This work reports wireless ceramic chemical sensors operating in high temperature environments. The sensors utilize a passive wireless resonant telemetry scheme to eliminate the need for onboard power and exposed interconnects. An inductorcapacitor (LC) resonator circuit forms the basis for the wireless platform. The sensor inductor is fabricated from electroplated nickel and the capacitor portion of the circuit is fabricated using mixed-oxide ceramic dielectrics. These dielectrics are found to

more »

... exhibit variations in electrical properties with exposure to differing concentrations of CO 2 and NO x . Dual sensing schemes are presented that utilize the two observed electrical responses in these materials; conductivity changes for CO 2 detection and permittivity changes for NO x detection. CO 2 sensors have been fabricated that are able to function up to 675ºC. NO x sensors capable of operating at up to 600ºC, while detecting NO concentrations below 5ppm, are also presented.