Submit to Chemosensors Review for Chemosensors Propose a Special Issue

Journal Menu

Journal Browser

Gas Sensors for Monitoring Environmental Changes

Print Special Issue Flyer
Special Issue Editors
Special Issue Information
Keywords
Related Special Issue
Published Papers

A special issue of Chemosensors (ISSN 2227-9040). This special issue belongs to the section "Applied Chemical Sensors".

Deadline for manuscript submissions: closed (30 August 2023) | Viewed by 21189

Share This Special Issue

Special Issue Editors

Dr. Kai Xu

E-Mail Website
Guest Editor

School of Engineering, RMIT University, Melbourne, VIC 3000, Australia
Interests: low-dimensional materials; gas sensing; optoelectronic devices; micro–nano fabrications
Special Issues, Collections and Topics in MDPI journals

Dr. Zhong Li

E-Mail Website
Guest Editor

Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, China
Interests: nanomaterials; 2D materials and heterostructures; functional materials; gas sensor; microwave absorption
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Global warming and climate change have become serious environmental threats in the last decade. Air pollution due to the rapid development of modernization and urbanization is the major cause of environmental deterioration. The emission of sulfur dioxide (SO₂) and nitrogen oxides (NOx), for instance, can be directly linked to the evolution of acid rain. Greenhouse gases, including carbon dioxide (CO₂), methane (CH₄), and NOx, are the main driver of global warming. Thus, the continuous monitoring and control of such pollutants are imperative to prevent environmental disasters.

This fact has prompted efforts to find new and user-friendly techniques for the detection of gases hazardous to the environment and human health, which has led to the development of key technologies for the rapid, selective, sensitive, and efficient detection of gases, chemical vapors, and explosives. Given the boom of the Internet of Things (IoT), the next generation of gas sensors is expected to be massively deployed into dense network systems with low cost, low power consumption, and long-term stability. In addition, to achieve continuous monitoring, gas sensors may also need to demonstrate a high tolerance to environmental variables such as temperature, humidity, and pressure.

This Special Issue aims to provide a comprehensive collection of the latest advances in gas sensors based on various materials and outlook for the gas sensors in environmental monitoring. We cordially invite you to submit an article to this Special Issue. We welcome short communications, full research articles, and timely reviews focusing on advanced gas sensing techniques.

Dr. Kai Xu
Dr. Zhong Li
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Chemosensors is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

gas sensors
environmental monitoring
nanomaterial
metal oxides
metal sulfides
pollutants
semiconductor

Related Special Issue

Gas Sensors for Monitoring Environmental Changes, 2nd Edition in Chemosensors (5 articles)

Published Papers (12 papers)

Download All Papers

Research

12 pages, 5032 KiB

Open AccessArticle

Preparation and Hydrogen-Sensitive Property of WO₃/Graphene/Pd Ternary Composite

by Lin Wang, Fei An, Xinmei Liu, Dongzhi Zhang and Zhe Yang

Chemosensors 2023, 11(7), 410; https://doi.org/10.3390/chemosensors11070410 - 21 Jul 2023

Cited by 1 | Viewed by 1100

Abstract

Hydrogen (H₂) is a renewable energy source that has the potential to reduce greenhouse gas emissions. However, H₂ is also highly flammable and explosive, requiring sensitive and safe sensors for its detection. This work presents the synthesis and characterization of WO₃/graphene binary and WO₃/graphene/Pd (WG-Pd) ternary nanocomposites with varying graphene and Pd contents using the microwave-assisted hydrothermal method. The excellent catalytic efficacy of Pd nanoparticles facilitated the disintegration of hydrogen molecules into hydrogen atoms with heightened activity, consequently improving the gas-sensing properties of the material. Furthermore, the incorporation of graphene, possessing high conductivity, serves to augment the mobility of charge carriers within the ternary materials, thereby expediting the response/recovery rates of gas sensors. Both graphene and Pd nanoparticles, with work functions distinct from WO₃, engender the formation of a heterojunction at the interface of these diverse materials. This enhances the efficacy of electron–hole pair separation and further amplifies the gas-sensing performance of the ternary materials. Consequently, the WG-Pd based sensors exhibited the best gas-sensing performance when compared to anther materials, such as a wide range of hydrogen concentrations (0.05–4 vol.%), a short response time and a good selectivity below 100 °C, even at room temperature. This result indicates that WG-Pd ternary materials are a promising room-temperature hydrogen-sensing materials for H₂ detection. Full article

