A fiber optic gas sensor with a PMMA fiber whose clad is modified with chemically sensitive nano-crystalline zinc oxide has been developed and investigated to detect acetone, isopropyl alcohol and benzene gases. The spectral characteristics of the sensor were recorded for different concentrations ranging from (0-500 ppm) for these gases both with as-prepared and annealed nanocrystalline ZnO, and the influence of annealing on the gas sensing has been studied.The response time and recovery time were found to be 48 min. and 42 min. respectively for 500 ppm concentration. © 2013 Elsevier Inc. All rights reserved.

Angarai Ramanathan Ganesan

Department Of Physics

Balusamy Renganathan

Acetone

Chemical detection

Chemical sensors

Fiber optics

Fibers

GAS DETECTORS

Gas sensing electrodes

II-VI semiconductors

Nanocrystals

Zinc oxide

GAS SENSING MECHANISM

Isopropyl alcohols

NANOCRYSTALLINE ZNO

Nanocrystallines

OPTIC GAS SENSOR

recovery time

Spectral characteristics

TOXIC GAS

Gases

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Optical Fiber Technology

The promising radiation technology was inculcated for the enhancement of gas sensing performance of fibre optic gas sensor. Magnesium tetraborate (MTB), known for its radiation dosimetry and frequency conversion application was used as a sensor element. Solid state sintering technique was adopted for the preparation of polycrystalline samples. In order to understand the role of crystallinity in gas sensing property, the glasses of magnesium tetraborate was synthesize by following melting-quenching method. Cerium (Ce) was doped with MTB in 0.25 mol% concentration. XRD pattern reveals the perfect incorporation of dopant without changing the crystal structure of the host and the cell parameters are matches well with standard ICDD data (031-0787). UV–Vis absorption spectra show the lack of any strong absorption in visible region. Irrespective of crystalline nature, the gas sensitivity of pristine MTB is highly negligible say, 2 counts/50 ppm and 1 counts/50 ppm respectively. Interestingly, gamma radiation treated MTB:Ce samples shows excellent sensitivity of 35 counts/50 ppm and 46 counts/50 ppm towards acetone vapours. Based on the obtained results, gamma irradiated cerium doped MTB glass is suggested as a best sensor for the detection of acetone with high sensitivity. © 2019 Elsevier Inc.

Gamma radiation impact on the fiber optic acetone gas sensing behaviour of magnesium tetraborate

Nanocrystalline copper bromide (γ-CuBr) has been synthesized by hydrothermal method. The as-synthesized sample was characterized for its structural and microstructural properties using powder X-ray diffraction, electron diffraction and high resolution transmission electron microscope. The surface characteristics and optical properties of the sample were further studied with spectroscopy techniques such as FT-IR transmittance, diffused reflectance and fluorescence. Further, γ-CuBr nanocrystals was used as a gas sensing material in clad-modified optical fiber gas sensing system to explore its sensing behaviour for acetone (C3H6O), ammonia (NH3) and ethanol (C2H5OH). As compared with other gases, γ-CuBr nanocrystals showed superior sensitivity and specificity to acetone gas. The mechanism involved in the present, clad-modified optical fiber acetone sensor was discussed in detail. © 2018

Materials Science in Semiconductor Processing

Acetone sensing behaviour of optical fiber clad-modified with γ-CuBr nanocrystals

A clad modified optical fiber gas sensor for sensing volatile organic compound vapours (VOCs) such as formaldehyde (HCHO), ammonia (NH3), ethanol (C2H5OH) and methanol (CH3OH) up to 500 ppm was studied using nanocrystalline nickel oxide embedded coatings. Prior to the measurements, nickel oxide in two different crystallite sizes such as 24 nm and 76 nm was synthesized by calcination of reverse precipitated nickel hydroxide subsequently at 450 °C and 900 °C for 30 min. Then, samples physical properties were characterized using X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM). Our gas sensing measurement concludes that the lower crystallite size (24 nm) nickel oxide nanocrystals exhibits superior performance to formaldehyde and ethanol vapours as compared with other two VOCs, the observed experimental results were discussed in detail. © 2017 Elsevier Inc.

Clad modified optical fiber gas sensors based on nanocrystalline nickel oxide embedded coatings

Sensors and Actuators B: Chemical

Gas sensing properties of a clad modified fiber optic sensor with Ce, Li and Al doped nanocrystalline zinc oxides

The Journal of Physical Chemistry C

Embossed TiO2 Thin Films with Tailored Links between Hollow Hemispheres: Synthesis and Gas-Sensing Properties

Mechanism Study of ZnO Nanorod-Bundle Sensors for H2S Gas Sensing

Nanotechnology

SnO2nanotubes fabricated using electrospinning and atomic layer deposition and their gas sensing performance

Optical sensing of ammonia using ZnO nanostructure grown on a side-polished optical-fiber

Fiber optic gas sensor with nanocrystalline ZnO

Journal	Optical Fiber Technology
Publisher	Academic Press Inc.
ISSN	10685200
Open Access	No