High sensitivity semiconductor gas sensors

This paper is a review article on high sensitivity gas sensors using semiconductor oxides in past decade. The target gases include air pollutants, bad-smelling gases, and VOCs, which exist in very low concentration (ppb-level) and are needed to be detected with high sensitivity for the purpose of mainly environmental monitoring and protection. Particularly, the design of highly selective gas sensor by using unique receptor and the nano-design of electrode structure for high sensitivity gas sensors are introduced in detail. Finally, the new application fields of such high sensitivity gas sensors are proposed for welfare and medical fields in future.