Trial of an All-Ceramic SnO₂ Gas Sensor Equipped with CaCu₃Ru₄O12 Heater and Electrode.

We have constructed a gas sensor of SnO₂ equipped with ceramic electrodes and a heater made of CaCu₃Ru₄O12, which demonstrated good device performance at high temperature. The CaCu₃Ru₄O12-based electrodes and heater were formed on Al₂O₃ substrates using a screen-printing process, which is cost-effective and suitable for mass-production. This all-ceramic device reached 600 °C at the lowest, and remained intact after one week of operation at 500 °C and rapid thermal cycling of 500 °C temperature changes within 10 s. We propose CaCu₃Ru₄O12 as a robust and reliable conducting material that can be a substitute for Pt in various devices.