10:00 AM - 10:15 AM
▲ [14a-2T-5] Chemical Surface Modification of Graphene Oxide (GO) by Femtosecond Laser Pulse Irradiation
Keywords:Femtosecond laser,Graphene oxide,Aqueous solution
Femtosecond laser pulse irradiation has advantages in graphene oxide (GO) reduction compared to CW and nanosecond lasers because it can reduced thermal effect on targetted materials which can avoid further damage on the graphene basal structure during reduction. In this work series of experiments were conducted in different laser fluences and irradiation time for obtaining optimum reduced graphene oxide (rGO).In this study GO colloidal solution was kept in a glass vial with the volume of 9 mL and used as a precursor. Femtosecond laser pulses (l: 800 nm, pulse width: 100 fs, repetition rate: 300 Hz) were shone vertically to the surface of the solution through a focusing lens with the local length of 35 cm. As a result, 80 mJ/cm2 and 2 hours irradiation were founded as the optimum laser fluence and irradiation time. From UV-vis spectrometer analysis, The absorption peak at 230 nm in the spectrum of the GO solution, which is correlated to the carbon double bond in benzene ring, shifted to 261 nm after 1 hour irradiation and 275 nm after 2 hours irradiation. In addition, Raman spectroscopy of rGO shows that intensity ratio of D and G bands decreased up to 0.81 indicating the enhancement of graphitic region or reduction of defect area. This profiles show that the proposed method can minimize disorder or damage on the graphene basal structure during the reduction.