Specific Odor Coding Using a Single Thin-Film Transistor

The specificity of olfactory receptor cells (ORCs) in the human nose is the physiological basis for their powerful odor coding capacity. Ideally, artificial ORCs in bioinspired machine olfaction represented by electronic noses (e-noses) should have a desirable specificity. However, mapping gas-solid interactions at the ORC level for specific odor perception remains a key challenge because of the cross-sensitivity issues of gas sensors in e-noses. Here, we use a thin-film transistor (TFT) to generate a two-dimensional matrix code by resolving the electronic transduction process (chemical reception and electron transduction) arising from the gas-solid interactions. As a proof-of-concept experiment, we selected lead sulfide quantum dots and black phosphorus as sensitive materials and achieved specific discrimination between typical oxidizing gases. The developed coding method has physical interpretability, enabling its extension to other gas-sensitive materials and target analytes.