Utilization of Mass and Elastic Loading in Oxide Materials Based SAW Devices for the Detection of Mustard Gas Simulant

2012 ◽  
Vol 488-489 ◽  
pp. 1558-1562 ◽  
Author(s):  
V Bhasker Raj ◽  
Harpreet Singh ◽  
A. Theodore Nimal ◽  
M.U. Sharma ◽  
Monika Tomar ◽  
...  
Keyword(s):  
Thin Film ◽  
Visible Region ◽  
Mustard Gas ◽  
Oxide Materials ◽  
Mass Loading ◽  
Oxide Coatings ◽  
Saw Sensor ◽  
Saw Devices ◽  
Sensitivity And Selectivity ◽  
Elastic Loading

The properties (mass loading and elastic changes) of different oxide materials (ZnO, TeO2, SnO2, TiO2) in thin film form has been explored for the enhanced detection of DBS (di butyl sulphide), a simulant of sulphur mustard gas. All the four oxide materials are deposited on to the surface of SAW (Surface Acoustic Wave) devices to impart sensitivity and selectivity. ZnO and SnO2 films are crystalline whereas TiO2 and TeO2 films are amorphous in nature. All the films are transparent with transparency greater than 75 % in the visible region. The SAW devices coated with different oxide materials were placed in the feedback loop of colpitt oscillator. With the exposure of DBS vapors, differential frequency increases for TiO2 thin films whereas for other oxide coatings (ZnO, TeO2 and SnO2) it decreases. ZnO coated SAW sensor is found to be maximum sensitive to DBS vapors. Investigation of sensing mechanism revealed that mass loading effect is pronounced in TiO2 thin film whereas for other films change in elasticity is dominant. The oxide coatings are very less sensitive to the other interferants.

scholarly journals Plasmon-Enhanced Sunlight Harvesting in Thin-Film Solar Cell by Randomly Distributed Nanoparticle Array

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1380
Author(s):  
Marwa M. Tharwat ◽  
Ashwag Almalki ◽  
Amr M. Mahros
Keyword(s):  
Thin Film ◽  
Solar Cells ◽  
Solar Cell ◽  
Near Infrared ◽  
Structural Parameters ◽  
Visible Region ◽  
Nanoparticle Array ◽  
Solar Energy Harvesting ◽  
Infra Red ◽  
Crucial Parameter

In this paper, a randomly distributed plasmonic aluminum nanoparticle array is introduced on the top surface of conventional GaAs thin-film solar cells to improve sunlight harvesting. The performance of such photovoltaic structures is determined through monitoring the modification of its absorbance due to changing its structural parameters. A single Al nanoparticle array is integrated over the antireflective layer to boost the absorption spectra in both visible and near-infra-red regimes. Furthermore, the planar density of the plasmonic layer is presented as a crucial parameter in studying and investigating the performance of the solar cells. Then, we have introduced a double Al nanoparticle array as an imperfection from the regular uniform single array as it has different size particles and various spatial distributions. The comparison of performances was established using the enhancement percentage in the absorption. The findings illustrate that the structural parameters of the reported solar cell, especially the planar density of the plasmonic layer, have significant impacts on tuning solar energy harvesting. Additionally, increasing the plasmonic planar density enhances the absorption in the visible region. On the other hand, the absorption in the near-infrared regime becomes worse, and vice versa.

scholarly journals Synthesis, Crystallography, Microstructure, Crystal Defects, Optical and Optoelectronic Properties of ZnO:CeO2 Mixed Oxide Thin Films

Photonics ◽  
2020 ◽  
Vol 7 (4) ◽  
pp. 112
Author(s):  
Qais M. Al-Bataineh ◽  
Mahmoud Telfah ◽  
Ahmad A. Ahmad ◽  
Ahmad M. Alsaad ◽  
Issam A. Qattan ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Refractive Index ◽  
Mixed Oxide ◽  
Visible Region ◽  
Functional Materials ◽  
Crystal Defects ◽  
Optoelectronic Properties ◽  
Oxide Thin Films ◽  
Pure Ceo2

