Dual-channel sensing of volatile organic compounds with semiconducting nanoparticles

Extracting multidimensional information from an individual transducer simultaneously is a promising alternative sensing strategy to traditional sensors. Here, we proposed a novel dual channel sensing method with simultaneously recording conductivity change of sensing material and chemiluminescence emission during catalytic oxidation of volatile organic compounds on tin oxide nanoparticles. The orthogonal and complementary electrical and optical signals have been obtained for each compound, which have been applied to discriminate 20 volatile organic compounds using hierarchical cluster analysis (HCA). Unknown samples from three groups at concentrations of 0.2%, 0.6%, and 1.0% have been successfully classified using linear discriminant analysis (LDA) with accuracies of 98.3%, 96.7%, and 98.3%, respectively. This dual channel sensing mode is a complement of semiconducting type gas sensors and quite promising for the development of chemical sensor arrays with multimode transducing principles.