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Detection of Contaminants in Hydrogen Fuel for Fuel Cell Electrical Vehicles with Sensors—Available Technology, Testing Protocols and Implementation Challenges. Processes (Basel) 2021. [DOI: 10.3390/pr10010020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Europe’s low-carbon energy policy favors a greater use of fuel cells and technologies based on hydrogen used as a fuel. Hydrogen delivered at the hydrogen refueling station must be compliant with requirements stated in different standards. Currently, the quality control process is performed by offline analysis of the hydrogen fuel. It is, however, beneficial to continuously monitor at least some of the contaminants onsite using chemical sensors. For hydrogen quality control with regard to contaminants, high sensitivity, integration parameters, and low cost are the most important requirements. In this study, we have reviewed the existing sensor technologies to detect contaminants in hydrogen, then discussed the implementation of sensors at a hydrogen refueling stations, described the state-of-art in protocols to perform assessment of these sensor technologies, and, finally, identified the gaps and needs in these areas. It was clear that sensors are not yet commercially available for all gaseous contaminants mentioned in ISO14687:2019. The development of standardized testing protocols is required to go hand in hand with the development of chemical sensors for this application following a similar approach to the one undertaken for air sensors.
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Readout Integrated Circuit for Small-Sized and Low-Power Gas Sensor Based on HEMT Device. SENSORS 2021; 21:s21165637. [PMID: 34451080 PMCID: PMC8402593 DOI: 10.3390/s21165637] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 08/12/2021] [Accepted: 08/19/2021] [Indexed: 01/06/2023]
Abstract
This paper presents a small-sized, low-power gas sensor system combining a high-electron-mobility transistor (HEMT) device and readout integrated circuit (ROIC). Using a semiconductor-based HEMT as a gas-sensing device, it is possible to secure high sensitivity, reduced complexity, low power, and small size of the ROIC sensor system. Unlike existing gas sensors comprising only HEMT elements, the proposed sensor system has both an ROIC and a digital controller and can control sensor operation through a simple calibration process with digital signal processing while maintaining constant performance despite variations. The ROIC mainly consists of a transimpedance amplifier (TIA), a negative-voltage generator, and an analog-to-digital converter (ADC) and is designed to match a minimum target detection unit of 1 ppm for hydrogen. The prototype ROIC for the HEMT presented herein was implemented in a 0.18 µm complementary metal–oxide–semiconductor (CMOS) process. The total measured power consumption and detection unit of the proposed ROIC for hydrogen gas were 3.1 mW and 2.6 ppm, respectively.
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Lee S, Nam K, Kim JH, Hong GY, Kim SD. Effects of Seed-Layer N 2O Plasma Treatment on ZnO Nanorod Based Ultraviolet Photodetectors: Experimental Investigation with Two Different Device Structures. NANOMATERIALS 2021; 11:nano11082011. [PMID: 34443842 PMCID: PMC8398532 DOI: 10.3390/nano11082011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 07/30/2021] [Accepted: 08/03/2021] [Indexed: 11/16/2022]
Abstract
The crystalline quality of ZnO NR (nanorod) as a sensing material for visible blind ultraviolet PDs (photodetectors) critically depends on the SL (seed layer) material of properties, which is a key to high-quality nanocrystallite growth, more so than the synthesis method. In this study, we fabricated two different device structures of a gateless AlGaN/GaN HEMT (high electron mobility transistor) and a photoconductive PD structure with an IDE (interdigitated electrode) pattern implemented on a PET (polyethylene terephthalate) flexible substrate, and investigated the impact on device performance through the SL N2O plasma treatment. In case of HEMT-based PD, the highest current on-off ratio (~7) and spectral responsivity R (~1.5 × 105 A/W) were obtained from the treatment for 6 min, whereas the IDE pattern-based PD showed the best performance (on-off ratio = ~44, R = ~69 A/W) from the treatment for 3 min and above, during which a significant etch damage on PET substrates was produced. This improvement in device performance was due to the enhancement in NR crystalline quality as revealed by our X-ray diffraction, photoluminescence, and microanalysis.
