Multi-Gas Detection System Based on Non-Dispersive Infrared (NDIR) Spectral Technology

Xu, M.; Peng, Bo; Zhu, Xiangyi; Guo, Yongcai

doi:10.3390/s22030836

Cited by 31 publications

(19 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To the best of our knowledge, this is the first demonstration of a functional small NDIR CO 2 gas sensor using a 20% ScAlN-based pyroelectric detector. Table shows a comparison of the size and performance of recently reported NDIR CO 2 gas sensors using broadband sources and microelectromechanical systems (MEMS) detectors for environmental monitoring, published within the past 2 years. ,,,− For NDIR gas sensors which are known for their large footprints, size reduction could bring about a compromise in the lowest detection limit and response time. This can be seen in Table by an NDIR gas sensor with lowest CO 2 detection limit reported at 2 ppm.…”

Section: Resultsmentioning

confidence: 99%

Miniaturized CO₂ Gas Sensor Using 20% ScAlN-Based Pyroelectric Detector

Liang

Chen

et al. 2022

ACS Sens.

View full text Add to dashboard Cite

NDIR CO 2 gas sensors using a 10-cm-long gas channel and CMOS-compatible 12% doped ScAlN pyroelectric detector have previously demonstrated detection limits down to 25 ppm and fast response time of ∼2 s. Here, we increase the doping concentration of Sc to 20% in our ScAlN-based pyroelectric detector and miniaturize the gas channel by ∼65× volume with length reduction from 10 to 4 cm and diameter reduction from 5 to 1 mm. The CMOS-compatible 20% ScAlN-based pyroelectric detectors are fabricated over 8-in. wafers, allowing cost reduction leveraging on semiconductor manufacturing. Cross-sectional TEM images show the presence of abnormally oriented grains in the 20% ScAlN sensing layer in the pyroelectric detector stack. Optically, the absorption spectrum of the pyroelectric detector stack across the mid-infrared wavelength region shows ∼50% absorption at the CO 2 absorption wavelength of 4.26 μm. The pyroelectric coefficient of these 20% ScAlN with abnormally oriented grains shows, in general, a higher value compared to that for 12% ScAlN. While keeping the temperature variation constant at 2 °C, we note that the pyroelectric coefficient seems to increase with background temperature. CO 2 gas responses are measured for 20% ScAlN-based pyroelectric detectors in both 10-cm-long and 4-cm-long gas channels, respectively. The results show that for the miniaturized CO 2 gas sensor, we are able to measure the gas response from 5000 ppm down to 100 ppm of CO 2 gas concentration with CO 2 gas response time of ∼5 s, sufficient for practical applications as the average outdoor CO 2 level is ∼400 ppm. The selectivity of this miniaturized CO 2 gas sensor is also tested by mixing CO 2 with nitrogen and 49% sulfur hexafluoride, respectively. The results show high selectivity to CO 2 with nitrogen and 49% sulfur hexafluoride each causing a minimum ∼0.39% and ∼0.36% signal voltage change, respectively. These results bring promise to compact and miniature low cost CO 2 gas sensors based on pyroelectric detectors, which could possibly be integrated with consumer electronics for real-time air quality monitoring.

show abstract

Section: Resultsmentioning

confidence: 99%

Miniaturized CO₂ Gas Sensor Using 20% ScAlN-Based Pyroelectric Detector

Liang

Chen

et al. 2022

ACS Sens.

View full text Add to dashboard Cite

show abstract

“…They achieved multi-gas sensing with nanoantenna integrated narrowband pyroelectric detectors instead of multiple pairs of bulky and expensive bandpass filters and detectors [ 86 ]. A similar system was shown by Xu et al to be able to analyze multiple automobile exhaust gases simultaneously [ 87 ]. Esfahani et al demonstrated that NDIRs can also be used as sensors in an electronic nose, overcoming common issues such as sensor drift, poor repeatability, lack of robustness, insufficient replicability and temperature and humidity effects [ 88 ].…”

Section: Fast/screening Methods For On-site/mobile Analysis Of Vocsmentioning

confidence: 99%

On-Site Detection of Volatile Organic Compounds (VOCs)

