This study introduces a novel, sustainable, and eco-friendly 2-step microwave-assisted synthesis of coconut shell waste-derived GO. Notably, this is the first report of GO synthesis from coconut waste utilizing the Titan MPS microwave system. In the first step, three samples were carbonized at 200 °C for 1 hour using microwave heating. The first sample consisted of 100 g of coconut shell powder mixed with 60 ml of distilled water (DW), the second involved 5 g of coconut powder combined with 8 ml of nitric acid (HNO 3 ), 1 ml of hydrochloric acid (HCl), and 1 ml of hydrofluoric acid (HF), while the third sample used 5 g of coconut powder with 6 ml of HNO 3 , 0.5 ml of HCl, and 0.5 ml of HF. In the second step, all samples were oxidized using 6 g of potassium permanganate (KMnO 4 ) and then stabilized with 15 mL of hydrogen peroxide (H 2 O 2 ). The successful synthesis of GO was characterized through various techniques, including Thermogravimetric Analysis (TGA), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FESEM), and Energy Dispersive X-ray (EDX) analysis. The microwave-assisted method significantly improved the GO yield up to 79%, compared to approximately 20% using conventional methods. Furthermore, TiO 2 /GO, ZnO/GO, and ZrO 2 /GO nanocomposites were fabricated using various ratios for photocatalytic degradation. Among all, ZnO/GO (80:20) nanocomposite showed the highest efficiency under visible light irradiation. The results underscore the potential of coconut waste-derived GO nanocomposites as sustainable and efficient photocatalysts for wastewater treatment & other industrial applications. • 2-step Microwave-assisted coconut shell-derived graphene oxide was prepared. • The comparison of conventional hummer’s & other selected methods was done to evaluate the GO yield & other parameters. • TiO 2 /GO, ZnO/GO, and ZrO 2 /GO nanocomposites were successfully fabricated using different ratios. • GO samples were characterized using TGA, XRD, FTIR, FESEM, and EDX to confirm their structural, chemical, and morphological properties. • Nanocomposites were further evaluated for their photocatalytic performance. The results showed selected samples with the highest efficiency, demonstrating the potential of these eco-friendly materials for effective and sustainable environmental remediation.
Balqis et al. (Sun,) studied this question.