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Nguyen VC, Kim K, Kim H. Performance Optimization of Nitrogen Dioxide Gas Sensor Based on Pd-AlGaN/GaN HEMTs by Gate Bias Modulation. MICROMACHINES 2021; 12:mi12040400. [PMID: 33916387 PMCID: PMC8066909 DOI: 10.3390/mi12040400] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 03/31/2021] [Accepted: 04/02/2021] [Indexed: 11/16/2022]
Abstract
We investigated the sensing characteristics of NO2 gas sensors based on Pd-AlGaN/GaN high electron mobility transistors (HEMTs) at high temperatures. In this paper, we demonstrated the optimization of the sensing performance by the gate bias, which exhibited the advantage of the FET-type sensors compared to the diode-type ones. When the sensor was biased near the threshold voltage, the electron density in the channel showed a relatively larger change with a response to the gas exposure and demonstrated a significant improvement in the sensitivity. At 300 °C under 100 ppm concentration, the sensor’s sensitivities were 26.7% and 91.6%, while the response times were 32 and 9 s at VG = 0 V and VG = −1 V, respectively. The sensor demonstrated the stable repeatability regardless of the gate voltage at a high temperature.
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Affiliation(s)
- Van Cuong Nguyen
- School of Electronic and Electrical Engineering, Hongik University, Seoul 04066, Korea;
| | - Kwangeun Kim
- School of Electronics and Information Engineering, Korea Aerospace University, Gyeonggi 10540, Korea;
| | - Hyungtak Kim
- School of Electronic and Electrical Engineering, Hongik University, Seoul 04066, Korea;
- Correspondence: ; Tel.: +82-2-320-3013
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Overview of Power Electronic Switches: A Summary of the Past, State-of-the-Art and Illumination of the Future. MICROMACHINES 2020; 11:mi11121116. [PMID: 33339322 PMCID: PMC7767217 DOI: 10.3390/mi11121116] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 12/02/2020] [Accepted: 12/12/2020] [Indexed: 11/16/2022]
Abstract
As the need for green and effective utilization of energy continues to grow, the advancements in the energy and power electronics industry are constantly driven by this need, as both industries are intertwined for obvious reasons. The developments in the power electronics industry has over the years hinged on the progress of the semiconductor device industry. The semiconductor device industry could be said to be on the edge of a turn into a new era, a paradigm shift from the conventional silicon devices to the wide band gap semiconductor technologies. While a lot of work is being done in research and manufacturing sectors, it is important to look back at the past, evaluate the current progress and look at the prospects of the future of this industry. This paper is unique at this time because it seeks to give a good summary of the past, the state-of-the-art, and highlight the opportunities for future improvements. A more or less 'forgotten' power electronic switch, the four-quadrant switch, is highlighted as an opportunity waiting to be exploited as this switch presents a potential for achieving an ideal switch. Figures of merit for comparing semiconductor materials and devices are also presented in this review.
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Hydrogen Sensing Performance of ZnO Schottky Diodes in Humid Ambient Conditions with PMMA Membrane Layer. SENSORS 2020; 20:s20030835. [PMID: 32033189 PMCID: PMC7038668 DOI: 10.3390/s20030835] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 01/31/2020] [Accepted: 01/31/2020] [Indexed: 12/04/2022]
Abstract
Enhanced hydrogen sensing performance of Pt Schottky diodes on ZnO single crystal wafers in humid ambient conditions is reported using a polymethylmethacrylate (PMMA) membrane layer. ZnO diode sensors showed little change in forward current when switching to wet ambient H2 conditions with 100% relative humidity. This sensitivity drop in the presence of water vapor can be attributed to surface coverage of hydroxyl groups on the Pt surface in humid ambient conditions. The hydrogen sensitivity of PMMA-coated diode sensors recovered up to 805% in wet H2 ambient conditions at room temperature. The PMMA layer can selectively filter water vapor and allow H2 molecules to pass through the membrane layer. It is clear that the PMMA layer can effectively serve as a moisture barrier because of low water vapor permeability and its hydrophobicity. In both dry and wet conditions, ZnO diodes exhibited relatively fast and stable on/off switching in each cycle with good repeatability.
