Gallium Nitride and Oxonitrides

New nitrides: from high pressure–high temperature synthesis to layered nanomaterials and energy applications

“…Nitride materials form an important class of solidstate compounds with useful functional properties, ranging from refractory ceramics such as Si 3 N 4 and AlN, to (Ga,In,Al)N wide-gap semiconductors, high-T c superconductors (NbN) and high-hardness metallic nitrides (MoN, TiN), that are also useful catalysts. However, despite major advances made over the past two decades, the field of nitride solid-state chemistry remains under-explored compared with that of oxide materials [1][2][3] compounds dominated by intermetallic bonding and they do not typically achieve the highest oxidation states found among corresponding oxide compounds (e.g. TiN versus TiO 2 ; MoN versus MoO 3 , etc.).…”

“…These studies have been greatly facilitated by synchrotron X-ray diffraction, as well as by neutron scattering techniques to investigate the progress of the reactions and the structures formed. Work on main group nitrides has focused on materials and compounds formed with groups 13-15 elements, including Si, Ge and Ga, that give rise to wide-gap semiconducting ceramics [2]. Here synchrotron X-ray diffraction and investigations of the electronic structure using X-ray absorption (XAS) and emission measurements combined with ab initio theoretical calculations have been key to exploring and establishing the optoelectronic properties of this potentially important family of materials.…”