Enhancement of carbon dioxide sensitivity by silver additive and nanorod structure

The Pd/SnO₂/Al₂O₃/CuO/Ag/SnO₂/Al₂O₃/CuO/p-Si/Al tandem p-i-n diodes with nanorod structure and addition of silver interconnecting metal layer were studied. The added interconnecting metal layer influences the material characteristics and leads the developed device to have a high relative sensitivity ratio of ~2185% to 3000 ppm CO₂ ambient gas. The response time of 20 sec is also fast. Thus, it has a potential for high performance CO₂ sensing applications.