Bio‐Inspired Carbon Monoxide Sensors with Voltage‐Activated Sensitivity. Issue 45 (4th October 2017)

• Record Type: Journal Article
• Authors: Savagatrup, Suchol; Schroeder, Vera; He, Xin; Lin, Sibo; He, Maggie; Yassine, Omar; Salama, Khaled N.; Zhang, Xi‐Xiang; Swager, Timothy M.
• Is Part Of: Angewandte Chemie international edition. Volume 56:Issue 45(2017)
• Page Start: 14066
• Page End: 14070
• Publication Date: 2017-10-04
• Subjects: Carbon monoxide -- carbon nanotubes -- iron porphyrin -- sensors -- voltage-activated; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201707491
• Languages: English
• ISSNs: 1433-7851

Abstract

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 Fe III to Fe II 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. Abstract : Revving up for sensing : A platform for voltage‐activated, chemiresistive gas detection has been delveloped based on covalently functionalized single‐walled carbon nanotubes decorated with voltage‐responsive chemical selectors. The sensor is highly selective towards CO in the presence of oxygen, nitrogen, and carbon dioxide and is robust to humidity and remains operational in air.