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7
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Zhang M, Zhao C, Gong H, Niu G, Wang F. Porous GaN Submicron Rods for Gas Sensor with High Sensitivity and Excellent Stability at High Temperature. ACS APPLIED MATERIALS & INTERFACES 2019; 11:33124-33131. [PMID: 31424185 DOI: 10.1021/acsami.9b09769] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Highly porous GaN submicron rods have been synthesized successfully by a facile hydrothermal method and heat treatment under controlled atmosphere. The morphology and size of the hydrothermal products are tailorable by adjusting the concentration of precursor solutions. Upon calcination in air, the nanorod-assembled GaOOH submicron rods are converted into bundlelike Ga2O3 and into porous GaN submicron rods under an ammonia flow. Gas-sensing characterization demonstrates that the sensors based on porous GaN exhibit high sensitivity and fast response to ethanol vapor, as well as excellent stability and reliability at high temperature. The highly porous GaN submicron rods with a large specific surface area, small grain size, and high length-to-diameter ratio show better response to ethanol. A possible sensing enhancement mechanism is also proposed. This study provides a promising route for the novel synthesis of GaN submicron rods for high-performance gas sensors.
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8
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Khan MAH, Rao MV, Li Q. Recent Advances in Electrochemical Sensors for Detecting Toxic Gases: NO₂, SO₂ and H₂S. SENSORS (BASEL, SWITZERLAND) 2019; 19:E905. [PMID: 30795591 PMCID: PMC6413198 DOI: 10.3390/s19040905] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Revised: 02/11/2019] [Accepted: 02/14/2019] [Indexed: 01/04/2023]
Abstract
Toxic gases, such as NOx, SOx, H₂S and other S-containing gases, cause numerous harmful effects on human health even at very low gas concentrations. Reliable detection of various gases in low concentration is mandatory in the fields such as industrial plants, environmental monitoring, air quality assurance, automotive technologies and so on. In this paper, the recent advances in electrochemical sensors for toxic gas detections were reviewed and summarized with a focus on NO₂, SO₂ and H₂S gas sensors. The recent progress of the detection of each of these toxic gases was categorized by the highly explored sensing materials over the past few decades. The important sensing performance parameters like sensitivity/response, response and recovery times at certain gas concentration and operating temperature for different sensor materials and structures have been summarized and tabulated to provide a thorough performance comparison. A novel metric, sensitivity per ppm/response time ratio has been calculated for each sensor in order to compare the overall sensing performance on the same reference. It is found that hybrid materials-based sensors exhibit the highest average ratio for NO₂ gas sensing, whereas GaN and metal-oxide based sensors possess the highest ratio for SO₂ and H₂S gas sensing, respectively. Recently, significant research efforts have been made exploring new sensor materials, such as graphene and its derivatives, transition metal dichalcogenides (TMDs), GaN, metal-metal oxide nanostructures, solid electrolytes and organic materials to detect the above-mentioned toxic gases. In addition, the contemporary progress in SO₂ gas sensors based on zeolite and paper and H₂S gas sensors based on colorimetric and metal-organic framework (MOF) structures have also been reviewed. Finally, this work reviewed the recent first principle studies on the interaction between gas molecules and novel promising materials like arsenene, borophene, blue phosphorene, GeSe monolayer and germanene. The goal is to understand the surface interaction mechanism.
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Affiliation(s)
- Md Ashfaque Hossain Khan
- Department of Electrical and Computer Engineering, George Mason University, Fairfax, VA 22030, USA.
| | - Mulpuri V Rao
- Department of Electrical and Computer Engineering, George Mason University, Fairfax, VA 22030, USA.
| | - Qiliang Li
- Department of Electrical and Computer Engineering, George Mason University, Fairfax, VA 22030, USA.
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9
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Evaluation and Selection of Materials for Particulate Matter MEMS Sensors by Using Hybrid MCDM Methods. SUSTAINABILITY 2018. [DOI: 10.3390/su10103451] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Air pollution poses serious problems as global industrialization continues to thrive. Since air pollution has grave impacts on human health, industry experts are starting to fathom how to integrate particulate matter (PM) sensors into portable devices; however, traditional micro-electro-mechanical systems (MEMS) gas sensors are too large. To overcome this challenge, experts from industry and academia have recently begun to investigate replacing the traditional etching techniques used on MEMS with semiconductor-based manufacturing processes and materials, such as gallium nitride (GaN), gallium arsenide (GaAs), and silicon. However, studies showing how to systematically evaluate and select suitable materials are rare in the literature. Therefore, this study aims to propose an analytic framework based on multiple criteria decision making (MCDM) to evaluate and select the most suitable materials for fabricating PM sensors. An empirical study based on recent research was conducted to demonstrate the feasibility of our analytic framework. The results provide an invaluable future reference for research institutes and providers.
