A clad-modified fiber optic sensor with nanocrystalline CeO2 is proposed for gas detection. As-prepared and annealed CeO2 (500 C) samples have been used as gas sensing media. The spectral characteristics of the fiber optic gas sensor are studied for various concentrations of ammonia, ethanol and methanol gases (0-500 ppm). The sensor exhibits linear variation in the spectral peak intensity with the gas concentration. The characteristics of the sensor are also studied for gas selectivity. The time response characteristics of the sensor are reported. © 2013 Elsevier B.V. All rights reserved.

Angarai Ramanathan Ganesan

Department Of Physics

Balusamy Renganathan

AMMONIA GAS

ANNEALED CEO2

Gas concentration

LINEAR VARIATION

NANOCRYSTALLINE CERIUM OXIDES

Nanocrystallines

Response characteristic

Spectral characteristics

Ammonia

Fiber optic sensors

Sensors

GAS DETECTORS

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

Current Applied Physics

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

The design of fiber optic sensor is based on a cladding modification methodology. A fiber-optic chemical sensor is developed by replacing a certain portion of the original cladding with a chemically sensitive material, specifically, calcinated gadolinium oxide (Gd2O3).Both the light absorption co-efficient and refractive index change upon exposure to chemical vapours of volatile organic compounds (VOCs) such as ammonia (NH3), ethanol (CH3CH2OH), and methanol (CH3OH). The spectral characteristics of the sensor were studied for different concentrations ranging from 0-500 ppm. These changes induced the optical intensity modulation of the transmitted optical signal. During interaction between the sensing material and VOCs, the output intensity is taken into account to detect the toxic VOCs present in the environment. This was systematically investigated by X-ray diffractometer (XRD) and SEM. The XRD analysis indicated that the calcinated Gd2O3 was formed in cubic structure with the crystallite size of 13 nm. The Gd2O3 nanorods with thickness ranging from 80 to 120 nm were confirmed from SEM. The ammonia gas response of the Gd2O3 sensor is presented. A model is proposed for understanding the spectral intensity variations. © 2017 Author(s).

AIP Conference Proceedings

Ammonia gas sensing property of gadolinium oxide using fiber optic gas sensor

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.

Optical Fiber Technology

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

Purpose: This paper aims to focus on research work related to metamaterial-based sensors for material characterization that have been developed for past ten years. A decade of research on metamaterial for sensing application has led to the advancement of compact and improved sensors. Design/methodology/approach: In this study, relevant research papers on metamaterial sensors for material characterization published in reputed journals during the period 2007-2018 were reviewed, particularly focusing on shape, size and nature of materials characterized. Each sensor with its design and performance parameters have been summarized and discussed here. Findings: As metamaterial structures are excited by electromagnetic wave interaction, sensing application throughout electromagnetic spectrum is possible. Recent advancement in fabrication techniques and improvement in metamaterial structures have led to the development of compact, label free and reversible sensors with high sensitivity. Originality/value: The paper provides useful information on the development of metamaterial sensors for material characterization. © 2018, Emerald Publishing Limited.

Sensor Review

A review: metamaterial sensors for material characterization

Optics & Laser Technology

Nanocrystalline ZnO coated fiber optic sensor for ammonia gas detection

IEEE Sensors Journal

Thickness Dependency of Thin-Film Samaria-Doped Ceria for Oxygen Sensing

Sensors and Actuators B: Chemical

Highly sensitive and selective butanone sensors based on cerium-doped SnO2 thin films

Journal of Alloys and Compounds

Changes in the structural and optical properties of CeO2 nanocrystalline films: Effect of film thickness

Optics and Lasers in Engineering

Optical fiber Bragg grating hydrogen sensor based on evanescent-field interaction with palladium thin-film transducer

Nanocrystalline cerium oxide coated fiber optic gas sensor

Journal	Current Applied Physics
ISSN	15671739
Open Access	No