Conductometric assisted ZnO and polypyrole composite based NH3 gas sensor

Abstract Metal oxides are excellent choices as base materials in emerging technologies in the field of Gas Sensors. In this work, an effort is made to prepare the ZnO and polypyrrole composite thin film using sol-gel technique. Nanocomposite thins film was prepared using spin coating on glass substrates for ammonia gas sensing. ZnO and polypyrrole sols were prepared using sol-gel technique and thin films were prepared by using spin coater. The nanocomposite thin films were prepared by varying the percentage composition of ZnO and Polypyrrole. Structural, optical and morphological properties of the prepared films were done using XRD, UV-Visible and SEM studies. The films were separately prepared on Inter-Digital Transducers for gas sensing applications. Gas sensing response characteristics of the prepared sensor were performed using laboratory. The sensing response of the prepared films is observed and found to be maximum (~33) for the 70%PPy+30%ZnO film at a relatively low operating temperature of about 150°C.

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Formation of Vanadium Oxide Thin Films Prepared from Aqueous Sol-Gel System

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.605.79 ◽

2014 ◽

Vol 605 ◽

pp. 79-82 ◽

Cited By ~ 1

Author(s):

Olivier Monfort ◽

Tomas Roch ◽

Maros Gregor ◽

Leonid Satrapinskyy ◽

Tomas Plecenik ◽

...

Keyword(s):

Thin Films ◽

Vanadium Oxide ◽

Spin Coating ◽

Gas Sensing ◽

Sol Gel ◽

Oxide Thin Films ◽

Glass Substrates ◽

Sensing Applications ◽

Vanadium Oxide Thin Films ◽

Deposited Films

Vanadium oxide thin films are promising materials for various applications. Much attention has been devoted to thermotropic VO2(M/R) films which exhibit semiconductor-conductor phase transition at 67 °C making them excellent materials for switching applications. Non-thermotropic VO2(B) films are semiconducting and have layered structure which makes them interesting for gas sensing applications. Vanadium pentoxide films are also of great interest for photocatalytic production of H2by H2O decomposition as well as for gas sensing. In this paper the preparation of vanadium oxide thin films by using the spin coating of V2O5·nH2O aqueous gel on Si/SiO2and lime-glass substrates is reported. The as-deposited films were annealed in either air or H2/Ar atmosphere at normal or low pressure in order to prepare V2O5and VO2thin films. The obtained samples were characterized by XRD and SEM.

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Preparation and characterization of V2O5 doped SiO2-TiO2 thin films

Open Engineering ◽

10.2478/s13531-011-0041-6 ◽

2012 ◽

Vol 2 (1) ◽

Author(s):

Marek Nocuń ◽

Sławomir Kwaśny

Keyword(s):

Thin Films ◽

Band Gap ◽

Photoelectron Spectroscopy ◽

Sol Gel ◽

Dip Coating ◽

Band Gap Energy ◽

Tio2 Thin Films ◽

Glass Substrates ◽

Gel Technique

AbstractIn our investigation, V doped SiO2/TiO2 thin films were prepared on glass substrates by dip coating sol-gel technique. Chemical composition of the samples was studied by X-ray photoelectron spectroscopy (XPS). Transmittance of the samples was characterized using UV-VIS spectrophotometry. Subsequently band-gap energy (Eg) was estimated for these films. Powders obtained from sols were characterized by FTIR spectroscopy. It was found that vanadium decreases optical band gap of SSiO2/TiO2 films.

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Sol–gel cobalt oxide–silica nanocomposite thin films for gas sensing applications

Thin Solid Films ◽

10.1016/j.tsf.2007.07.197 ◽

2008 ◽

Vol 516 (7) ◽

pp. 1499-1502 ◽

Cited By ~ 16

Author(s):

V. Musat ◽

E. Fortunato ◽

A.M. Botelho do Rego ◽

R. Monteiro

Keyword(s):

Thin Films ◽

Cobalt Oxide ◽

Gas Sensing ◽

Sol Gel ◽

Sensing Applications ◽

Nanocomposite Thin Films ◽

Silica Nanocomposite

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TiO2 Nanopowders for Sensing Applications; A Comparison between Traditional and Hydrothermal Synthesis Way

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.45.205 ◽

2006 ◽

Vol 45 ◽

pp. 205-208 ◽

Cited By ~ 3

Author(s):

Marco Nagliati ◽

M.C. Carotta ◽

S. Gherardi ◽

Isidoro Giorgio Lesci ◽

G. Martinelli

Keyword(s):

Gas Sensing ◽

Sol Gel ◽

Spherical Shape ◽

Morphological Properties ◽

Fundamental Parameter ◽

Fixed Temperature ◽

Sensing Applications ◽

Organometallic Precursor ◽

Sem Analyses

Aim of the work is to compare the morphological properties of TiO2 powders obtained by different methods. The microstructure of powders is a fundamental parameter to judge if the material is suitable for gas sensing. Materials for chemical sensors have to be composed by nanometric and spherical shaped grains sintered in controlled conditions aimed to obtain Schottky barriers. We investigated a traditional sol-gel (SG) and an hydrothermal (HY) approach to obtain titanium dioxide powders. The same starting materials were chosen for both SG and HY method, a Ti-organometallic precursor and, as solvent, an hydroalcoholic solution. The work is focused on the different methodology and on the outcome related to the two methods (we describe step by step both of them). HY TiO2 powder shows smaller grains than SG TiO2 maintaining spherical shape. A comparison among different handled HY powders shows the role of dwelling time (at fixed temperature) on the nanostructure of grains. Experimental observations are mainly based on XRD and SEM analyses.

