Ag Additive and Nanorod Structure Enhanced Gas Sensing Properties of Metal Oxide-Based CO2 Sensor

Carbon dioxide (CO
₂
) gas sensor with a silver additive and nanorod structure is studied. The tandem p-i-n diodes with the silver additive are fabricated on silicon nanorods substrate. Nanorod structure provides a higher surface-to-volume ratio and more surface area for sensing reaction. The Ag additive modulates the sensing material characteristics and leads the developed device to have a high response of 2185% to 3000 ppm CO
₂
gas. The tandem p-i-n diodes have superior characteristics to CO
₂
gas including fast response time. Combining the two features of device fabrication, the sensor has potential for high-performance CO
₂
sensing applications.