Optimization of Graphene Oxide Synthesis Using Hummers Method

Abstract

In the processes of nanomaterial synthesis and characterization, it is important to explore and understand the relationships between variables and levels of processes by introducing experimental design methods and statistical approaches. The main goal of this work is to improve the quality of the graphene oxide (GO) that is made by using the TOPSIS-Based Taguchi Method and the L9(33) experimental design. Various parameters were chosen for experimentation, including samples of graphite with varying levels of purity (85%, 99%, and 99.99%). Prior to initiating the reaction, the graphite underwent pre-application, which involved diverse treatments such as no pre-processing, pre-heating at 200 °C, and ultrasonication. Additionally, different types of auxiliary oxidants (NaNO3, H3PO4, and Na2B4O710H2O) were employed. Raman spectroscopy was used to measure the peak intensity ratio (D/G) of the D peak and the G peak. X-ray diffraction (XRD) was employed to determine the crystal size (CS-nm). The surface area (SA-m2/g) was measured using the BET method. The average particle size (PS-nm) and the Zeta potential (ZP-mv) were determined using a Zeta-Sizer. The atomic ratio of carbon to oxygen (C/O) was also studied using scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM+EDX) to get a better understanding of graphene oxide (GO). The quality criteria's findings were assessed for each experiment using the TOPSIS-Based Taguchi Method, and the optimum circumstances were identified. The recovery rates for D/G, C/O, ZP, SA, PS, and CS were computed as 15.88%, 55.55%, 19.23%, -63.23%, -82.77%, and 20.79%, respectively. The utilization of low-purity graphite and boron compounds in the Hummers method yielded a favorable outcome in the synthesis of graphene oxide. When evaluating the experiment from an economic and environmentally conscious perspective, the results are quite impressive.