Next Article in Journal
TD-LSTM: Temporal Dependence-Based LSTM Networks for Marine Temperature Prediction
Next Article in Special Issue
Fast and Accurate Finite Transducer Analysis Method for Wireless Passive Impedance-Loaded SAW Sensors
Previous Article in Journal
Mitigation of CSI Temporal Phase Rotation with B2B Calibration Method for Fine-Grained Motion Detection Analysis on Commodity Wi-Fi Devices
Previous Article in Special Issue
Enhanced Sensitivity of a Love Wave-Based Methane Gas Sensor Incorporating a Cryptophane-A Thin Film
Article Menu

Export Article

Open AccessArticle
Sensors 2018, 18(11), 3796; https://doi.org/10.3390/s18113796

Enhanced Sensitivity of a Hydrogen Sulfide Sensor Based on Surface Acoustic Waves at Room Temperature

1
Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China
2
School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100190, China
3
State Key Laboratory of NBC Protection for Civilian, Beijing 102205, China
*
Authors to whom correspondence should be addressed.
Received: 11 October 2018 / Revised: 1 November 2018 / Accepted: 2 November 2018 / Published: 6 November 2018
(This article belongs to the Special Issue Surface Acoustic Wave Sensors)
Full-Text   |   PDF [3877 KB, uploaded 6 November 2018]   |  

Abstract

In this contribution, a new surface acoustic wave (SAW)-based sensor was proposed for sensing hydrogen sulfide (H2S) at room temperature (30 °C), which was composed of a phase discrimination circuit, a SAW-sensing device patterned with delay line, and a triethanolamine (TEA) coating along the SAW propagation path of the sensing device. The TEA was chosen as the sensitive interface for H2S sensing, owing to the high adsorption efficiency by van der Waals’ interactions and hydrogen bonds with H2S molecules at room temperature. The adsorption in TEA towards H2S modulates the SAW propagation, and the change in the corresponding phase was converted into voltage signal proportional to H2S concentration was collected as the sensor signal. A SAW delay line patterned on Y-cut quartz substrate with Al metallization was developed photographically, and lower insertion and excellent temperature stability were achieved thanks to the single-phase unidirectional transducers (SPUDTs) and lower cross-sensitivity of the piezoelectric substrate. The synthesized TEA by the reaction of ethylene oxide and ammonia was dropped into the SAW propagation path of the developed SAW device to build the H2S sensor. The developed SAW sensor was characterized by being collecting into the phase discrimination circuit. The gas experimental results appear that fast response (7 s at 4 ppm H2S), high sensitivity (0.152 mV/ppm) and lower detection limit (0.15 ppm) were achieved at room temperature. It means the proposed SAW sensor will be promising for H2S sensing. View Full-Text
Keywords: surface acoustic wave (SAW); hydrogen sulfide (H2S); triethanolamine (TEA); phase discrimination; room temperature surface acoustic wave (SAW); hydrogen sulfide (H2S); triethanolamine (TEA); phase discrimination; room temperature
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Liu, X.; Wang, W.; Zhang, Y.; Pan, Y.; Liang, Y.; Li, J. Enhanced Sensitivity of a Hydrogen Sulfide Sensor Based on Surface Acoustic Waves at Room Temperature. Sensors 2018, 18, 3796.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Sensors EISSN 1424-8220 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top