Entwicklung und Anwendung von Hochdurchsatztechniken zur Darstellung und Untersuchung neuer nanostrukturierter Sensormaterialien

摘要

For the development of new gas sensor materials surface and volume doped nanoscalic metal oxides were investigated, whereas high-throughput techniques were applied. The necessary synthesis and characterisation methods were provided by modification of a pipetting robot for a parallel material synthesis and sample deposition on special multi-electrode substrates, as well as the further development of a screening reactor and single sensor test station. Making use of the polyol method opened a simple synthetic access to nanoscalic metal oxides like ZnO, In2O3 and SnO2, which were used as basic materials for the preparation of highly diverse functionalised surface and volume doped material libraries. To acquire their sensoric properties a screening program was used which comprised of test gases of H2, CO, NO, NO2 and C3H6 in synthetic air in the temperature range from 523 to 673 K. To analyse the resulting high amounts of data the Q/S-plot was developed and applied, which enables by comparing the relative selectivity and sensitivity a fast visual identification of the best promising material combinations. As an example doping by silver cluster led to a distinct increase of the sensitivity of various metal oxides against hydrogen; a mixture of rhodium, gold and palladium increased the sensoric properties of SnO2 towards the detection of CO, whereas using silver as a dopant increased distinctly the response to NO2. These screening results were further investigated by making use of single sensor elements, whereas e.g. the silver doped SnO2 showed an extrapolated limit of detection of about 100 ppb of NO2.