Wireless passive surface acoustic wave (SAW) technology in gas sensing

Abstract

Purpose This paper aims to give an overview about the state of wireless passive surface acoustic wave (SAW) gas sensor used in the detection of chemical vapor. It also discusses a variety of different architectures including delay line and array sensor for gas detection, and it is considered that this technology has a good application prospect. Design/methodology/approach The authors state the most of the wireless passive SAW methods used in gas sensing, such as CO2, CO, CH4, C2H4, NH3, NO2, et al., the sensor principles, design procedures and technological issues are discussed in detail; their advantages and disadvantages are also summarized. In conclusion, it gives a prospect of wireless passive SAW sensor applications and proposes the future research field might lie in the studying of many kinds of harmful gases. Findings In this paper, the authors will try to cover most of the important methods used in gas sensing and their recent developments. Although wireless passive SAW sensors have been used successfully in harsh environments for the monitoring of temperature or pressure, the using in chemical gases are seldom reported. This review paper gives a survey of the present state of wireless passive SAW sensor in gas detection and suggests new and exciting perspectives of wireless passive SAW gas sensor technology. Research limitations/implications The authors will review most of the methods used in wireless passive SAW sensor and discuss the current research status and development trend; the potential application in future is also forecasted. Originality/value The authors will review most of the methods used in wireless passive SAW sensor and discuss the current research status and development trend; the potential application in future is also forecasted.

Investigation of Elastic Properties of WO3 Thin Films Supported on Quartz in Surface Acoustic Wave Sensing Devices

“…The enthusiasm over SAW devices originates in its easyto-use and highly sensitive characteristics. The working principle is the measurement of the modification of the surface propagating wave due to the interaction of the active material with a specific gas molecule [1][2][3][4]. Indeed, the surface wave resonator, which is confined within few wavelengths of the piezoelectric crystal surface, is strongly sensitive to any changes in the physical and/or chemical properties of the thin active layer (as in the present study) [5].…”

Recent Development of Hierarchical Metal Oxides Based Gas Sensors: From Gas Sensing Performance to Applications

“…[ 8–10 ] Conventionally, several technologies can be used to detect gases, such as quartz crystal microbalance, surface acoustic wave, optical transducers, etc. [ 11–13 ] Nevertheless, these technologies often need bulky and expensive equipments or complex and professional operation process, and then are not suitable to be used in daily life. From the perspective of application, because of the small size, low cost, and easy usage, the metal oxide‐based gas sensors have their incomparable advantages and have become the focus of research in this field.…”

Recent Progress on Nanomaterials for NO2 Surface Acoustic Wave Sensors

“…In recent years, different types of NO 2 sensors have been developed based on sensing materials, fabrication technologies, input signals and conversion mechanism or sensor features (such as cost, stability or accuracy). Most studied NO 2 sensors are metal oxide semiconductor sensors [4][5][6][7], catalytic-type sensors [8], electrochemical sensors [9,10] and acoustic-based sensors [11][12][13].…”