Broadband Spectroscopic Thermoacoustic Characterization of Single-Walled Carbon Nanotubes

Figure 2

(a) Schematic cross-section of sample imaged in Figure 1(c) comprised of semiconducting SWNTs (s.c. SWNT, 300 ppm), metallic SWNTs (met. SWNT, 100 ppm), and a baseline control of deionized water (diH₂O). (b) TA image acquired with 3.1 GHz microwave radiation (8 dB dynamic range). Tubes are outlined by gray circles. Scale bar = 2 mm. (c) Average TA signal, over 4 × 4 mm² regions for semiconducting SWNTs (AU/GHz, ) and metallic SWNTs ( AU/GHz, ) relative to the normalized slope of deionized water ( AU/GHz, ) as a function of incident microwave frequency.

(a)

(b)

(c)