We report the synthesis and characterization of pure ZnO, pure CeO2, and ZnO:CeO2 mixed oxide thin films dip-coated on glass substrates using a sol-gel technique. The structural properties of as-prepared thin film are investigated using the XRD technique. In particular, pure ZnO thin film is found to exhibit a hexagonal structure, while pure CeO2 thin film is found to exhibit a fluorite cubic structure. The diffraction patterns also show the formation of mixed oxide materials containing well-dispersed phases of semi-crystalline nature from both constituent oxides. Furthermore, optical properties of thin films are investigated by performing UV–Vis spectrophotometer measurements. In the visible region, transmittance of all investigated thin films attains values as high as 85%. Moreover, refractive index of pure ZnO film was found to exhibit values ranging between 1.57 and 1.85 while for CeO2 thin film, it exhibits values ranging between 1.73 and 2.25 as the wavelength of incident light decreases from 700 nm to 400 nm. Remarkably, refractive index of ZnO:CeO2 mixed oxide-thin films are tuned by controlling the concentration of CeO2 properly. Mixed oxide-thin films of controllable refractive indices constitute an important class of smart functional materials. We have also investigated the optoelectronic and dispersion properties of ZnO:CeO2 mixed oxide-thin films by employing well-established classical models. The melodramatic boost of optical and optoelectronic properties of ZnO:CeO2 mixed oxide thin films establish a strong ground to modify these properties in a skillful manner enabling their use as key potential candidates for the fabrication of scaled optoelectronic devices and thin film transistors.

scholarly journals Nanostructure-Enhanced Surface Acoustic Waves Biosensor and Its Computational Modeling

2009 ◽  
Vol 2009 ◽  
pp. 1-11 ◽  
Author(s):  
Guigen Zhang
Keyword(s):  
Acoustic Waves ◽  
High Performance ◽  
Surface Acoustic Waves ◽  
Active Surface ◽  
Underlying Mechanism ◽  
Saw Sensor ◽  
Saw Devices ◽  
Operational Capabilities ◽  
Sensing Platform ◽  
Enhanced Surface

Surface acoustic wave (SAW) devices are considered to be very promising in providing a high-performance sensing platform with wireless and remote operational capabilities. In this review, the basic principles of SAW devices and Love-mode SAW-based biosensors are discussed first to illustrate the need for surface enhancement for the active area of a SAW sensor. Then some of the recent efforts made to incorporate nanostructures into SAW sensors are summarized. After that, a computational approach to elucidate the underlying mechanism for the operations of a Love-mode SAW biosensor with nanostructured active surface is discussed. Finally, a modeling example for a Love-mode SAW sensor with skyscraper nanopillars added to in its active surface along with some selected results is presented.

Characteristics and Potential Application of Thermally Sprayed Thin Film Coatings

2000 ◽  
Author(s):  
M. Loch ◽  
G. Barbezat
Keyword(s):  
Thin Film ◽  
New Technology ◽  
Functional Coatings ◽  
Oxide Coatings ◽  
Film Coatings ◽  
Thin Film Coatings ◽  
Thermally Sprayed Coatings ◽  
Short Time ◽  
Thermally Sprayed ◽  
Sprayed Coatings

Abstract LPPS Thin Film is a new technology for the production of thin functional coatings. The coatings produced can fill the well known gap of coating thickness between conventional thin films (PVD, CVD and others) and conventional thermally sprayed coatings (Plasma, HVOF and others). The application is successful, if the advantages of the new technology (large areas can be dense coated within a very short time) are combined with the specific properties of thermally sprayed coatings to the benefit of the intended application. Beside the technology of LPPS Thin Film and it's characteristics the paper will summarise important properties of Alumina described in the literature and present some corresponding properties of Aluminium oxide coatings produced by LPPS Thin Film.

scholarly journals Donor Acceptor Copolymers from Cyclopentannulation Polymerizations with Dicyclopenta[cd,jk]pyrene and Dicyclopenta[cd,lm]perylene Acceptors

2020 ◽  
Author(s):  
Ain Uddin ◽  
Kyle Plunkett
Keyword(s):  
Thin Film ◽  
Cyclic Voltammetry ◽  
Light Absorption ◽  
Visible Region ◽  
Optoelectronic Properties ◽  
Band Gaps ◽  
Molecular Weights ◽  
Palladium Catalyzed ◽  
Donor Acceptor ◽  
Film Absorption

A series of donor-acceptor copolymers with dicyclopenta[cd,jk]pyrene and dicyclopenta[cd,lm]perylene acceptor units was prepared via palladium catalyzed cyclopenta-annulation reactions. The acceptor units were paired with diethynyl containing donor groups based on benzo[1,2-b:4,5-b']dithiophene, thieno[3,2-b]thiophene, and 4-octyl-4H-dithieno[3,2-b:2',3'-d]pyrrole to create six polymer variants. The cyclopentannulation polymerization resulted in copolymers with molecular weights (Mn) of 6-14 kDa and broad light absorption in the visible region with band gaps of 1.38-1.85 eV. The synthetic methodology, as well as optoelectronic properties, including thin-film absorption and cyclic voltammetry, of the donor-acceptor copolymers are presented.<br> <br><br>

scholarly journals In-Situ Process and Simulation of High-Performance Piezoelectric-on-Silicon Substrate for SAW Sensor

