Transition metal complexes in chemical sensing


Traditional materials for solid-state chemoresistive gas sensors are semiconductor materials like metalloids, semiconductor metal oxides or organic semiconductors. Transition metal complexes are a very promising class of materials, which are mostly overlooked. They offer, depending on the transition metal ion and the design of the ligands, the possibility of various features with the desired chemical and electronic structure. These compounds are therefore suitable candidates for multiple applications such as gas/chemical sensing. Within this project, new coordination complexes (using transition metals such as Ni, Cu and other potentially attractive metals) will be developed and synthesised (in collaboration with Karlsruhe Institute of Technology). The ligands will be designed appropriately and combined with the late first row transition metal ions to lead to the desired structural vacancies. In a second step, these complexes will be used for thin film processing in order to test them as active layer for gas detection. The preparation and analysis of the thin films is crucial to use them for selective and sensitive detection of harmful and toxic gas analytes. The attention will be aimed to chemoresistive and optical gas detection principles. Theoretical calculations (done in collaboration with the Max Planck Institute) will help to understand the sensing mechanism and provide a route to develop and improve the complex design in a systematic way.