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10
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High Sensitive pH Sensor Based on AlInN/GaN Heterostructure Transistor. SENSORS 2018; 18:s18051314. [PMID: 29695112 PMCID: PMC5982566 DOI: 10.3390/s18051314] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Revised: 04/12/2018] [Accepted: 04/21/2018] [Indexed: 12/02/2022]
Abstract
The AlInN/GaN high-electron-mobility-transistor (HEMT) indicates better performances compared with the traditional AlGaN/GaN HEMTs. The present work investigated the pH sensor functionality of an analogous HEMT AlInN/GaN device with an open gate. It was shown that the Al0.83In0.17N/GaN device demonstrates excellent pH sense functionality in aqueous solutions, exhibiting higher sensitivity (−30.83 μA/pH for AlInN/GaN and −4.6 μA/pH for AlGaN/GaN) and a faster response time, lower degradation and good stability with respect to the AlGaN/GaN device, which is attributed to higher two-dimensional electron gas (2DEG) density and a thinner barrier layer in Al0.83In0.17N/GaN owning to lattice matching. On the other hand, the open gate geometry was found to affect the pH sensitivity obviously. Properly increasing the width and shortening the length of the open gate area could enhance the sensitivity. However, when the open gate width is too larger or too small, the pH sensitivity would be suppressed conversely. Designing an optimal ratio of the width to the length is important for achieving high sensitivity. This work suggests that the AlInN/GaN-based 2DEG carrier modulated devices would be good candidates for high-performance pH sensors and other related applications.
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Zhyrovetsky VM, Popovych DI, Savka SS, Serednytski AS. Nanopowder Metal Oxide for Photoluminescent Gas Sensing. NANOSCALE RESEARCH LETTERS 2017; 12:132. [PMID: 28235363 PMCID: PMC5318310 DOI: 10.1186/s11671-017-1891-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 01/17/2017] [Indexed: 06/06/2023]
Abstract
Gas sensing properties of metal oxide nanopowders (ZnO, TiO2, WO3, SnO2) with average diameters of 40-60 nm were analyzed by room-temperature photoluminescence spectroscopy. The influence of gas environment (O2, N2, H2, CO, CO2) on the emission intensity was investigated for metal oxide nanopowders with surface doped by impurities (Pt, Ag, Au, Sn, Ni or Cu). Established physicochemical regularities of modification of surface electronic states of initial and doped nanopowders during gas adsorption. The nature of metal oxide nanopowder gas-sensing properties (adsorption capacity, sensitivity, selectivity) has been established and the design and optimal materials for the construction of the multi-component sensing matrix have been selected.
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Affiliation(s)
- V M Zhyrovetsky
- Pidstryhach Institute for Applied Problems of Mechanics and Mathematics NASU, Naukova Str., 3b, Lviv, 79060, Ukraine
| | - D I Popovych
- Pidstryhach Institute for Applied Problems of Mechanics and Mathematics NASU, Naukova Str., 3b, Lviv, 79060, Ukraine.
- National University "Lvivska Polytechnika", Bandera Str., 12, Lviv, 79013, Ukraine.
| | - S S Savka
- Pidstryhach Institute for Applied Problems of Mechanics and Mathematics NASU, Naukova Str., 3b, Lviv, 79060, Ukraine
| | - A S Serednytski
- Pidstryhach Institute for Applied Problems of Mechanics and Mathematics NASU, Naukova Str., 3b, Lviv, 79060, Ukraine
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12
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Minh Triet N, Thai Duy L, Hwang BU, Hanif A, Siddiqui S, Park KH, Cho CY, Lee NE. High-Performance Schottky Diode Gas Sensor Based on the Heterojunction of Three-Dimensional Nanohybrids of Reduced Graphene Oxide-Vertical ZnO Nanorods on an AlGaN/GaN Layer. ACS APPLIED MATERIALS & INTERFACES 2017; 9:30722-30732. [PMID: 28825301 DOI: 10.1021/acsami.7b06461] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A Schottky diode based on a heterojunction of three-dimensional (3D) nanohybrid materials, formed by hybridizing reduced graphene oxide (RGO) with epitaxial vertical zinc oxide nanorods (ZnO NRs) and Al0.27GaN0.73(∼25 nm)/GaN is presented as a new class of high-performance chemical sensors. The RGO nanosheet layer coated on the ZnO NRs enables the formation of a direct Schottky contact with the AlGaN layer. The sensing results of the Schottky diode with respect to NO2, SO2, and HCHO gases exhibit high sensitivity (0.88-1.88 ppm-1), fast response (∼2 min), and good reproducibility down to 120 ppb concentration levels at room temperature. The sensing mechanism of the Schottky diode can be explained by the effective modulation of the reverse saturation current due to the change in thermionic emission carrier transport caused by ultrasensitive changes in the Schottky barrier of a van der Waals heterostructure between RGO and AlGaN layers upon interaction with gas molecules. Advances in the design of a Schottky diode gas sensor based on the heterojunction of high-mobility two-dimensional electron gas channel and highly responsive 3D-engineered sensing nanomaterials have potential not only for the enhancement of sensitivity and selectivity but also for improving operation capability at room temperature.
