Photo-reduction was used to reduce the oxygen content in Graphene Oxide and correlated to Young’s modulus measurements*

Finding a cost-effective way to make graphene would be beneficial to our world. Mechanical properties of graphene oxide were studied using and AFM system. Specifically, Young's modulus, stiffness, and hardness of graphene oxide samples were measured as a function of sample thickness. Results obtained for Young’s modulus ranged from 24 GPa to 277 GPa for samples of thicknesses 1.4 µm to 93 nm. Once the Young’s modulus values were obtained, photo-reduction was used to reduce oxygen content in graphene oxide samples using a 405 nm ultraviolet laser for 36 hours. Young’s modulus was reevaluated after photo reduction and its value increased from 24GPa to 44GPa for the 1.4 µm thick sample.