graphite powder wasadded to a mixture of ۱ g NaNO۳ and ۴۶ ml H۲SO۴ and the mixture wascooled to ۱۰ °C using an ice bath. In the next step, ۶ g KMnO۴ was graduallyadded to the solution and the reaction temperature was maintained below ۲۰ °C.The mixture was then stirred at ۳۵ °C for ۲ h. The resulting solution wasdiluted by adding ۹۲ ml of deionized water until a dark brown suspension wasobtained. Then, the solution was treated by adding ۳۴۰ ml H۲O۲ solution.Finally, a uniform suspension of GO nanosheets was obtained by adding waterto the resulting precipitate and ۱۲ h of sonicating. The resulting suspensionswere uniformly drop casted on a LightScribe DVD disk and then dried underthe air at an ambient temperature. The GO coated DVD disk was placed in aLightScribe DVD drive with a wavelength of ۷۸۰ nm and a spot size of ۲۰ μm.The reduced composite was peeled off from the DVD disk and was glued to thepolyethylene terephthalate (PET) substrate. The prepared electrodes wereattached to copper wire using silver paste and the exposed areas of silver pasteto electrolyte were passivated. An R۱۲۹۳۴۸ Bruker Equinox ۵۵ Fra ۱۰۶/sspectrometer was used for Raman spectroscopy. The surface of electrodes wasobserved by FESEM (HITACHI S-۴۱۶۰). Cyclic voltammetry (CV) andgalvanostatic charge/discharge (CD) techniques were employed to characterizethe performance of LSG as a promising candidate for electrode materials forsupercapacitors.

Keywords:

Graphene oxide , laser scribed graphene (LSG) , supercapacitors