Impedance Spectroscopic Inspection Toward Sensitivity Enhancement of Ag-Doped WO3 Nanofiber-Based Carbon Monoxide Gas Sensor

This work reports the impedance analysis and carbon monoxide gas sensing response of tungsten oxide (WO3) nanofibers with silver (Ag) nanoparticle doping. The Ag-doped WO3 nanofibers were prepared by an electrospinning technique. The impedance spectroscopic measurements of undoped and Ag-doped WO3 nanofibers were performed to study the contribution of electrical parameters involved in the electron transport. The impedance modeling obtained from the fitted Nyquist plot shows that the RC components attributed to Ag-WO3 interface are introduced to the system upon Ag addition. Carbon monoxide (CO) gas detection was carried out by resistance measurement using a DC method. The sensitivity of Ag-doped WO3 nanofibers is found to be greater than that of the undoped sample. The improved sensitivity is derived from the high interface resistance between Ag and WO3 grains. The contribution of Ag dopants is conceived to induce electronic structure alteration of the sensor material.

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Selective gas detection using Mn3O4/WO3 composites as a sensing layer

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.10.140 ◽

2019 ◽

Vol 10 ◽

pp. 1423-1433 ◽

Cited By ~ 2

Author(s):

Yongjiao Sun ◽

Zhichao Yu ◽

Wenda Wang ◽

Pengwei Li ◽

Gang Li ◽

...

Keyword(s):

Carbon Monoxide ◽

Hydrogen Sulfide ◽

Gas Sensing ◽

Gas Detection ◽

Facile Hydrothermal Method ◽

Potential Applications ◽

Different Temperatures ◽

Different Gases ◽

Sensing Performance ◽

Mn Concentrations

Pure WO3 sensors and Mn3O4/WO3 composite sensors with different Mn concentrations (1 atom %, 3 atom % and 5 atom %) were successfully prepared through a facile hydrothermal method. As gas sensing materials, their sensing performance at different temperatures was systematically investigated for gas detection. The devices displayed different sensing responses toward different gases at specific temperatures. The gas sensing performance of Mn3O4/WO3 composites (especially at 3 atom % Mn) were far improved compared to sensors based on pure WO3, where the improvement is related to the heterojunction formed between the two metal oxides. The sensor based on the Mn3O4/WO3 composite with 3 atom % Mn showed a high selective response to hydrogen sulfide (H2S), ammonia (NH3) and carbon monoxide (CO) at working temperatures of 90 °C, 150 °C and 210 °C, respectively. The demonstrated superior selectivity opens the door for potential applications in gas recognition and detection.

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Recent Advances in Spectroscopic Gas Sensing With Micro/Nano-Structured Optical Fibers

Photonic Sensors ◽

10.1007/s13320-021-0627-4 ◽

2021 ◽

Vol 11 (2) ◽

pp. 141-157

Author(s):

Wei Jin ◽

Haihong Bao ◽

Pengcheng Zhao ◽

Yan Zhao ◽

Yun Qi ◽

...

Keyword(s):

Carbon Monoxide ◽

Optical Fiber ◽

Optical Fibers ◽

Gas Sensing ◽

Gas Detection ◽

Direct Absorption ◽

Detection Systems ◽

Recent Advances ◽

Stimulated Raman

AbstractWith micro- and nano-structured optical fibers, parts-per-million to parts-per-trillion level gas detection has been demonstrated for a range of gases such as methane, acetylene, ethane, carbon monoxide, hydrogen, and oxygen. We review the recent development in optical fiber gas cells and gas detection systems based on direct absorption, photothermal, photoacoustic, and stimulated Raman spectroscopies.

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Synthesis of graphitic carbon nitride nanosheets decorated spherical‐like nickel oxide composites for carbon monoxide gas‐sensing application

Micro & Nano Letters ◽

10.1049/mnl.2019.0436 ◽

2019 ◽

Vol 14 (14) ◽

pp. 1410-1413

Author(s):

Xiaoze Li ◽

Wendi Tian ◽

Jianbo Jia ◽

Jianliang Cao ◽

Zhanying Zhang ◽

...

Keyword(s):

Carbon Monoxide ◽

Nickel Oxide ◽

Carbon Nitride ◽

Gas Sensing ◽

Graphitic Carbon ◽

Graphitic Carbon Nitride ◽

Sensing Application ◽

Carbon Nitride Nanosheets ◽

Oxide Composites

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Influence of the aluminium doping on the physical and gas sensing properties of SnO2 for H2 gas detection

Sensors and Actuators B Chemical ◽

10.1016/j.snb.2021.129633 ◽

2021 ◽

Vol 340 ◽

pp. 129633 ◽

Cited By ~ 1

Author(s):

Ausama I. Khudiar ◽

Attarid M. Oufi

Keyword(s):

Gas Sensing ◽

Gas Detection ◽

Sensing Properties ◽

Gas Sensing Properties ◽

Aluminium Doping

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Recent Advances in ZnO-Based Carbon Monoxide Sensors: Role of Doping

Sensors ◽

10.3390/s21134425 ◽

2021 ◽

Vol 21 (13) ◽

pp. 4425

Author(s):

