The aim of this project is the high-pressure / high-temperature synthesis of new oxonitride phases in the system MN-M2O3 (M = Ga, In). The new materials will be synthesized via the transformation of special compounds and starting materials by applying HP/HT conditions using laser-heated diamond anvil cells, an in-situ X-ray multianvil device, and a Walker-type multianvil press. In a first step, new gallium oxonitrides with a varying molar composition will be synthesized with a close view to their structural and physical properties depending on the N/O-ratio. These investigations will be accompanied by extensive quantum mechanical calculations resulting in a target-oriented synthetic strategy, which will lead to a precise phase diagram of the system GaN-Ga2O3. In a second step, these systematic investigations will be extended on the system InN / In2O3, entering a new high-density oxonitride system, in which no compounds exist until now. Furthermore, the investigations will be expanded to solid solutions, e.g. (Al, Ga, In) oxonitrides. The planned HP/HT experiments open up a new class of materials, which is not accessible using a conventional synthetic strategy under ambient pressure conditions. Following this way, unknown areas of stability with new crystal structures and material properties will be investigated.
DFG Programme
Priority Programmes
