Surface Acoustic Wave H2 and O2 Sensors Based on Conducting Metal Oxides/Langasite for Elevated Temperature Applications

Surface acoustic wave (SAW) sensors are promising candidates for gas species sensing at various conditions ranging from room temperature to high temperatures when functionalized with relevant sensing materials. At increased temperatures, limited sensing materials are available for integration with these devices. Conducting oxides such as indium oxide (IO) or indium tin oxide (ITO) are promising sensing layers for conductivity-based SAW sensors at temperatures below 500°C. In our work, we developed a reflective delay line sensor on langasite (LGS) with IO and ITO sensing layers for H
₂
and O
₂
for applications at 350 °C.