Abstract
Carbon monoxide (CO) outcompetes oxygen when binding to the iron center of hemeproteins, leading to a reduction in blood oxygen level and acute poisoning. Harvesting the strong specific interaction between CO and the iron porphyrin provides a highly selective and customizable sensor. We report the development of chemiresistive sensors with voltage-activated sensitivity for the detection of CO comprising iron porphyrin and functionalized single-walled carbon nanotubes (F-SWCNTs). Modulation of the gate voltage offers a predicted extra dimension for sensing. Specifically, the sensors show a significant increase in sensitivity toward CO when negative gate voltage is applied. The dosimetric sensors are selective to ppm levels of CO and functional in air. UV/Vis spectroscopy, differential pulse voltammetry, and density functional theory reveal that the in situ reduction of FeIII to FeII enhances the interaction between the F-SWCNTs and CO. Our results illustrate a new mode of sensors wherein redox active recognition units are voltage-activated to give enhanced and highly specific responses.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 14066-14070 |
| Number of pages | 5 |
| Journal | Angewandte Chemie International Edition |
| Volume | 56 |
| Issue number | 45 |
| DOIs | |
| State | Published - Oct 4 2017 |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledged KAUST grant number(s): CRF-2015-SENSORS-2719
Acknowledgements: This work was supported by the KAUST sensor project CRF-2015-SENSORS-2719 and the Army Research Office through the Institute for Soldier Nanotechnologies and the National Science Foundation (DMR-1410718). S.L. was supported by an F32 Ruth L. Kirschstein National Research Service Award. M.H. was supported by NIH Training Grant T32ES007020. We thank Dr. Lionel Moh for the designs of the substrates for our sensors and Dr. Joseph Walish for fabricating the gas enclosures.