A novel catalytic-type gas sensor based on alumina ceramic substrates loaded with catalysts and printed electrodes

Abstract

l The porous alumina ceramics act as the supports of catalysts and the substrates of Pt heating electrodes, simultaneously. l The preparation of platinum electrodes in batch enable sensors with a high uniformity. l The high sensitivity and stability of prototype H 2 sensors was achieved. l Heat transfer analysis by FEM modeling was carried out to verify the sensing performance of H 2 sensors. Catalytic combustion gas sensors have been widely used for leakage detection of combustible gases. Therefore, the catalytic sensor with low preparation cost and high repeatability in a mass production has great importance. In this view, a new structure of high-performance catalytic sensor was proposed. Catalytic-type gas sensors based on screen-printing Platinum (Pt) heating electrode onto a porous alumina substrate was fabricated. This design enables porous alumina ceramics to act as the support of catalyst and substrate of heating electrode, simultaneously. The screen-printing technique obviously enhances the uniformity of the sensor devices in batch. To demonstrate the feasibility of this design, a prototype hydrogen sensor was prepared with a relatively high sensitivity around 30 mV/Vol% at 245°C and an excellent long-term stability. Additionally, sensing performances of hydrogen devices were also verified by finite element method (FEM) modeling. The simulation results suggested that the response time and response value were related to the thickness of substrate and the operating temperature of sensors. The facile and large-scale fabrication method of the sensor device in this work is expected to have potential utility for industrial detection and for personalized applications. .