About the Journal :
Graphene is a flat layer of carbon atom, and is a layer of graphite with a thickness of a few tenths of a nanometer that due to its porous structure and high ionic transfer rate, it has been considered in electronic applications, such as cloud storage capacitors with high energy. In this research work, laser scribed technique has been regarded to synthesize grapheme on the surface of a DVD and manufacture graphene and graphene composite super capacitors with Molybdenum disulfide. For this purpose, first, by Hummers method, graphite was converted to graphene oxide (GO) in an acidic environment containing Sodium nitrate, Potassium permanganate and sulfuric acid. Centrifuges and ultrasonic devices were utilized for the homogenization of graphene oxide solution. GO homogeneous solution was applied on the surface of specific DVDs and the set was dried at room temperature. For GO reduction and transform it into graphene, a suitable laser, with programming of super capacitor particular pattern was used. By applying energy with the amount of resonance frequency of graphene and oxygen bond, the laser broke the connection and the reduction action and reaching to graphene was done. Thus, the optimal wavelength of laser was determined to reduce the GO. In this study, the process of graphene synthesis and applying the super capacitor specific pattern were carried out in single step that is the biggest advantage of laser scribed graphene (LSG) method. In present study, TEM was utilized to examine the layered structure of GO, SEM was used for microstructural studies the XPS was used to investigate elements present in the layer applied on DVD, and the Raman spectroscopy was applied to investigate the quality of prepared graphene through studying G and D peaks., two tests of cyclic voltammetry (CV) and Galvano static charge/discharge (CC) were applied to study the performance and power of energy storage in super capacitors, Finally the long-term charge-discharge stability of the LSG was plotted which indicates that specific capacitance has decreased very slightly from its primary capacitance of ~ 10 F cm-3 and its cyclic stability is favorable over 1000 cycles.
Keywords: Graphene; Laser Scribed; Lithography; Synthesis; Hummers method..