Review of surface acoustic wave-based hydrogen sensor

Hydrogen (H2) sensors with excellent performance play an important role in the safety application of H2 energy. Among current H2 detection technologies, surface acoustic wave (SAW) based H2 sensors attract more attention due to their features of high sensitivity, fast response, mico-nano scale and excellent stability, which was composed of a SAW sensing chip and sensing materials depositing along the acoustic wave propagation path, and utilizing the coupling mechanism of force-acoustic-electric multiple physical fields. Here we review the SAW H2 sensor, focusing on the H2 sensing materials, SAW sensing mechanisms, sensing devices, sensing circuits, and development status. And prospects were made for its development trends and challenges.