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Article
Publication date: 25 January 2011

Jacob Y. Wong and Mike Schell

Output stability or drift overtime has long been a major performance deficiency for gas sensors irrespective of what technology or methodology is used for their…

Abstract

Purpose

Output stability or drift overtime has long been a major performance deficiency for gas sensors irrespective of what technology or methodology is used for their conception. Software correction may alleviate the problem somewhat but it is not always applicable. It has long been the objective of many researchers in this field to overcome this problem fundamentally and for good. The purpose of this paper is to show that this objective has now finally been achieved.

Design/methodology/approach

Conventional non‐dispersive infrared (NDIR) dual beam methodology utilizes the ratio of signal channel output over reference channel output for signal processing. The signal filter overlaps the absorption band of the gas of interest while the reference filter does not. However, this ratio changes as the source ages. The current methodology uses an absorption bias between signal and reference channel outputs. This absorption bias is created by using a path length for the signal channel greater than that for the reference channel. Both the signal and reference detectors carry an identical spectral filter overlapping the absorption band of the gas to be measured.

Findings

Implementation of the currently patented NDIR gas‐sensing methodology has been carried out in different gas sensor configurations for over a year in the laboratory. Performance results for these sensors showing insignificant output drifts overtime have been repeatedly demonstrated via simulated aging for the source.

Originality/value

The paper puts forward the view that the recent breakthrough of the Near Zero Drift methodology for NDIR gas sensors will very quickly change the hierarchy of technology dominance and utility for gas sensors at large.

Details

Sensor Review, vol. 31 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 3 November 2020

Chinmay Roy, Aparna Ghosh and Suman Chatterjee

This paper aims to estimate the relationship between defect structure with gas concentration for use as a gas sensor. The change in defect concentration caused a shift in…

Abstract

Purpose

This paper aims to estimate the relationship between defect structure with gas concentration for use as a gas sensor. The change in defect concentration caused a shift in the Fermi level, which in turn changed the surface potential, which is manifested as the potentiometric response of the sensing element.

Design/methodology/approach

A new theoretical concept based on defect chemistry and band structure was used to explain the experimental gas response of a sensor. The theoretically simulated response was compared with experimental results.

Findings

Understanding the origin of potentiometric response, through the generation of defects and a corresponding shift in Fermi level of sensing surface, by the adsorption of gas. Through this understanding, the design of a sensor with improved selectivity and stability to a gas can be achieved by the study of defect structure and subsequent band analysis.

Research limitations/implications

This paper provides information about various types of surface defects and numerical simulation of material with defect structure. The Fermi energy of the simulated value is correlated with the potentiometric sensor response.

Practical implications

Gas sensors are an integral part of vehicular and industrial pollution control. The theory developed shows the origin of response which can help in identifying the best sensing material and its optimum temperature of operation.

Social implications

Low-cost, reliable and highly sensitive gas sensors are highly demanded which is fulfilled by potentiometric sensors.

Originality/value

The operating principle of potentiometric sensors is analyzed through electron band structure analysis. With the change in measured gas concentration, the oxygen partial pressure changes. This results in a change in defect concentration in the sensing surface. Band structure analysis shows that change in defect concentration is associated with a shift in Fermi level. This is the origin of the potentiometric response.

Details

Sensor Review, vol. 40 no. 6
Type: Research Article
ISSN: 0260-2288

Keywords

Content available
Article
Publication date: 1 December 2004

Jon Rigelsford

68

Abstract

Details

Sensor Review, vol. 24 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

Content available
Article
Publication date: 1 December 1999

39

Abstract

Details

Facilities, vol. 17 no. 12/13
Type: Research Article
ISSN: 0263-2772

Keywords

Article
Publication date: 15 September 2021

Srinivas Rao Sriram, Saidireddy Parne, Venkata Satya Chidambara Swamy Vaddadi, Damodar Edla, Nagaraju P., Raji Reddy Avala, Vijayakumar Yelsani and Uday Bhasker Sontu

This paper aims to focus on the basic principle of WO3 gas sensors to achieve high gas-sensing performance with good stability and repeatability. Metal oxide-based gas

Abstract

Purpose

This paper aims to focus on the basic principle of WO3 gas sensors to achieve high gas-sensing performance with good stability and repeatability. Metal oxide-based gas sensors are widely used for monitoring toxic gas leakages in the environment, industries and households. For better livelihood and a healthy environment, it is extremely helpful to have sensors with higher accuracy and improved sensing features.