Ana María Pineda-Reyes ◽

María R. Herrera-Rivera ◽

Hugo Rojas-Chávez ◽

Heriberto Cruz-Martínez ◽

Dora I. Medina

Keyword(s):

Carbon Monoxide ◽

High Performance ◽

Gas Sensing ◽

Experimental Studies ◽

Electrical Performance ◽

Long Term Stability ◽

Sensing Applications ◽

Recent Advances ◽

Sensitivity And Selectivity ◽

Doped Zno

Monitoring and detecting carbon monoxide (CO) are critical because this gas is toxic and harmful to the ecosystem. In this respect, designing high-performance gas sensors for CO detection is necessary. Zinc oxide-based materials are promising for use as CO sensors, owing to their good sensing response, electrical performance, cost-effectiveness, long-term stability, low power consumption, ease of manufacturing, chemical stability, and non-toxicity. Nevertheless, further progress in gas sensing requires improving the selectivity and sensitivity, and lowering the operating temperature. Recently, different strategies have been implemented to improve the sensitivity and selectivity of ZnO to CO, highlighting the doping of ZnO. Many studies concluded that doped ZnO demonstrates better sensing properties than those of undoped ZnO in detecting CO. Therefore, in this review, we analyze and discuss, in detail, the recent advances in doped ZnO for CO sensing applications. First, experimental studies on ZnO doped with transition metals, boron group elements, and alkaline earth metals as CO sensors are comprehensively reviewed. We then focused on analyzing theoretical and combined experimental–theoretical studies. Finally, we present the conclusions and some perspectives for future investigations in the context of advancements in CO sensing using doped ZnO, which include room-temperature gas sensing.

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Carbon monoxide gas sensing features of zinc oxide nanoneedles: practical selectivity and long-term stability

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-019-01111-8 ◽

2019 ◽

Vol 30 (11) ◽

pp. 10073-10081 ◽

Cited By ~ 4

Author(s):

Ali Jamshidi Bandari ◽

Shahruz Nasirian

Keyword(s):

Carbon Monoxide ◽

Zinc Oxide ◽

Gas Sensing ◽

Term Stability ◽

Long Term Stability

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High-Sensitive Numerical Gas Detection Using LSPR Effect and Fano Resonance in a Slotted MDM Structure

Photonic Sensors ◽

10.1007/s13320-021-0634-5 ◽

2021 ◽

Author(s):

Hai Liu ◽

Benlei Zhao ◽

Xu Zhang ◽

Hancheng Zhang ◽

Bo Wu ◽

...

Keyword(s):

Fano Resonance ◽

Gas Sensing ◽

Field Enhancement ◽

Fast Response ◽

Gas Detection ◽

Localized Surface Plasmon ◽

Gas Sensitivity ◽

Combined Use ◽

Coherent Coupling ◽

Lspr Effect

AbstractA high-sensitive numerical measurement of methane based on the combined use of the localized surface plasmon resonance (LSPR) and Fano resonance in a slotted metal-dielectric-metal (MDM) periodic structure is numerically investigated. A groove is etched in an original MDM structure to excite the diploe mode at both sides of the groove, and the coherent coupling of two dipole modes is enhanced to realize a fast response, which is beneficial to gas-sensing. The influence of geometric parameters on the reflection spectra and methane sensitivity are analyzed to obtain optimal geometry. Moreover, an etching ring is introduced on the top metal to further raise the coupling area and coupling strength. The Fano resonance is subtly integrated into the optimized structure with asymmetry to achieve greater gas sensitivity. After the introduction of the Fano resonance, the field enhancement caused by the LSPR effect becomes greater and the methane sensitivity can reach up to 8.421 nm/% in numerical calculations, which increases 56.8% more than that of the original one. The combined use of the LSPR and Fano resonance in an optimized MDM structure provides an effective method for high-sensitive gas detection.

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Analysis and Mitigation of Sub-Synchronous Resonance for Doubly Fed Induction Generator under VSG Control

Energies ◽

10.3390/en13071582 ◽

2020 ◽

Vol 13 (7) ◽

pp. 1582

Author(s):

Yingzong Jiao ◽

Feng Li ◽

Hui Dai ◽

Heng Nian

Keyword(s):

Reactive Power ◽

Synchronous Generator ◽

Impedance Analysis ◽

Damping Factor ◽

Renewable Power ◽

Induction Generators ◽

Parameter Configuration ◽

Impedance Modeling ◽

Doubly Fed ◽

Series Capacitor Compensation

This paper presents the analysis and mitigation of sub-synchronous resonance (SSR) for doubly fed induction generators (DFIG) under virtual synchronous generator (VSG) control, based on impedance methods. VSGs are considered to have grid-supporting ability and good stability in inductance-based weak grids, and are implemented in renewable power generations, including DFIG systems. However, stability analyses of VSGs for DFIG connecting with series capacitor compensation are absent. Therefore, this paper focuses on the analysis and mitigation of SSR for DFIG under VSG control. Impedance modeling of DFIG systems is used to analyze SSR stability. Based on impedance analysis, the influence of VSG control parameters and the configuration of damping factor of reactive power are discussed. Next, a parameter configuration method to mitigate SSR is proposed. Finally, time-domain simulation and fast fourier transform (FFT) results are given to validate the correctness and effectiveness of the impedance model and parameter configuration methods.

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