Detection and discrimination of pure gases and binary mixtures using a dual-modality microcantilever sensor

A new method for detecting and discriminating pure gases and binary mixtures has been investigated. This approach is based on two distinct physical mechanisms which can be simultaneously employed within a single microcantilever: heat dissipation and resonant damping in the viscous regime. An experimental study of the heat dissipation mechanism indicates that the sensor response is directly correlated to the thermal conductivity of the gaseous analyte. A theoretical data set of resonant damping was generated corresponding to the gas mixtures examined in the thermal response experiments. The combination of the thermal and resonant response data yields more distinct analyte signatures that cannot otherwise be obtained from the detection modes individually.