(This article belongs to the Special Issue Gas Sensors for Monitoring Environmental Changes)

► Show Figures

Figure 1

15 pages, 2209 KiB

Open AccessArticle

The Human Nose as a Chemical Sensor in the Perception of Coffee Aroma: Individual Variability

by Roberto Crnjar, Paolo Solari and Giorgia Sollai

Chemosensors 2023, 11(4), 248; https://doi.org/10.3390/chemosensors11040248 - 17 Apr 2023

Cited by 2 | Viewed by 1601

Abstract

The flavor of foods and beverages is generally composed of a mixture of volatile compounds, however not all the molecules that form an aroma are sensorially relevant. The odor-active compounds present in a mixture are different for each subject, both in quantitative and qualitative terms. This means that the ability of the human nose to act as a chemical sensor varies among individuals. In this study, we used the headspace of roasted coffee beans as a complex olfactory stimulus and, by means of the coupled Gas Chromatography-Olfactometry (GC-O) technique, the single components of coffee flavor were separated. Each subject, previously classified for his/her olfactory status (normosmic, hyposmic or anosmic) by means of the Sniffin’ Sticks battery (composed of Threshold, Discrimination and Identification subtests), had to identify and evaluate each smelled molecule. The results show that the individual ability to detect individual compounds during the GC-O experiments and the odor intensity reported during the sniffing of pen #10 (the pen of the identification test) containing coffee aroma were related to TDI olfactory status (based on the score obtained from the sum composed of Threshold, Discrimination and Identification scores). We also found that the number of total molecules and of molecules smelling of coffee is linearly related to the TDI olfactory score. Finally, the odor intensity reported when sniffing pen #10 containing coffee aroma is positively correlated with the number of molecules detected and the average intensity reported. In conclusion, our findings show that the human perception of both individual compounds and complex odors is strongly conditioned by the olfactory function of subjects. Full article

(This article belongs to the Special Issue Gas Sensors for Monitoring Environmental Changes)

► Show Figures

Figure 1

15 pages, 5615 KiB

Open AccessArticle

Chemoresistive Properties of V₂CT_x MXene and the V₂CT_x/V₃O₇ Nanocomposite Based on It

by Artem S. Mokrushin, Ilya A. Nagornov, Aleksey A. Averin, Tatiana L. Simonenko, Nikolay P. Simonenko, Elizaveta P. Simonenko and Nikolay T. Kuznetsov

Chemosensors 2023, 11(2), 142; https://doi.org/10.3390/chemosensors11020142 - 15 Feb 2023

Cited by 8 | Viewed by 2041 | Correction

Abstract

The in-situ Raman spectroscopy oxidation of the accordion-like V₂CT_x MXene has been studied. It was found that a nanocomposite of V₂CT_x/V₃O₇ composition was formed as a result. The elemental and phase composition, the microstructure of the synthesized V₂CT_x powder and MXene film as well as the V₂CT_x/V₃O₇ nanocomposite obtained at a minimum oxidation temperature of 250 °C were studied using a variety of physical and chemical analysis methods. It was found that the obtained V₂CT_x and V₂CT_x/V₃O₇ films have an increased sensitivity to ammonia and nitrogen dioxide, respectively, at room temperature and zero humidity. It was shown that the V₂CT_x/V₃O₇ composite material is characterized by an increase in the response value for a number of analytes (including humidity) by more than one order of magnitude, as well as a change in their detection mechanisms compared to the individual V₂CT_x MXene. Full article

(This article belongs to the Special Issue Gas Sensors for Monitoring Environmental Changes)

