(286d) CNT-Based Carbon Monoxide Sensors with Voltage-Modulated Sensitivity

CNT-based
Carbon Monoxide Sensors with Voltage-modulated Sensitivity 

Suchol
Savagatrup, Vera Schroeder, and Timothy M. Swager

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 this strong and specific interaction between the CO and
heme-inspired iron porphyrin provides promises for highly selective and
customizable sensors that are viable
alternatives to technologies based on mass spectroscopy and optical detection
systems. In this presentation, we report the development of CNT-based
sensors for the detection of CO with voltage-modulated sensitivity comprising
iron porphyrin and functionalized single-walled CNTs, Figure 1. Modulation of
the gate voltage led to that the in situ
reduction of Fe³⁺ to Fe²⁺ enhances the interaction
between the decorated CNTs and CO, leading to the significant increase in the
signal strength when negative gate voltage is applied. UV-Vis, differential
pulse voltammetry, and computational studies confirmed our sensing data.
Furthermore, the sensors are selective to ppm levels of CO and functional in
air. Our results provide a step toward
the development of a novel platform of voltage-activated sensors based on
highly specific chemical interactions.