Microfabricated and Nanoengineered Chemical Sensors for Air Quality Monitoring System

Abstract

The importance of air quality monitoring is rapidly increasing. Although state-of-the-art air quality monitoring systems based on sophisticated optical systems or gas chromatography provide high accuracy measurement of air quality parameters, they cannot provide highly portable and/or personalized platform due to high cost, difficult maintenance and poor portability. With the advent of mobile electronic systems such as smartphones or wearable gadgets, people are more interested in obtaining personalized and highly localized environmental information rather than averaged and global information. To meet this need, highly integrated, ultra-compact, and low-power gas sensors that can be put into small electronic systems should be developed. The best approach to enable this is to use microfabricated (i.e., MEMS) sensing platform and nanoengineered sensing materials. In this chapter, we review the design and fabrication MEMS-based gas sensors and their applications to portable air quality monitoring. In addition, the principles, designs and the usage of functional nanomaterials to highly sensitive, highly selective and quickly responding air quality sensors are explained. Finally, we explain our recent development on the controlled synthesis of nanomaterials on microfabricated platform and its application to advanced gas sensing devices.