► Show Figures

Figure 1

20 pages, 8504 KiB

Open AccessArticle

Humidity and Temperature Sensing of Mixed Nickel–Magnesium Spinel Ferrites

by Milena P. Dojcinovic, Zorka Z. Vasiljevic, Lazar Rakocevic, Vera P. Pavlovic, Souad Ammar-Merah, Jelena D. Vujancevic and Maria Vesna Nikolic

Chemosensors 2023, 11(1), 34; https://doi.org/10.3390/chemosensors11010034 - 2 Jan 2023

Cited by 3 | Viewed by 1702

Abstract

Temperature- and humidity-sensing properties were evaluated of Ni_xMg_1-x spinel ferrites (0 ≤ x ≤ 1) synthesized by a sol-gel combustion method using citric acid as fuel and nitrate ions as oxidizing agents. After the exothermic reaction, amorphous powders were calcined at 700 °C followed by characterization with XRD, FTIR, XPS, EDS and Raman spectroscopy and FESEM microscopy. Synthesized powders were tested as humidity- and temperature-sensing materials in the form of thick films on interdigitated electrodes on alumina substrate in a climatic chamber. The physicochemical investigation of synthesized materials revealed a cubic spinel

F d \bar{3} m

phase, nanosized but agglomerated particles with a partially to completely inverse spinel structure with increasing Ni content. Ni_0.1Mg_0.9Fe₂O₄ showed the highest material constant (B_30,90) value of 3747 K and temperature sensitivity (α) of −4.08%/K compared to pure magnesium ferrite (B_30,90 value of 3426 K and α of −3.73%/K) and the highest average sensitivity towards humidity of 922 kΩ/%RH in the relative humidity (RH) range of 40–90% at the working temperature of 25 °C. Full article

(This article belongs to the Special Issue Gas Sensors for Monitoring Environmental Changes)

► Show Figures

Figure 1

12 pages, 2423 KiB

Open AccessArticle

Hydrogen Sensors Based on In₂O₃ Thin Films with Bimetallic Pt/Pd Catalysts on the Surface and Tin and Dysprosium Impurities in the Bulk

by Nadezhda Maksimova, Tatyana Malinovskaya, Valentina Zhek, Nadezhda Sergeychenko, Evgenii Chernikov, Ivan Lapin and Valery Svetlichnyi

Chemosensors 2023, 11(1), 23; https://doi.org/10.3390/chemosensors11010023 - 27 Dec 2022

Cited by 1 | Viewed by 1354

Abstract

This paper presents the results of studying the characteristics of hydrogen sensors based on thin In₂O₃ films modified with tin and dysprosium with dispersed double Pt/Pd catalysts deposited on the surface. To control the content of Sn and Dy in the films, an original technology was developed, and ceramic targets were fabricated from powders of the In–Dy–O, Dy–Sn–O, and In–Dy–Sn–O systems synthesized by the sol–gel method. Films of complex composition were obtained by RF magnetron sputtering of the corresponding targets. Structural features of the obtained thin films were studied by Raman spectroscopy. It is shown that various combinations of tin and dysprosium concentrations, as well as the presence of Pt/Pd catalysts on the surface, have a significant effect on the defectiveness of the films and the density of oxygen adsorption centers. As a result, the resistance of sensors in pure air (R₀), the activation energies of the temperature dependences of R₀, the bending of the energy bands at the grain boundaries of the semiconductor, and the responses to the action of hydrogen in the concentration range of 20–25,000 ppm change. A unique feature of Pt/Pd/ In₂O₃: Sn (0.5 at%), Dy (4.95 at%) films is their high sensitivity at 20–100 ppm and the absence of signal saturation in the region of high hydrogen concentrations of 5000–25,000 ppm, allowing them to be used to detect H₂ in a wide range of concentrations. Full article

(This article belongs to the Special Issue Gas Sensors for Monitoring Environmental Changes)

► Show Figures

Figure 1

17 pages, 5684 KiB

Open AccessArticle

Effect of Ti₂CT_x MXene Oxidation on Its Gas-Sensitive Properties

by Artem S. Mokrushin, Ilya A. Nagornov, Philipp Yu. Gorobtsov, Aleksey A. Averin, Tatiana L. Simonenko, Nikolay P. Simonenko, Elizaveta P. Simonenko and Nikolay T. Kuznetsov

