Syntheses of reduced graphene oxide using aqueous extract of Syzygium cumini as green reducing agent

Full text: Graphene-family nanomaterials have interesting properties, that have grabbed appreciable attention on the path of researches seeking new materials for future applications. Despite the great potential, the high price of these materials is a barrier their application. Syntheses that use chemical routes provides a high quality reduced graphene oxide (RGO). However, the reducing agents used are harmful to the environment [1]. Green reducing agents (GRA) have been proposed with the aim of reducing costs, as well as rejects produced. In this way, the Syzygium cumini (Jambolão) appears with a potential GRA, because it has a rich composition in phenolic compounds (especially tannins) [2]. Therefore, the present work has as objective the obtention of RGO by chemical reduction using the aqueous extract of Jambolão. The modified Hummers method was used to obtain graphene oxide (GO) [1]. The aqueous extract was obtained using dry leaves in the proportion of 1:10 w/v at 60°C [3]. The GO was added into the extract solution and stirred at 90 °C for 8h. The resulting materials were oven dried at 60°C and characterized by X-ray diffraction (DRX) and Fourier-transform infrared spectroscopy (FT-IR). XRD results from GO showed diffraction pattern at 11°, characteristic of this material. In the diffractogram of RGO has observed patterns at 15.21° and 28.31°, demonstrating the structural modification of the RGO. FT-IR spectra of both materials presented bands at 4000, 3400, 2400, 1732, 1448, 1370, and 1227 cm-1, that were attributed to C-OH, CH, COOH, C=C, OH, and CO, respectively [3]. It is possible to conclude that the extract of Jambolão has great potential for green production of RGO. References: [1] I. M. Jauris et al., Phys. Chem. Chem. Phys., vol. 18, pp. 1526–1536, 2016. [2] K. K. H. De Silva et al., Carbon N. Y., vol. 119, pp. 190–199, 2017. [3] D. Hou et al., Mater. Chem. Phys., vol. 183, pp. 76–82, 2016. (author)