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Affiliation(s)
| | | | | | | | | | - Kyung-Ho Park
- Device Platform Laboratory, Korea Advanced Nano Fab Center , Suwon, Kyunggi-do 16229, Republic of Korea
| | - Chu-Young Cho
- Device Platform Laboratory, Korea Advanced Nano Fab Center , Suwon, Kyunggi-do 16229, Republic of Korea
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Abstract
Biosensing has found wide applications in biological and medical research, and in clinical diagnosis, environmental monitoring and other analytical tasks. Recognized as novel and outstanding transducing materials because of their superior and unique physical/chemical properties, group III nitride (III-nitride) nanomaterials have been introduced into biosensor development with remarkable advancements achieved in the past few decades. This paper presents the first comprehensive review on biosensor development with III-nitride nanomaterials. The review starts with the introduction of the material properties and biocompatibility of III-nitrides that are useful for biosensing. The focus is then placed on surface treatments of III-nitrides, which lay the foundation for biosensing, and on biosensing mechanisms where the exceptional properties of III-nitride nanomaterials lead to superior biosensing performance. From a practical point of view, techniques for biosensor fabrication are then summarized. Finally, existing biosensing applications and future directions are discussed.
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Affiliation(s)
- Xiao Li
- Department of Mechanical Engineering, McGill University, Montreal, Quebec H3A 0C3, Canada.
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14
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Electrodes for Semiconductor Gas Sensors. SENSORS 2017; 17:s17040683. [PMID: 28346349 PMCID: PMC5419796 DOI: 10.3390/s17040683] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 03/11/2017] [Accepted: 03/22/2017] [Indexed: 11/16/2022]
Abstract
The electrodes of semiconductor gas sensors are important in characterizing sensors based on their sensitivity, selectivity, reversibility, response time, and long-term stability. The types and materials of electrodes used for semiconductor gas sensors are analyzed. In addition, the effect of interfacial zones and surface states of electrode–semiconductor interfaces on their characteristics is studied. This study describes that the gas interaction mechanism of the electrode–semiconductor interfaces should take into account the interfacial zone, surface states, image force, and tunneling effect.
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15
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Abdulsattar MA. Chlorine gas reaction with ZnO wurtzoid nanocrystals as a function of temperature: a DFT study. J Mol Model 2017; 23:125. [PMID: 28316040 DOI: 10.1007/s00894-017-3309-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Accepted: 03/06/2017] [Indexed: 11/29/2022]
Abstract
In the present work, we applied density functional theory and temperature-dependent Gibbs free energy calculations to wurtzoid structures to explain the sensitivity of ZnO nanocrystals towards chlorine molecules. In agreement with experimental findings, our results revealed that chlorine sensing under ambient conditions is feasible. Higher temperatures increased the sensitivity of ZnO nanocrystals towards chlorine gas molecules. Peak calculated sensitivities were in the temperature ranges (167-220 °C), (447-578 °C) and (952-1159 °C), which is in good agreement with experimentally determined temperatures. According to the calculated Gibbs free energy, these three ranges correspond to the van der Waals attachment of Cl2 molecules on Zn-polar sites, van der Waals attachment of Cl2 molecules on O sites, and dissociation of Cl2 molecules on ZnO nanocrystal surfaces, respectively. The removal of chlorine atoms from the surface of ZnO nanocrystals is difficult at low temperatures because of the high electron affinity of chlorine gas atoms, which results in a long recovery time and accumulation of chlorine atoms and molecules on the ZnO surface. Atomic charges and charge transfer are depicted using natural bond orbital analysis to explain the present mechanisms.
