GRAPHENE-BASED NANOMATERIALS: CHEMICAL PROPERTIES AND ELECTRONIC APPLICATIONS

Abstract

Graphene-based nanomaterials have attracted intense research interest due to the combination of an exceptionally rich surface chemistry and outstanding electronic performance that makes them promising candidates for transistors, sensors, flexible electronics, energy systems and environmental applications. This review systematically explores the chemical properties and electronic applications of graphene and its derivatives, especially graphene oxide, reduced graphene oxide and their functionalized forms, on an evidence base of ten recent peer-reviewed publications published between 2020 and 2025. The synthesis literature describes two complementary pathways, top-down strategies that break bulk materials down into nanoscale building blocks and bottom-up strategies that build nanostructures from molecular precursors, with shared bottlenecks in defect control and high energy requirements. Functional modification, i.e. covalent binding, non-covalent binding and elemental doping, provides the central mechanism at the chemical level to tune the electronic, optical and chemical behaviour of these materials. Chemical or thermal reduction restores conductivity without completely removing the functional groups that allow further modification. In electronics, two-dimensional materials have atomic thickness, which confines carrier flow to the surface of the material and exposes it directly to the environment, allowing for efficient signal acquisition and conversion in field-effect transistor sensors. Flexible graphene field-effect transistors have been demonstrated to sense proteins, glucose and ions in a label-free manner, enabling wearable and implantable biomedical monitoring. Graphene applications are not limited to electronics, graphene-based nanomaterials increase the mechanical strength, fire resistance and impermeability of cement-based and geopolymer construction materials. Graphene hybrid systems are considered as effective platforms for environmental remediation and energy applications. However, scalable production of defect-free graphene, standardised functionalization protocols, device reliability and commercialisation remain unsolved. The review concludes that graphene-based nanomaterials are best viewed as a chemically programmable platform where device performance is achieved through deliberate surface design and suggests future directions that bridge chemistry and device engineering.