Abstract
Graphene and its derivatives, such as graphene oxide, have a wide range of applications in industry, especially in electronics, electrode construction, catalyst in electro- and photocatalytic reactions, etc. This work presents results from the synthesis of graphene oxide sheets (GOs) from rice husks ash and its modification by incorporating copper nanoparticles. Rice husks, a low-value waste product generated in large quantities, were thermally treated to obtain a mixture of natural carbons with silica. This carbonaceous material was then reacted with potassium hydroxide to produce GOs. The GOs were modified using an impregnation and reduction process to immobilize copper metal nanoparticles onto their surface and obtain graphene oxide with CuO nanoparticles in their surface (GOs-CuO). The synthesized composites were characterized by FTIR, SEM, BET, XRD, and AFM, demonstrating that the formed structure is composed of graphene with predominantly copper oxide nanoparticles adsorbed on its surface. The band gap for the synthesized structures was determined by finding a significant decrease in the band gap of graphene oxide when copper nanoparticles are incorporated. Catalytic capacities of synthetized samples were tested in the decomposition reaction of pollutants, using Rhodamine B (RhB) as a model molecule due to its environmental persistence and toxicity. Both GOs and GOs-CuO effectively degraded RhB, with GOs-CuO demonstrating a 8-fold faster kinetic rate, highlighting its potential for pollutant remediation applications.