Chemosensors 2023, 11(1), 13; https://doi.org/10.3390/chemosensors11010013 - 22 Dec 2022

Cited by 9 | Viewed by 2247

Abstract

The oxidation process was studied for the synthesized low-layer Ti₂CT_x MXene deposited on a special Al₂O₃/Pt sensor substrate using in situ Raman spectroscopy. It is noted that on the ceramic parts of the substrate (Al₂O₃), the beginning of oxidation (appearance of anatase mod phase) is observed already at 316 °C, in comparison with platinum, for which the appearance of anatase is noted only at 372 °C. At the temperature 447 °C, the initial MXene film is completely oxidized to TiO₂. Using scanning electron microscopy and atomic force microscopy, the microstructure and dispersity of the obtained MXene film were studied. It was found that the obtained films exhibit chemoresistive responses to the detection of a wide group of gases, H₂, CO, NH₃, C₆H₆, C₃H₆O, CH₄, C₂H₅OH and O₂, at room temperature and RH = 50%. The highest sensitivity is observed for NH₃. The partial oxidation of the Ti₂CT_x MXene was shown to favorably affect the gas-sensitive properties. Full article

(This article belongs to the Special Issue Gas Sensors for Monitoring Environmental Changes)

► Show Figures

Figure 1

20 pages, 4582 KiB

Open AccessArticle

Tetrafluorosubstituted Metal Phthalocyanines: Study of the Effect of the Position of Fluorine Substituents on the Chemiresistive Sensor Response to Ammonia

by Darya Klyamer, Dmitry Bonegardt, Pavel Krasnov, Alexander Sukhikh, Pavel Popovetskiy and Tamara Basova

Chemosensors 2022, 10(12), 515; https://doi.org/10.3390/chemosensors10120515 - 4 Dec 2022

Cited by 5 | Viewed by 1459

Abstract

A comparative analysis of the chemiresistive sensor response of thin films of a series of tetrasubstituted phthalocyanines of various metals with F-substituent in peripheral (MPcF₄-p, M = Cu, Co, Zn, Pb, VO) and non-peripheral (MPcF₄-np) positions in macroring to low concentrations of ammonia (1–50 ppm) was carried out. It was found that MPcF₄-p films exhibit a higher sensor response than MPcF₄-np ones. A CoPcF₄-p film demonstrated a calculated LOD of 0.01 ppm with a recovery time of 215 s, while a VOPcF₄-p film had LOD of 0.04 ppm and the recovery time of 270 s. The selectivity test showed that CO₂, ethanol, acetone, benzene, and formaldehyde did not interfere with the determination of ammonia, while H₂S at a concentration of more than 10 ppm could act as an interfering gas. It was shown that, as a result of quantum-chemical calculations, the observed regularities are best described by the interaction of NH₃ with phthalocyanines through the formation of hydrogen bonds between NH₃ and side atoms of the macroring. In the case of MPcF₄-p, the NH₃ molecule approaches the macrocycle more closely and binds more strongly than in the case of MPcF₄-np. The stronger binding leads to a stronger effect of the ammonia molecule on the electronic structure of phthalocyanine and, as a consequence, on the chemiresistive sensor response of the films to ammonia. Full article

(This article belongs to the Special Issue Gas Sensors for Monitoring Environmental Changes)

► Show Figures

Figure 1

11 pages, 3017 KiB

Open AccessArticle

Prediction of Diamene-Based Chemosensors

by Danil W. Boukhvalov and Vladimir Yu. Osipov

Chemosensors 2022, 10(11), 480; https://doi.org/10.3390/chemosensors10110480 - 15 Nov 2022