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Nanostructured sol–gel silica thin films doped with NiO and SnO2for gas sensing applications

Journal of Materials Chemistry ◽

10.1039/b405301j ◽

2004 ◽

Vol 14 (19) ◽

pp. 2889-2895 ◽

Cited By ~ 38

Author(s):

Alessandro Martucci ◽

Dario Buso ◽

Matthias De Monte ◽

Massimo Guglielmi ◽

Carlo Cantalini ◽

...

Keyword(s):

Thin Films ◽

Gas Sensing ◽

Sol Gel ◽

Sensing Applications ◽

Silica Thin Films

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Effect of Deposition Time on Structural and Optoelectronic Properties of Flower-Like Nanostructured PbS Thin Films

Journal of Scientific Research ◽

10.3329/jsr.v13i1.47240 ◽

2021 ◽

Vol 13 (1) ◽

pp. 9-20

Author(s):

N. H. Sheeba ◽

A. Namitha ◽

K. M. Ramsiya ◽

T. M. Ashitha ◽

R. Suhail

Keyword(s):

Thin Films ◽

Deposition Time ◽

Gas Sensing ◽

Soda Lime ◽

Soda Lime Glass ◽

Sem Images ◽

Glass Substrates ◽

Sensing Applications ◽

Vis Spectroscopy ◽

Two Peaks

Polycrystalline nanostructured PbS thin ﬁlms are deposited onto soda-lime glass substrates by the method of chemical bath deposition (CBD) at different duration of deposition time. The structure and surface morphology of the ﬁlms are characterized by X-ray diﬀraction (XRD) and field effect scanning electron microscopy (FE-SEM). XRD pattern exhibits polycrystalline structure with preferential orientation along (200) direction, parameters such as crystallite size, lattice constant, lattice-strain and dislocation density are calculated. The FE-SEM images show appearance of flower like structure on formation of PbS films which is indicative of suitability in gas sensing applications. Studies on optical properties carried out by UV-Vis spectroscopy measurements show bandgap in the range 1.65eV – 1.41eV. The photoluminescence spectra of the films exhibit two peaks centered at around 613 nm and 738 nm after excitation at 450 nm. Electrical studies from Hall measurements indicate the carrier concentration and mobility of the PbS samples corroborate the variations in the conductivity.

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Synthesis of TiO2 Thin Films Nanoparticles with Different Layers using Simple Sol-Gel Method

Iraqi Journal of Science ◽

10.24996/ijs.2021.62.11(si).23 ◽

2021 ◽

pp. 4425-4429

Author(s):

Rajaa Obayes Abdulsada ◽

Thamir A.A. Hassan

Keyword(s):

Thin Films ◽

Solar Cell ◽

Spin Coating ◽

Sol Gel ◽

Flat Glass ◽

Morphological Properties ◽

Tio2 Thin Films ◽

Simple Method ◽

Glass Substrates ◽

Tio2 Gel

In this study, titanium dioxide (TiO2 (are synthesized by sol– gel simple method. Thin films of sol, gel, and sol- gel on relatively flat glass substrates are applied with Spin coating technique with multilayers. The optical and morphological properties (studied using AFM) of TiO2 layers show good properties, with particles diameters less than 4 nm for all prepared samples and have maximum length 62 nm for TiO2 gel thin films of three layers. The results show low roughness values for all films especially for 4 layers sol (8.37nm), which improve the application in dye sensitive solar cell (DSSc) .

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STRUCTURE AND DIELECTRIC PROPERTIES OF La-DOPED LEAD STRONTIUM TITANATE THIN FILMS DERIVED FROM SOL–GEL METHOD

Surface Review and Letters ◽

10.1142/s0218625x08010877 ◽

2008 ◽

Vol 15 (01n02) ◽

pp. 13-18

Author(s):

X. T. LI ◽

C. WU ◽

W. J. WENG ◽

G. R. HAN ◽

P. Y. DU

Keyword(s):

Thin Films ◽

Dielectric Properties ◽

Perovskite Phase ◽

Sol Gel ◽

Dielectric Constants ◽

X Ray Diffraction ◽

Glass Substrates ◽

Ito Glass ◽

Gel Technique ◽

La Doped

A series of ( Pb 0.4 Sr 0.6)1-x La 2x/3 TiO 3 (PSLT) thin films were deposited on ITO/glass substrates by sol–gel technique. Their phase status, surface morphology, and dielectric properties were studied by X-ray diffraction, scanning electron microscope, and impedance analyzer, respectively. Results show that the PSLT thin films were consisted of tetragonal perovskite phase PSLT thin films for x < 0.4, and cubic perovskite phase PSLT thin films for x > 0.4. Dielectric properties such as dielectric constants, dielectric tunabilitis, and inharmonic coefficient were characterized as a function of the film composition.

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