Carbon-based nanomaterials from a historical perspective

Carbon, an ancient element, is still fascinating us with its flexibility to be transformed into different materials via its different degrees of hybridization (sp, sp², and sp³). After the structural identification in the beginning of the 20th century by John D. Bernal, graphite became a material of intense study. In the 1950s and 1960s, the physics and chemistry of graphite started to be developed from both theoretical and experimental perspectives. Soon after, graphite intercalation compounds and the synthesis of carbon microfibers became popular, and then in 1985, the era of nanocarbons started with the discovery of fullerenes (carbon cage molecules), followed by the structural identification of nanotubes and the isolation of graphene. Today, these three novel nanocarbons are being intensively studied and the physico-chemical properties are different among the three. This review intends to provide a historical perspective of these novel forms of carbon and their impact on electronics and other fields. We believe that, within a short time, commercial products based on any of these materials will be a reality but further experimental and theoretical research is still needed in some areas, as well as the development of low-cost production processes for commercial materials, devices, and products.