Electronic nose for detection of toxic volatile organic compounds in air

We demonstrate a general approach using novel thiols to functionalize gold nanoparticles for fabricating gas sensors to detect toxic volatile organic compounds (VOCs) in air. Poor selectivity and low sensitivity are common challenges for chemiresistor-based gas sensors. Gold nanoparticle-based gas sensors have the advantage of accommodating thiols for surface modification. The designed thiols with a molecular recognition motif for interaction with target analytes dramatically increase both selectivity and sensitivity of the sensors. The sensors showed a linear response relationship in a broad vapor concentration range from 0.1 ppb to 1000 ppm for various VOCs. A sensor array of the thiol functionalized gold nanoparticles enables analysis of target VOCs.