Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : gas sensor


Manufacturing of Bi-functional Nano-sensor of Nobel Metal for Hydrocarbon Gas Detection in Petroleum Sector Using Pulse Laser Deposition Technique

K.A. Sukkar; S.M. Kadhim; A.S. Falih

Engineering and Technology Journal, 2017, Volume 35, Issue 8, Pages 864-871

In the present investigation bi-functional nano-gas-sensor was manufactured from two types of metals: ZnO metal oxide and Pt noble metal. The nano-gas-sensors were designed for monitoring and control the environmental pollution in petroleum sector. The preparation technique was carried out by design and construction of a pulse laser deposition unit (PLD) with Nd: YAG laser (λ=532nm, laser fluence 2 J/cm2, repetition rate 6 Hz and the pulse duration 7ns). The target was pure ZnO and Pt:ZnO that containing 4%wt Pt. The hexachloroplatinic acid (H2PtCl6) was used as Pt source. The PLD films were deposited at three different temperatures 200, 250, and 300oC. Many characterization tests are used to study the influence of temperature on surface morphology of prepared films: Scanning Electron Microscope (SEM), Atomic Force Microscope (AFM), x-ray Diffraction (XRD) and (UV) visible. The results pointed to a direct relationship between the deposition temperature and the grain sizes of the nanoparticles formed on the substrate. On the other hand, the results of RMS roughness of AFM showed an increased value with increasing of deposition temperature. The best value of RMS roughness was 10.3nm for thin films deposited at 250ºC. The x-ray results shows formation of nanostructure on the substrate at deposition temperature of 250ºC, in which represent high surface area of gas sensor and especially with Pt. In addition, the UV-VIS transmittance measurements have shown that the films are highly transparent in the Visb-NIR wavelength region, with an average transmittance of about 90%. These results pointed to that the manufactured bi-metals nano-gas-sensor (Pt:ZnO) at 250oC is more suitable for LPG hydrocarbons detection application in petroleum positions.

Study of ZnO, SnO2 and Compounds ZTO Structures Synthesized for Gas-Detection

Farhad M. Othman; Alaa A. Abdul-Hamead; Alaa S. Taeeh

Engineering and Technology Journal, 2015, Volume 33, Issue 6, Pages 1328-1340

Semiconductor-based metal oxide gas detector of five mixed Z:S from zinc chloride salt (0,25,50,75,100%) ratios with tin chloride salt, were fabricated on glass substrate by a spray pyrolysis technique with thickness were about ( 0.2 ±0.05 µm) using water soluble as precursors at a substrate temperature 500 Cº±5, 0.05 M ,and their gas sensing properties toward (CO2 , NO2 and SO2 gas at different concentration (10,100,1000 ppm) in air were investigated at room temperature which related with the petroleum industry.
Furthermore structural and morphology properties was inspecting. Experimental results show that the mixing ratio affect the composition of formative oxides (ZnO,Zn2SnO4,Zn2SnO4+ZnSnO3,ZnSnO3, SnO2) ratios mentioned in the above respectively, and related with the sensitivity of the tested oxidation gases.

Hydrogen Gas Sensor of ZnO Doping with CuO/PS Nanocomposite

Isam M. Ibrahim; Shahad I.sharhan; Fuad T.ibrahim

Engineering and Technology Journal, 2015, Volume 33, Issue 6, Pages 1093-1101

Pulse laser deposition was used in this research by Nd:YAG laser with (λ=1064 nm average frequency 6 Hz and pulls duration 10 nm) to deposit an adopedZnO thin films with 0.02CuO with thickness (100) nm. X-ray diffraction pattern for Zinc oxide films with doping ratio of CuO shows that these films have polycrystalline hexagonal structure, and the X-ray diffraction patterns of porous silicon showed a broadening in the FHWM with increasing etching time. .From atomic force microscope of prepared samples show an average diameter of PS nanostructure. The operation temperature of gas sensor was studied for different temperature and found that the maximum sensitivity is (67.55) at T=350 cº.

Development of NO2 gas sensor using Sn-doped ITO nanoparticles prepared by Sol-Gel method

Saryia D. Al-ALgawi; Rashed T. Rasheed; Sahar Zeyad Tareq

Engineering and Technology Journal, 2015, Volume 33, Issue 6, Pages 984-993

In this work In2O3 and Sn-doped ITO nanoparticles were prepared by sol-gel method and deposited on quartz substrate by dip coating technique at different doping concentration of (5, 10 and 15%). The samples were annealed at 550 oC at constant time (60 min). X-ray analysis confirmed the formation of polycrystalline cubic phase that decreases in crystalline size with increasing doping concentration. The optical properties of Sn-ITO nanostructure thin film were studied. The transmittance was measured in the wavelength range of (300nm to 1100 nm) for all thin films. The sensitivity towards NO2 gas was measured, when In2O3 was doped with Sn at different concentrations.

Fabrication and Characterization of ZnO Gas Sensor

Alaa A. Abdul-Hamead; Farhad M. Osman; Alaa S. Taeeh

Engineering and Technology Journal, 2014, Volume 32, Issue 9, Pages 2303-2312

In this paper thin films of zinc oxide ZnO was prepared by spray pyrolyess method with thickness were about ( 0.1 ±0.05 µm) on n-type silicon substrates at different deposition temperature (300,400,500) C°, from zinc chloride at concentrations (0.05,0.1) M as a sensor for pollutant gases like CO2 , NO2, and H2S related with oil manufacture .
The crystallinity and morphology of the films were characterized by XRD, and optical microscopy was done on prepared films , addition to sensitivity to polluting gases previously mentioned at different test temperature (10-50) C°.
Result shows that the crystallization increased by increasing deposition temperature(substrate temperature), and the sensitivity increased by rising both of the gas concentration or temperature.

Study of Some Properties of SnO2 Thin Film

Alaa A. Abdul-Hamead

Engineering and Technology Journal, 2013, Volume 31, Issue 12, Pages 2292-2298

In this paper thin films of Tin oxide SnO2 was prepared by spray pyrolyess method
on glass and pure silicon substrates at deposition temperature(300,400,500) Cᵒ, from Tin
chloride at concentration(0.1 M) .
The films thickness were about 0.1 ±0.02 μm and Atomization rate was about
(1 nm/s).
The test was done on prepared film by XRD and optical microscopy addition to
sensitivity to nitrous oxide gas at different test temperature (25, 50, 75,100) Cᵒ.
Result shows that the crystallization increased by increasing deposing temperature
and the sensitivity increased by rising the gas concentration or temperature.

Organic Vapors Sensor Based on Dangling Bonds of Porous Silicon

Alwan M. Alwan

Engineering and Technology Journal, 2007, Volume 25, Issue 8, Pages 1023-1027

In this paper, a porous silicon (PS) layer is investigated as a sensing material
to detect the organic vapors with low concentration. The structure of the
prepared sensor consists of thin Au /PS/n-Si/Au thick where the PS is etched
photo -chemically. The current response of the sensor is governed by the
partial depletion of silicon located between two adjacent (porous
regions).This depletion is due to the charges trapped on dangling bonds
associated with the silicon – porous silicon interface .