Facile synthesis of reduced graphene oxide films at the air–water interface and in situ loading of noble metal nanoparticles

K Bramhaiah and Neena S John

Abstract

Transparent free-standing films of reduced graphene oxide (RGO) are obtained from graphene oxide solution at the air–water interface in a simple, rapid, one-step reduction process with tetrakis(hydroxymethyl)phosphonium chloride (THPC), a widely used reducing agent for synthesizing metal nanoparticles from metal salts. The thickness of the films depends on the initial concentration of graphene oxide (GO). The restoration of the aromatic basal plane network and the removal of oxygen groups are confirmed by UV-visible and infrared spectroscopies. Atomic force microscopy shows that the film consists of a self-assembled monolayer of RGO platelets that are continuous over micrometre scale areas. In the presence of noble metal ions, THPC reduces both GO and metal ions to form free-standing films of RGO decorated by noble metal nanoparticles. Compared to other reported methods, the THPC route offers a very rapid and one-step process to obtain ultra-thin films of RGO loaded with noble metal nanoparticles