2021 ◽  
Vol 8 ◽  
Author(s):  
Rui Ma ◽  
Weiguo Liu ◽  
Xueping Sun ◽  
Shun Zhou
Keyword(s):  
Thin Film ◽  
Lithium Niobate ◽  
High Performance ◽  
Electromechanical Coupling ◽  
Substrate Material ◽  
Electromechanical Coupling Coefficient ◽  
Bonding Layer ◽  
Saw Sensor ◽  
Rayleigh Mode

This paper studied the manufacturing process of Piezoelectric-on-Silicon (POS) substrate which integrates 128° Y–X Lithium niobate thin film and silicon wafer using Smart-Cut technology. The blistering and exfoliation processes of the He as-implanted LN crystal under different annealing temperatures are observed by the in-situ method. Unlike the conventional polishing process, the stripping mechanism of the Lithium niobate thin film is changed by controlling annealing temperature, which can improve the surface morphology of the peeling lithium niobate thin film. We prepared the 128° Y–X POS substrate with high single-crystal Lithium niobate thin film and surface roughness of 3.91 nm through Benzocyclobutene bonding. After simulating the surface acoustic wave (SAW) characteristics of the POS substrate, the results demonstrate that the Benzocyclobutene layer not only performs as a bonding layer but also can couple more vibrations into the LN thin film. The electromechanical coupling coefficient of the POS substrate is up to 7.59% in the Rayleigh mode when hLN/λ is 0.3 and hBCB/λ is 0.1. Therefore, as a high-performance substrate material, the POS substrate has proved to be an efficient method to miniaturize and integrate the SAW sensor.

High Haze and Low Resistive MgO/AZO Bi-layer Transparent Conducting Oxide for Thin Film Solar Cells

2011 ◽  
Vol 1327 ◽  
Author(s):  
Dong Won Kang ◽  
Jong Seok Woo ◽  
Sung Hwan Choi ◽  
Seung Yoon Lee ◽  
Heon Min. Lee ◽  
...  
Keyword(s):  
Thin Film ◽  
Solar Cells ◽  
Solar Cell ◽  
Silicon Solar Cell ◽  
Transparent Conducting Oxide ◽  
Visible Region ◽  
Xrd Analysis ◽  
Thin Film Solar Cells ◽  
Microcrystalline Silicon ◽  
Transparent Conducting

ABSTRACTWe have propsed MgO/AZO bi-layer transparent conducting oxide (TCO) for thin film solar cells. From XRD analysis, it was observed that the full width at half maximum of AZO decreased when it was grown on MgO precursor. The Hall mobility of MgO/AZO bi-layer was 17.5cm2/Vs, whereas that of AZO was 20.8cm2/Vs. These indicated that the crystallinity of AZO decreased by employing MgO precursor. However, the haze (=total diffusive transmittance/total transmittance) characteristics of highly crystalline AZO was significantly improved by MgO precursor. The average haze in the visible region increased from 14.3 to 48.2%, and that in the NIR region increased from 6.3 to 18.9%. The reflectance of microcrystalline silicon solar cell was decreased and external quantum efficiency was significantly improved by applying MgO/AZO bi-layer TCO. The efficiency of microcrystalline silicon solar cell with MgO/AZO bi-layer front TCO was 6.66%, whereas the efficiency of one with AZO single TCO was 5.19%.

scholarly journals Fabrication and Characterisation of ZnO Thin Film by Sol–Gel Technique

2019 ◽  
Vol 61 (1) ◽  
pp. 64-70
Author(s):  
Said Benramache
Keyword(s):  
Thin Film ◽  
Sol Gel ◽  
Visible Region ◽  
Average Crystallite Size ◽  
Hexagonal Wurtzite Structure ◽  
Optical Transmittance ◽  
Band Gap Energy ◽  
Zno Thin Film ◽  
Optimal Value ◽  
Type Semiconductor

AbstractWe investigated the structural and optical properties of zinc oxide (ZnO) thin film as the n-type semiconductor. In this work, the sol–gel method used to fabricate ZnO thin film on glass substrate with 0.5 mol/l of zinc acetate dehydrates. The crystals quality of the thin film analyzed by X-ray diffraction and the optical transmittance was carried out by an ultraviolet-visible spectrophotometer. The DRX analyses indicated that ZnO film have polycrystalline nature and hexagonal wurtzite structure with (002) preferential orientation and the measured average crystallite size of ZnO of 207.9 nm. The thin film exhibit average optical transparency about 90 %, in the visible region, found that optical band gap energy was 3.282 eV, the Urbach energy also was calculated from optical transmittance to optimal value is 196.7 meV.

Sign in / Sign up

Export Citation Format

Share Document