Cited by 4 | Viewed by 1614

Abstract

This paper presents the results of systematic studies of the atomic structure of the layered bulk, bilayer, and monolayer of diamene (a two-dimensional diamond monolayer recently synthesized by various methods) functionalized with fluorine and hydroxyl groups with the chemical formulas C₂F and C₂OH. The results of our calculations show that both types of diamene under discussion have a wide optical gap corresponding to the absorption of light in the UV spectral range. The formation of a boundary between these two types of diamene layers leads to a significant decrease in the band gap. Therefore, this layered material, with an interface between fluorinated and hydroxylated diamenes (C₂F/C₂OH structures), can be considered a suitable material for converting UV radiation into visible light in the orange-yellow part of the spectrum. The adsorption of acetone or water on the C₂F/C₂OH structures results in visible changes in the band gap. The effect on photoemission is different for different detected analytes. The presence of formaldehyde in water ensures the appearance of distinct peaks in the absorption spectra of structures based on C₂F/C₂OH. Our simulation results suggest that the simulated C₂F/C₂OH structures can be used as chemically stable, lightweight materials composed of common elements for a highly selective chemical sensor in liquid and air. Full article

(This article belongs to the Special Issue Gas Sensors for Monitoring Environmental Changes)

► Show Figures

Figure 1

16 pages, 2965 KiB

Open AccessArticle

Energy-Efficient Chemiresistive Sensor Array Based on SWCNT Networks, WO₃ Nanochannels and SWCNT-Pt Heterojunctions for NH₃ Detection against the Background Humidity

by Alexey V. Romashkin, Andrey V. Lashkov, Victor V. Sysoev, Nikolay S. Struchkov, Evgeny V. Alexandrov and Denis D. Levin

Chemosensors 2022, 10(11), 476; https://doi.org/10.3390/chemosensors10110476 - 12 Nov 2022

Viewed by 1409

Abstract

Recently, promising results have been achieved in improving the sensitivity to ammonia in gas sensors through the use of structures composed of heterojunctions or nanochannels. However, their sensitivity is highly dependent on the background humidity under air conditions. The sensor structures which could ensure selective ammonia detection with a low detection limit, despite interference from changing background humidity, remain highly demanded. In this work, we consider sensing units containing (i) nanochannels formed by a continuous tungsten oxide nanolayer to appear in contact between single-walled carbon nanotubes (SWCNTs) and a Pt sublayer and (ii) SWCNT-Pt junctions in frames of mass-scale microelectronic technologies. SWCNTs were deposited by spray-coating on a thin WO₃/Pt/W sublayer formed by a photolithographic pattern to be accompanied by satellite samples with just SWCNTs for reference purposes. We elucidate the specific differences that appeared in the response of sensors based on SWCNT-Pt junctions and WO₃ nanochannels relative to satellite SWCNT samples with a similar SWCNT network density. Particularly, while a similar response to NH₃ vapors mixed with dry air is observed for each sensor type, the response to NH₃ is reduced significantly in the presence of background humidity, of 45 rel.%, especially in the case of WO₃ nanochannel structures even at room temperature. A multisensor array based on the four various sensing structures involving SWCNT-Pt junctions, WO₃ nanochannels, and their satellite-only-SWCNT ones allowed us to determine a correct ammonia concentration via utilizing the linear discriminant analysis despite the presence of background air humidity. Thus, such an energy-efficient multisensor system can be used for environmental monitoring of ammonia content, health monitoring, and other applications. Full article

(This article belongs to the Special Issue Gas Sensors for Monitoring Environmental Changes)

► Show Figures

Graphical abstract

13 pages, 7323 KiB

Open AccessArticle

Gas Sensors Based on Exfoliated g-C₃N₄ for CO₂ Detection

by Ahmed Kotbi, Manal Benyoussef, El Mostafa Ressami, Michael Lejeune, Brahim Lakssir and Mustapha Jouiad

Chemosensors 2022, 10(11), 470; https://doi.org/10.3390/chemosensors10110470 - 10 Nov 2022

