Journal of Physical Science, Vol. 28(3), 19–40, 2017 © Penerbit Universiti Sains Malaysia, 2017. This work is licensed under the terms of the Creative Commons Attribution (CC BY) (http://creativecommons.org/licenses/by/4.0/). Tailoring the Chemical and Structural Properties of Graphene Oxide Nanoplatelets Synthesised at Room Temperature with Diferent Processing Times Guat Yee Toh, 1 Hui Lin Ong, 1* Hong Ngee Lim, 2 Nay Ming Huang, 3 Hazizan Md Akil, 4 Al Rey Villagracia, 5 Gil Nonato C. Santos 5 and Hooi Ling Lee 6 1 School of Materials Engineering, Universiti Malaysia Perlis, Kompleks Pusat Pengajian Jejawi 2, 02600 Arau, Perlis, Malaysia 2 Chemistry Department, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia 3 Low Dimensional Materials Research Centre, Physics Department, University of Malaya, 50603 Kuala Lumpur, Malaysia 4 School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Pulau Pinang, Malaysia 5 Department of Physics, De La Salle University, 2401 Taft Avenue, Manila 0922, Philippines 6 School of Chemical Sciences, Universiti Sains Malaysia, 11800 USM Pulau Pinang, Malaysia * Corresponding author: hlong@unimap.edu.my Published online: 15 November 2017 To cite this article: Toh, G. Y. et al. (2017). Tailoring the chemical and structural properties of graphene oxide nanoplatelets synthesised at room temperature with diferent processing times. J. Phys. Sci., 28(3), 19–40, https://doi.org/10.21315/jps2017.28.3.2 To link to this article: https://doi.org/10.21315/jps2017.28.3.2 ABSTRACT: A simplifed Hummer's method was successfully used in synthesising graphene oxide nanoplatelets. These nanoplatelets were synthesised at room temperature at various processing times (24 h, 72 h, and 120 h). Ultraviolet visible spectroscopy (UV- vis) showed that all synthesised graphene oxide nanoplatelets suspensions have similar broad shoulder absorbance at a wavelength of 300 nm. Furthermore, similar functional groups were detected by Fourier transform infrared spectroscopy (FTIR) across all types of graphene oxide nanoplatelets structures. The efect of processing time on the thickness of the sheet size was interpreted through topology using atomic force microscopy (AFM). The structural properties of graphene oxide nanoplatelets were evaluated using X-ray difraction (XRD). The results showed a slight increase in the interlayer spacing with no sharp distinction in the crystallinity for graphene oxide nanoplatelets at longer processing times. The ratio of carbon to oxygen composition on the surface of each synthesised graphene oxide nanoplatelet was computed using the X-ray photoelectron spectroscopy