PZT-PDMS based Printed Acoustic Sensor for CO2 Sensing

In this work, a printed flexural plate wave (FPW) CO
2
sensor based on PZT-PDMS (Lead zirconate titanate-Polydimethylsiloxane) is prepared with simple fabrication techniques. The 2-port FPW resonator has a resonant frequency of 21.51 MHz with a low insertion loss of -3.3 dBm. Multi-Walled Carbon Nanotubes (MWCNT) solution is applied as sensing layer to measure CO
2
concentration in the surrounding. The sensitivity and limit of detection (LOD) of the sensor are measured to be 504 Hz/ppm and 6.7 ppm, respectively. The sensor shows good repeatability, response and recoveries to varying CO
2
concentrations. With adaptability to roll to roll (R2R) printing methods, this inexpensive and prototype FPW gas sensor shows potential for low concentration measurement of CO
2
.