A Survey on Gas Sensing Technology

TLDR

Gas sensing technology is widely used for detection, yet differing applicability and inherent limitations drive research into scenario‑specific calibration improvements. This paper reviews and compares existing gas sensing technologies, emphasizing sensitivity and selectivity and proposing approaches to enhance these performance indicators. The review classifies technologies by electrical and other property variations, detailing electrical‑based methods (metal‑oxide semiconductors, polymers, carbon nanotubes, moisture‑absorbing materials) and optical, calorimetric, acoustic, and gas‑chromatographic methods, and outlines future development suggestions.

Abstract

Sensing technology has been widely investigated and utilized for gas detection. Due to the different applicability and inherent limitations of different gas sensing technologies, researchers have been working on different scenarios with enhanced gas sensor calibration. This paper reviews the descriptions, evaluation, comparison and recent developments in existing gas sensing technologies. A classification of sensing technologies is given, based on the variation of electrical and other properties. Detailed introduction to sensing methods based on electrical variation is discussed through further classification according to sensing materials, including metal oxide semiconductors, polymers, carbon nanotubes, and moisture absorbing materials. Methods based on other kinds of variations such as optical, calorimetric, acoustic and gas-chromatographic, are presented in a general way. Several suggestions related to future development are also discussed. Furthermore, this paper focuses on sensitivity and selectivity for performance indicators to compare different sensing technologies, analyzes the factors that influence these two indicators, and lists several corresponding improved approaches.