A combinatorial technique for the search of solid state gas sensor materials

A complete high throughput assembly for the search for electrochemical sensor materials is described. It is a primary screening device, whose sole purpose is to locate most efficiently new materials with potential sensor properties. The set-up consists of a gas tight reactor for the sensor libraries, an IR-camera, a switching multimeter for dc-resistance measurements, a test gas supply array for different test gases, software for control of experimental flow, data recording, data evaluation, data mining and a database. The sensor libraries consist of a ceramic alumina plate with 64 interdigital electrodes and associated contact pads arranged on the outer rim of the library. The materials are deposited on top of the electrodes and calcined before use. The reactor houses 128 spring loaded electrodes for electrochemical monitoring and a sapphire plate for IR-monitoring of materials responses to exposure to test gases. Data are evaluated automatically and stored in a database for visualization and data mining.