Synthesis of a Ag/rGO nanocomposite using Bos taurus indicus urine for nitroarene reduction and biological activity

The present study develops a unique in situ synthesis of a catalytically and biologically active Ag/reduced graphene oxide (rGO) nanocomposite. Herein, we employed Bos taurus indicus urine to synthesize a Ag/rGO nanocomposite in an environmentally benign, facile, economical, and sustainable manner. The elemental composition analysis reveals the presence of Ag, O and C elements. The scanning electron micrograph shows the formation of spherical silver in nanoform whereas rGO is found to be flake shaped with a wrinkled nature. The synthesized nanomaterial and its composite shows a positive catalytic effect in simple organic transformation for the reduction of nitroarene compounds. Investigations were conducted into the catalytic effectiveness of the prepared nanomaterials for diverse nitroarene reduction. Then, using NaBH(4) at 25 °C, the catalytic roles of Ag and the Ag/rGO nano-catalyst were assessed towards the catalytic reduction of several environmental pollutants such as 2-, 3- and 4-nitroaniline and 4-nitrophenol into their respective amino compounds. To test their catalytic performance, bio-mimetically synthesized Ag NPs were thermally treated at 200 °C and compared with the Ag/rGO nanocomposite. Furthermore, biomedical applications such as the antibacterial and antioxidant properties of the as-prepared nanomaterials were investigated in this study.