A novel method of preparing reduced graphene oxide (RGOX) from graphene oxide (GOX) was developed employing vegetable extract, Chenopodium album, as a reducing and stabilizing agent. Chenopodium album is a green leafy vegetable with a low shelf life, fresh leaves of this vegetable are encouraged to be used due to high water content. The previously modified ‘Hummers method’ has been in practice for the preparation of GOX by using precursor graphite powder. In this study, green synthesis of RGOX was functionally verified by employing FTIR and UV-visible spectroscopy, along with SEM and TEM. Our results demonstrated typical morphology of RGOX stacked in layers that appeared as silky, transparent, and rippled. The antibacterial activity was shown by analyzing minimal inhibitory concentration values, agar diffusion assay, fluorescence techniques. It showed enhanced antibacterial activity against Gram-positive and Gram-negative bacteria in comparison to GOX. It has also been shown that the synthesized compound exhibited enhanced antibiofilm activity as compared to its parent compound. The efficacy of RGOX and GOX has been demonstrated on a human breast cancer cell line, which suggested RGOX as a potential anticancer agent.

Graphene (G) is a 2D material of sp2 hybridized carbon atoms, discovered by Geim and Novoselov in 2004. The material presents a wide range of peculiar electronics and thermal, optical, mechanical, structural, and surface properties, which have attracted considerable interest from researchers and technologists. The conevntional techniques for graphenization have presented some drawbacks including low yield, costliness, high chances of contamination, and their time-consuming nature. These limitations have led to proliferation of research, which has led to the discovery of more advanced techniques for G synthesis over the years. At the moment, trending approaches to G production include chemical vapor disposition (CVD), epitaxial growth on silicon carbide (SiC), G oxide reduction, chemical synthesis, electrochemical synthesis, and laser-induced graphenization. There is a growing demand to produce G in large quantities and good quality. Nonetheless, because the conventional techniques have presented significant difficulties and imperfections in large-scale G production, various investigations have been conducted to identify new techniques for manufacturing cost-effective, large-scale, and high-quality G with novel applications such as energy storage, sensors, drug delivery, and biomedical devices. Each technique can be used for certain applications and has its own advantages. This chapter deals with the two approaches (top-down and bottom-up) for the synthesis of G and their procedure, limitations, and applications.