Epping

Koch

2023

Molecules

View full text Add to dashboard Cite

Volatile organic compounds (VOCs) are of interest in many different fields. Among them are food and fragrance analysis, environmental and atmospheric research, industrial applications, security or medical and life science. In the past, the characterization of these compounds was mostly performed via sample collection and off-site analysis with gas chromatography coupled to mass spectrometry (GC-MS) as the gold standard. While powerful, this method also has several drawbacks such as being slow, expensive, and demanding on the user. For decades, intense research has been dedicated to find methods for fast VOC analysis on-site with time and spatial resolution. We present the working principles of the most important, utilized, and researched technologies for this purpose and highlight important publications from the last five years. In this overview, non-selective gas sensors, electronic noses, spectroscopic methods, miniaturized gas chromatography, ion mobility spectrometry and direct injection mass spectrometry are covered. The advantages and limitations of the different methods are compared. Finally, we give our outlook into the future progression of this field of research.

show abstract

“…Optics-based methods have several advantages and are widely used in trace gas monitoring. Non-dispersive infrared (NDIR) has been increasingly applied to atmospheric CO 2 and H 2 O monitoring [ 5 , 6 , 7 ]. However, the application of NDIR is limited because it uses a broadband light source and therefore has poor selectivity.…”

Section: Introductionmentioning

confidence: 99%

Portable TDLAS Sensor for Online Monitoring of CO2 and H2O Using a Miniaturized Multi-Pass Cell

Chen

Zhang³

et al. 2023

Sensors

View full text Add to dashboard Cite

We designed a tunable diode laser absorption spectroscopy (TDLAS) sensor for the online monitoring of CO2 and H2O concentrations. It comprised a small self-design multi-pass cell, homemade laser drive circuits, and a data acquisition circuit. The optical and electrical parts and the gas circuit were integrated into a portable carrying case (height = 134 mm, length = 388 mm, and width = 290 mm). A TDLAS drive module (size: 90 mm × 45 mm) was designed to realize the function of laser current and temperature control with a temperature control accuracy of ±1.4 mK and a current control accuracy of ±0.5 μA, and signal acquisition and demodulation. The weight and power consumption of the TDLAS system were only 5 kg and 10 W, respectively. Distributed feedback lasers (2004 nm and 1392 nm) were employed to target CO2 and H2O absorption lines, respectively. According to Allan analysis, the detection limits of CO2 and H2O were 0.13 ppm and 3.7 ppm at an average time of 18 s and 35 s, respectively. The system response time was approximately 10 s. Sensor performance was verified by measuring atmospheric CO2 and H2O concentrations for 240 h. Experimental results were compared with those obtained using a commercial instrument LI-7500, which uses non-dispersive infrared technology. Measurements of the developed gas analyzer were in good agreement with those of the commercial instrument, and its accuracy was comparable. Therefore, the TDLAS sensor has strong application prospects in atmospheric CO2 and H2O concentration detection and ecological soil flux monitoring.

show abstract

Multi-Gas Detection System Based on Non-Dispersive Infrared (NDIR) Spectral Technology

Cited by 31 publications

References 27 publications

Miniaturized CO₂ Gas Sensor Using 20% ScAlN-Based Pyroelectric Detector

Miniaturized CO₂ Gas Sensor Using 20% ScAlN-Based Pyroelectric Detector

On-Site Detection of Volatile Organic Compounds (VOCs)

Portable TDLAS Sensor for Online Monitoring of CO2 and H2O Using a Miniaturized Multi-Pass Cell

Contact Info

Product

Resources

About

Multi-Gas Detection System Based on Non-Dispersive Infrared (NDIR) Spectral Technology

Cited by 31 publications

References 27 publications

Miniaturized CO2 Gas Sensor Using 20% ScAlN-Based Pyroelectric Detector

Miniaturized CO2 Gas Sensor Using 20% ScAlN-Based Pyroelectric Detector

On-Site Detection of Volatile Organic Compounds (VOCs)

Portable TDLAS Sensor for Online Monitoring of CO2 and H2O Using a Miniaturized Multi-Pass Cell

Contact Info

Product

Resources

About

Miniaturized CO₂ Gas Sensor Using 20% ScAlN-Based Pyroelectric Detector

Miniaturized CO₂ Gas Sensor Using 20% ScAlN-Based Pyroelectric Detector