Abstract:
Chemical vapour deposition (CVD) of cooking palm oil precursors with a nickel (Ni) catalyst is an established method to produce graphene-based materials. Nonetheless, transferring the graphene sheets from the substrate surface to a selected target substrate presents a major challenge. The utilisation of well-known poly (methyl methacrylate) (PMMA)-assisted graphene transfer promotes defects, impurities, folds, and wrinkles in the graphene sheets, thus affecting its properties. Consequently, the present study demonstrated a polymer-free graphene sheets transfer technique on a Ni substrate derived from cooking palm oil. A dropwise hexane layer substituted the PMMA supporting layer during the etching process to remove the Ni substrate. The quality of the graphene sheet was investigated with optical microscopy by employing a Leica DM1750 M microscope, scanning electron microscopy (SEM) with a Hitachi S-3400N, and Raman spectroscopy utilising a UniDRON automated microscope Raman mapping system with 514 nm laser excitation. Resultantly, macroscopically clean and crack-free graphene sheets were was obtained. Furthermore, the technique was less complicated than the PMMA-assisted transfer technique. The Raman spectra of the polymer-free method also revealed visible graphene peaks, which was absent in the PMMA-transferred samples. © 2022, Malaysian Society of Analytical Sciences.
