Utilising Curcumin, Turmeric Extract and Cinnamon Extract Solutions for Graphite Liquid Phase Exfoliation

This work aimed at utilizing extracts from inexpensive plants including turmeric and cinnamon to exfoliate graphite compared with the expensive curcumin which was commercially derived from turmeric. The extract solutions were prepared from 5 g of powder immersed in 100 mL ethanol, which yielded the extract concentration of 10.4 and 16.8 mg/mL for turmeric and cinnamon, respectively, whereas curcumin solution at 0.5 mg/mL ethanol was used. The loading of graphite was fixed at 25 mg/mL. The mixture was sonicated at 50oC for 2 h at 200 W and 40 kHz, followed by settling at room temperature for 2 h. Finally, the exfoliated graphite was collected by centrifugation of the supernatant at 10500 rpm for 30 min. The yields obtained from using curcumin, turmeric extract and cinnamon extract were 0.28±0.07%, 0.32±0.096% and 0.36±0.126%, respectively, comparable to those previously reported for liquid phase exfoliation. However, Raman spectroscopy results considering I2D/IG and FWHM of 2D peak showed that the quality of the sample using curcumin was the highest and comparable to the commercial graphene-based product, followed by turmeric and cinnamon. SEM micrographs did not show significant differences among all samples. A TEM figure showed that the exfoliated product was multi-layer graphene-based material.