Ricerc@Sapienza

Hydrogen is the smallest and one of the most reactive atoms. H diffuses easily in solids and interacts strongly with the electronic charge distribution. Furthermore, H is present in most growth processes and device mass-production steps. For these reasons, a great interest has been focused on the effects of H in insulators and semiconductors. In particular, the deliberate and controllable incorporation of H in crystals is extremely important since, on the one side, it allows understanding the best approaches to eventually cage H in solids and, on the other hand, it represents a means to modify on demand the electronic and structural properties of materials.
In this proposal, we apply for the purchase of a low-energy ion Kaufman source. This kind of system is particularly suited for studying the effects of H in solids thanks to the low energy (10-100 eV) of the ion beams employed. Indeed, such low energies increase considerably the cross-section of interaction between the ions and unpaired chemical bond distribution in the crystal and facilitate H incorporation. The Kaufman source will be used on a broad range of materials addressing the interests of many research groups. The aim is to investigate the electronic and optoelectronic properties of quantum materials (such as graphene, transition metal dichalcogenides, hexagonal boron nitride) and their heterostructures, of excitonic and topological insulators, and to augment the H storage capability in solid matrices (like metal hydrides and metal-organic frameworks) for energy applications. Moreover, the study of H and deuterium loading on single layer graphene is also relevant to predict the capability to load tritium on graphene - a key element in the design of next generation experiments to measure the mass of the electron neutrino or for a future observatory of the cosmic neutrino background, a messenger from the very early Universe.