Room temperature CO2 detection using interdigitated capacitors with heteropolysiloxane sensing films

This paper investigates the detection of carbon dioxide at room temperature using microfabricated, interdigitated capacitive (IDC) sensors coated with an amino-functionalized sensing film. Sensing experiments performed at temperatures ranging from room temperature to 100°C indicate two different temperature-dependent sensing mechanisms. Around room temperature, physisorption dominates the sensor response, resulting in fast signal transients and negative capacitance changes. Above 80°C, chemisorption appears to dominate, resulting in larger, positive capacitance changes with longer signal transients.