CNT Polymer Composite IR Sensors

Levitsky and co-workers have investigated isotropic and anisotropic SWNT-polystyrene composites, respectively, for mid-IR (2.5-20 pm) sensing applications. They have demonstrated that the composite alignment in conjunction with non-uniform distribution of nanotubes from the surface to the bulk in the polymer matrix enables a significant enhancement of the temperature coefficient of resistance, which leads to high mid-IR bolometric responsivity. 

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Figure 2.17 CNT-polymer composite IR sensors. UV-Vis-near-IR spectra of (a) 5 wt% SWNTHiPco-PC and (b) 5 wt% SWNTcoMocat-PC composite thin films. Mil, Sii, and S22 represent optical transitions in metallic and semiconducting SWNTs, respectively.(c) Schematic experimental setup. Near-IR light covers all of the sample area, (d) Relative conductivity a (Jdark) responses of SWNT-PC nanocomposites to the on/off IR illumination (power intensity 7 mW mm ).

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