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16
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Ranwa S, Barala SS, Fanetti M, Kumar M. Effect of gamma irradiation on Schottky-contacted vertically aligned ZnO nanorod-based hydrogen sensor. NANOTECHNOLOGY 2016; 27:345502. [PMID: 27418478 DOI: 10.1088/0957-4484/27/34/345502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We report the impact of gamma irradiation on the performance of a gold Schottky-contacted ZnO nanorod-based hydrogen sensor. RF-sputtered vertically aligned highly c-axis-oriented ZnO NRs were grown on Si(100) substrate. X-ray diffraction shows no significant change in crystal structure at low gamma doses from 1 to 5 kGy. As gamma irradiation doses increase to 10 kGy, the single crystalline ZnO structure converts to polycrystalline. The photoluminescence spectra also shows suppression of the near-band emission peak and the huge wide-band spectrum indicates the generation of structural defects at high gamma doses. At 1 kGy, the hydrogen sensor response was enhanced from 67% to 77% for 1% hydrogen in pure argon at a 150 °C operating temperature. However, at 10 kGy, the relative response decreases to 33.5%. High gamma irradiation causes displacement damage and defects in ZnO NRs, and as a result, degrades the sensor's performance as a result. Low gamma irradiation doses activate the ZnO NR surface through ionization, which enhances the sensor performance. The relative response of the hydrogen sensor was enhanced by ∼14.9% with respect to pristine ZnO using 1 kGy gamma ray treatment.
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Affiliation(s)
- Sapana Ranwa
- Department of Electrical Engineering, Indian Institute of Technology Jodhpur, Jodhpur-342011, India
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17
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Solid-State Gas Sensors: Sensor System Challenges in the Civil Security Domain. MATERIALS 2016; 9:ma9010065. [PMID: 28787865 PMCID: PMC5456536 DOI: 10.3390/ma9010065] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 01/11/2016] [Accepted: 01/12/2016] [Indexed: 11/30/2022]
Abstract
The detection of military high explosives and illicit drugs presents problems of paramount importance in the fields of counter terrorism and criminal investigation. Effectively dealing with such threats requires hand-portable, mobile and affordable instruments. The paper shows that solid-state gas sensors can contribute to the development of such instruments provided the sensors are incorporated into integrated sensor systems, which acquire the target substances in the form of particle residue from suspect objects and which process the collected residue through a sequence of particle sampling, solid-vapor conversion, vapor detection and signal treatment steps. Considering sensor systems with metal oxide gas sensors at the backend, it is demonstrated that significant gains in sensitivity, selectivity and speed of response can be attained when the threat substances are sampled in particle as opposed to vapor form.
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18
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Liu X, Cheng S, Liu H, Hu S, Zhang D, Ning H. A survey on gas sensing technology. SENSORS 2012; 12:9635-65. [PMID: 23012563 PMCID: PMC3444121 DOI: 10.3390/s120709635] [Citation(s) in RCA: 350] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 06/18/2012] [Accepted: 07/13/2012] [Indexed: 11/25/2022]
Abstract
Sensing technology has been widely investigated and utilized for gas detection. Due to the different applicability and inherent limitations of different gas sensing technologies, researchers have been working on different scenarios with enhanced gas sensor calibration. This paper reviews the descriptions, evaluation, comparison and recent developments in existing gas sensing technologies. A classification of sensing technologies is given, based on the variation of electrical and other properties. Detailed introduction to sensing methods based on electrical variation is discussed through further classification according to sensing materials, including metal oxide semiconductors, polymers, carbon nanotubes, and moisture absorbing materials. Methods based on other kinds of variations such as optical, calorimetric, acoustic and gas-chromatographic, are presented in a general way. Several suggestions related to future development are also discussed. Furthermore, this paper focuses on sensitivity and selectivity for performance indicators to compare different sensing technologies, analyzes the factors that influence these two indicators, and lists several corresponding improved approaches.