Design/methodology/approach

In the present review, the authors focus on recent synthesis methods of WO3-based gas sensors to enhance sensing features towards toxic gases.

Findings

This work has proved that the synthesis method led to provide different morphologies of nanostructured WO3-based material in turn to improve gas sensing performance along with its sensing mechanism.

Originality/value

In this work, the authors reviewed challenges and possibilities associated with the nanostructured WO3-based gas sensors to trace toxic gases such as ammonia, H2S and NO2 for future research.

Details

Sensor Review, vol. 41 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 1 February 1989

D.J. Mobbs and D. Summerhayes

Sensor Review publishes the results of a major sensor survey.

Abstract

Sensor Review publishes the results of a major sensor survey.

Details

Sensor Review, vol. 9 no. 2
Type: Research Article
ISSN: 0260-2288

Article
Publication date: 1 June 2000

George K. Chako

Briefly reviews previous literature by the author before presenting an original 12 step system integration protocol designed to ensure the success of companies or…

6001

Abstract

Briefly reviews previous literature by the author before presenting an original 12 step system integration protocol designed to ensure the success of companies or countries in their efforts to develop and market new products. Looks at the issues from different strategic levels such as corporate, international, military and economic. Presents 31 case studies, including the success of Japan in microchips to the failure of Xerox to sell its invention of the Alto personal computer 3 years before Apple: from the success in DNA and Superconductor research to the success of Sunbeam in inventing and marketing food processors: and from the daring invention and production of atomic energy for survival to the successes of sewing machine inventor Howe in co‐operating on patents to compete in markets. Includes 306 questions and answers in order to qualify concepts introduced.

Details

Asia Pacific Journal of Marketing and Logistics, vol. 12 no. 2/3
Type: Research Article
ISSN: 1355-5855

Keywords

Article
Publication date: 1 February 1991

Peter McGeehin

Introduction Optical sensors, and especially fibre optic sensors, offer some significant technical advantages over conventional electronic sensors. These technical…

Abstract

Introduction Optical sensors, and especially fibre optic sensors, offer some significant technical advantages over conventional electronic sensors. These technical advantages have been perceived to be sufficiently significant to have stimulated a large amount of research activity in the UK and elsewhere. Much of the original research has been carried out in universities and polytechnics, but there has also been considerable corporate R&D activity aimed at developing commercial products and systems. The results of much of this corporate work have not been published, except in the form of patents. Patents therefore provide a useful literature which, though of considerable interest to companies, is difficult to analyse and assimilate. For this reason, the DTI Advanced Sensors Technology Transfer Programme commissioned a study of recent optical sensor patents. The aim was to classify and analyse the patents, and to present the findings in a manner which a small or medium size instrumentation company could readily digest.

Details

Sensor Review, vol. 11 no. 2
Type: Research Article
ISSN: 0260-2288

Content available
Article
Publication date: 25 January 2011

43

Abstract

Details

Sensor Review, vol. 31 no. 1
Type: Research Article
ISSN: 0260-2288

Article
Publication date: 1 January 1990

The Japanese show no dimunition of their inventive skills in the sensor technology area, as Stephen McClelland reports.

Abstract

The Japanese show no dimunition of their inventive skills in the sensor technology area, as Stephen McClelland reports.

Details

Sensor Review, vol. 10 no. 1
Type: Research Article
ISSN: 0260-2288

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