In this introductory lecture, we began by analyzing and describing the history of the element carbon and carbonaceous materials in a very general context. The element carbon, discovered by Antoine Lavoisier in 1772, is mainly produced by nucleosynthesis in red giant stars through the fusion of three helium nuclei. It is the fourth most abundant element in the Universe, after hydrogen, helium and oxygen. On Earth, it is mainly (99.95%) trapped in minerals such as chalk and calcium carbonate. Its electronic structure and electronegativity open up numerous possibilities for hybridization and association with other elements, giving rise to a wealth of structures found in numerous organic molecules and architectures, as well as a wide variety of carbonaceous materials (carbons). As a result, carbon is the essential building block of life's structures; the human body, for example, contains 18% carbon. We then established the links between the element carbon and carbons by following two main routes: one literary and the other geological. In the first, we rediscovered Primo Levi's book The PeriodicSystem1, in which the author, a doctor of chemistry, takes the element carbon on a journey that is both chemical and literary, from chalk to the biological matter that makes up the brain. This triggers the act of writing with a pencil whose lead is made from a carbon-graphite composite. We then described the formation of natural carbonaceous materials (peat, lignite, hard coal, anthracite, etc.), which began in the Carboniferous period, following diagenesis and then metamorphism processes. Extreme geological conditions (high pressures and temperatures) led to the crystallization of these carbonaceous materials, mainly in crystalline forms with diamond or graphite structures. We then described the history of carbonaceous materials in mankind, from the prehistoric artist's gesture of using the black color of carbon to create frescoes and drawings, to the recent advent of nanotechnologies, using new carbonaceous materials such as nanodiamonds, fullerenes, carbon nanotubes and graphenes. This long journey through time has enabled us to retrace the major role played by the various carbons and carbons that have been used from 3,750 BC to the present day as filters, adsorbers, energy sources (steam engines, industrial and domestic heating, lighting gases, power stations, etc.) or as compounds involved in the synthesis of metallic materials from heavy industries (iron and steel, aluminum metallurgy, etc.). The science of carbon, on the other hand, only really began in the 18thcentury and developed over the following two centuries. It was built up both through application projects (filters, bleaches, current conductors for incandescent lamps, coke in blast furnaces, cast irons and steels, etc.) and fundamental projects (adsorption theory, structural analysis, metal-carbon phase diagrams, discovery of new carbons and study of their physical properties, etc.). Carbon has truly been the vector of the industrial revolutions that took place towards the end of our second millennium. The last twenty years have been an exciting period for the field of carbonaceous materials; their discovery or rediscovery has attracted the attention and imagination of many researchers around the world. Enormous research and development efforts have been devoted to studying these new carbon allotropes (nanodiamonds, fullerenes, carbon nanotubes, graphenes, etc.). The results obtained have considerably extended our understanding of fundamental science at the nanoscale, and created opportunities for future technologies. Indeed, these new carbon nanomaterials - with three-, two-, one- or zero-dimensional structures emerging from research laboratories - do not appear to be outdone by their predecessors, their exceptional properties (electronic, mechanical, density, etc.) raising a large number of fundamental questions and already opening the way to numerous possible applications in the fields of energy, the environment, information and communication science and technology, and health.
[1].primo Levi, Le Système périodique [1975], Paris, Albin Michel, 1987.