Cited by 7 | Viewed by 2004

Abstract

We report on the investigation of graphitic carbon nitride (g-C₃N₄) for carbon dioxide (CO₂) sensor applications. g-C₃N₄ is prepared by the thermal polycondensation of thiourea and sprayed onto a substrate with interdigitated electrodes. The resulting sensor device exhibited a high sensitivity to CO₂ molecules of ~200 ppm, a high responsivity of ~730 ms at 40 °C and a full recovery time of 36 s. Furthermore, a set of various characterization measurements demonstrated the excellent stability of both the g-C₃N₄ nanosheets and the fabricated gas sensor device. Meanwhile, density functional theory (DFT) calculations for the bulk and monolayer models, based on tri-s-triazine, revealed the optoelectronic properties of g-C₃N₄ and the interaction energy with CO₂, which is evaluated at −0.59 eV. This value indicates the very good affinity of g-C₃N₄ nanosheets to CO₂ molecules. Our findings shed light on the potential for g-C₃N₄ to be used for the development of high-performing gas sensor devices. Full article

(This article belongs to the Special Issue Gas Sensors for Monitoring Environmental Changes)

► Show Figures

Graphical abstract

12 pages, 2999 KiB

Open AccessArticle

Photoactivated In₂O₃-GaN Gas Sensors for Monitoring NO₂ with High Sensitivity and Ultralow Operating Power at Room Temperature

by Jafetra Rambeloson, Dimitris E. Ioannou, Parameswari Raju, Xiao Wang, Abhishek Motayed, Hyeong Jin Yun and Qiliang Li

Chemosensors 2022, 10(10), 405; https://doi.org/10.3390/chemosensors10100405 - 9 Oct 2022

Viewed by 1774

Abstract

Photoactivated gallium nitride (GaN) nanowire-based gas sensors, functionalized with either bare In₂O₃ or In₂O₃ coated with a nanolayer of evaporated Au (Au/In₂O₃), were designed and fabricated for high-sensitivity sensing of NO₂ and low-power operation. The sensors were tested at room temperature under 265 nm and 365 nm ultraviolet illumination at several power levels and in relative humidity ranging from over 20% to 80%. Under all conditions, photoconductivity was lower in the Au/In₂O₃-functionalized sensors compared to that of sensors functionalized with bare In₂O₃. However, when tested in the presence of NO₂, the Au/In₂O₃ sensors consistently outperformed In₂O₃ sensors, the measured sensitivity being greater at 265 nm compared to 365 nm. The results show significant power reduction (×12) when photoactivating at (265 nm, 5 mW) compared to (365 nm, 60 mW). Maximum sensitivities of 27% and 42% were demonstrated with the Au/In₂O₃ sensors under illumination at (265 nm, 5 mW) for 1 ppm and 10 ppm concentration, respectively. Full article

(This article belongs to the Special Issue Gas Sensors for Monitoring Environmental Changes)

► Show Figures

Figure 1

12 pages, 3910 KiB

Open AccessArticle

Simultaneous Detection of CO₂ and CH₄ Using a DFB Diode Laser-Based Absorption Spectrometer

by Xu Wu, Yulong Du, Shijian Shi, Cong Jiang, Xueliang Deng, Song Zhu, Xiaolong Jin and Jingsong Li

Chemosensors 2022, 10(10), 390; https://doi.org/10.3390/chemosensors10100390 - 24 Sep 2022

Viewed by 1941

Abstract

In this paper, an attractive gas sensing technique based on fiber optical sensing ideal was developed for the detection of multi-gas species simultaneously. Calibration-free laser absorption spectroscopy (LAS) was used and combined with a multi-pass optical absorption cell, two fiber-coupled near-infrared (NIR) distributed feedback (DFB) diode lasers are used and coupled into a single optical path for measuring CO₂ and CH₄ absorption spectra simultaneously. The optimal sampling pressure, laser tuning characteristics, spectral sampling points, and potential optical interference are theoretically and experimentally investigated in detail. The results indicated that the proposed technique has good reliability and has been successfully demonstrated for ambient CO₂ and CH₄ detection by using a single sample cell and detector. An Allan–Werle deviation analysis shows that detection limits of 0.12 ppm for CH₄ and 35.97 ppm for CO₂ can be obtained with an integration time of 181 s and 166 s, respectively. The proposed technique can be expanded to measure more molecules simultaneously by combing laser array and may pave a new way for developing a low-cost and ultra-compact multi-gas laser spectroscopy sensing system. Full article

(This article belongs to the Special Issue Gas Sensors for Monitoring Environmental Changes)

► Show Figures