GRAAL

The fundamental study and engineering of defective carbon materials (DCM) could allow major advances in various fields such as information storage, nanoelectronics and catalysis. The proposed consortium involving chemists and physicists aims at developing a simple and scalable process to produce DCM, study their physical properties and assess their chemical reactivity, as a carbene-like behavior is expected. To achieve these goals, the synthesis of carbene-like molecular models (CMM) containing well-defined defects will be of great help, along with electronic structure calculations based on density functional theory, complemented by conventional magnetometry and anomalous Hall effect measurements in transport devices. The chemical reactivity of DCM and CMM will then be investigated on model catalytic reactions. The innovative idea of the GRAAL project is based on a recent discovery made by some of the project partners. This is a thermochemical process for preparing DCM which allows the introduction of controlled quantities of defects by a surface functionalization step introducing various types of oxygenated groups followed by a selective defunctionalization step at relatively low temperature. The exact nature of the localized electronic states created by this thermochemical process is not yet known and definitely deserves more attention. More precisely, within the GRAAL project, we intend to: (i) produce on a large scale and characterize various DCM (carbon nanotubes, graphene, carbon nanofibers); (ii) understand the physics of these systems (magnetism, transport) by combining atomic-scale property calculations and advanced characterization tools; (iii) study the chemical reactivity of these materials by comparison with molecular models containing well-defined zigzag-type edges; and (iv) study the chemical reactivity of CMM and DCM, which could ultimately be considered solid carbenic species. We believe that the results obtained within the framework of the GRAAL project will allow major advances for the surface science of carbon materials, for which the physical (free radicals, edge states) and chemical (carbene type) visions of graphene edges must to be reconciled; but also in homogeneous and heterogeneous catalysis (new molecular carbenes, solid carbenes).