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Affiliation(s)
- Xiao Liu
- School of Electronic and Information Engineering, Beihang University, Beijing 100191, China; E-Mails: (X.L.); (S.C.); (H.L.); (S.H.)
| | - Sitian Cheng
- School of Electronic and Information Engineering, Beihang University, Beijing 100191, China; E-Mails: (X.L.); (S.C.); (H.L.); (S.H.)
| | - Hong Liu
- School of Electronic and Information Engineering, Beihang University, Beijing 100191, China; E-Mails: (X.L.); (S.C.); (H.L.); (S.H.)
| | - Sha Hu
- School of Electronic and Information Engineering, Beihang University, Beijing 100191, China; E-Mails: (X.L.); (S.C.); (H.L.); (S.H.)
| | - Daqiang Zhang
- School of Computer Science, Nanjing Normal University, Nanjing 210097, China; E-Mail:
| | - Huansheng Ning
- School of Electronic and Information Engineering, Beihang University, Beijing 100191, China; E-Mails: (X.L.); (S.C.); (H.L.); (S.H.)
- Author to whom correspondence should be addressed; E-Mail:
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19
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Gu H, Wang Z, Hu Y. Hydrogen gas sensors based on semiconductor oxide nanostructures. SENSORS 2012; 12:5517-50. [PMID: 22778599 PMCID: PMC3386698 DOI: 10.3390/s120505517] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Revised: 04/01/2012] [Accepted: 04/25/2012] [Indexed: 11/16/2022]
Abstract
Recently, the hydrogen gas sensing properties of semiconductor oxide (SMO) nanostructures have been widely investigated. In this article, we provide a comprehensive review of the research progress in the last five years concerning hydrogen gas sensors based on SMO thin film and one-dimensional (1D) nanostructures. The hydrogen sensing mechanism of SMO nanostructures and some critical issues are discussed. Doping, noble metal-decoration, heterojunctions and size reduction have been investigated and proved to be effective methods for improving the sensing performance of SMO thin films and 1D nanostructures. The effect on the hydrogen response of SMO thin films and 1D nanostructures of grain boundary and crystal orientation, as well as the sensor architecture, including electrode size and nanojunctions have also been studied. Finally, we also discuss some challenges for the future applications of SMO nanostructured hydrogen sensors.
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Affiliation(s)
- Haoshuang Gu
- Faculty of Physics and Electronic Technology, Hubei University, Wuhan 430062, China.
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Field CR, In HJ, Begue NJ, Pehrsson PE. Vapor Detection Performance of Vertically Aligned, Ordered Arrays of Silicon Nanowires with a Porous Electrode. Anal Chem 2011; 83:4724-8. [DOI: 10.1021/ac200779d] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Christopher R. Field
- Chemistry Division, U.S. Naval Research Laboratory, Washington, DC 20375, United States
| | - Hyun Jin In
- Post-Doctoral Research Associateship, National Research Council, Washington, DC 20001, United States
| | - Nathan J. Begue
- Post-Doctoral Research Associateship, National Research Council, Washington, DC 20001, United States
| | - Pehr E. Pehrsson
- Chemistry Division, U.S. Naval Research Laboratory, Washington, DC 20375, United States
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Noh JS, Lee JM, Lee W. Low-dimensional palladium nanostructures for fast and reliable hydrogen gas detection. SENSORS 2011; 11:825-51. [PMID: 22346605 PMCID: PMC3274109 DOI: 10.3390/s110100825] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Revised: 12/22/2010] [Accepted: 01/10/2011] [Indexed: 11/16/2022]
Abstract
Palladium (Pd) has received attention as an ideal hydrogen sensor material due to its properties such as high sensitivity and selectivity to hydrogen gas, fast response, and operability at room temperature. Interestingly, various Pd nanostructures that have been realized by recent developments in nanotechnologies are known to show better performance than bulk Pd. This review highlights the characteristic properties, issues, and their possible solutions of hydrogen sensors based on the low-dimensional Pd nanostructures with more emphasis on Pd thin films and Pd nanowires. The finite size effects, relative strengths and weaknesses of the respective Pd nanostructures are discussed in terms of performance, manufacturability, and practical applicability.
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Affiliation(s)
- Jin-Seo Noh
- Department of Materials Science and Engineering, Yonsei University, Seoul 120-749, Korea.
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Effect of Coated Platinum Thickness on Hydrogen Detection Sensitivity of Graphene-Based Sensors. ACTA ACUST UNITED AC 2011. [DOI: 10.1149/1.3589250] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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