Surface Acoustic Wave DMMP Gas Sensor with a Porous Graphene/PVDF Molecularly Imprinted Sensing Membrane

Abstract

In this paper, surface acoustic wave (SAW) sensors containing porous graphene/PVDF (polyvinylidene fluoride) molecularly imprinted sensitive membrane for DMMP gas detection were investigated. A 433 MHz ST-cut quartz SAW resonator was used to convert gas concentration changes into frequency shifts by the sensors. The porous graphene/PVDF film was fabricated on the sensor’s surface by using the tape-casting method. DMMP molecules were adsorbed on the porous structure sensing film prepared by the 2-step method to achieve the specific recognition effect. The sensitivity of the sensor could reach −1.407 kHz·ppm−1. The response time and recovery time of the SAW sensor with porous graphene/PVDF sensing membrane were about 4.5 s and 5.8 s at the concentration of 10 ppm, respectively. The sensor has good anti-interference ability to most gases in the air.

Surface Acoustic Wave (SAW) Sensors: Physics, Materials, and Applications

“…For these purposes, the selection of a highly sensitive and selective sensing membrane is desired for the SAW sensors. Although a wide range of materials is used as sensing membranes, these membranes are majorly categorized into polymers, semiconductors, and graphene-based sensing films [ 164 ]. The selection of a suitable sensing membrane involves several factors such as good selectivity of the target molecules or analytes, high response, stability, low-cost, and most of all, good biocompatibility with low toxicity [ 165 ].…”

Smart and Multifunctional Materials Based on Electroactive Poly(vinylidene fluoride): Recent Advances and Opportunities in Sensors, Actuators, Energy, Environmental, and Biomedical Applications

“…More recently, Xu et al 202 incorporated porous PVDF/Gr membranes on surface acoustic wave sensors to increase the sensor's response time. The sensitivity of the dimethyl methyl phosphonate (DMMP) sensor reached the remarkable value of −1.407 kHz•ppm −1 , the response time and recovery time of the sensor being improved 4.5 and 5.8 s, respectively, with the incorporation of the PVDF/Gr membranes.…”

Surface acoustic wave induced phenomena in two-dimensional materials

“…Therefore, SAWs emerge as a fantastic means for exciting solid-state materials in coordination with electrons and photons or magnetic and spin excitations. 3,4 To date, by employing acousto-electric, acousto-optic and magneto-elastic coupling effects, phononic circuits and resonators have been widely adopted to guide, circulate and modulate SAWs for sensing [5][6][7][8] and communications, 9,10 especially in life sciences and acoustic microfluidics for sensing and mixing tiny amounts of liquids. [11][12][13] Fundamentally, the propagation velocity (n SAW ) of SAWs in solids usually reaches a few thousand meters per second and SAWs with the same frequency with electromagnetic waves possess five orders of magnitude shorter wavelength, showing great potential in device miniaturizations.…”