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Photoacoustic characteristics of carbon-based infrared absorbers
Jussi Rossi1, Juho Uotila2, Sucheta Sharma3
1Photonics Laboratory, Physics Unit, Tampere University, Tampere, Finland.
Abstract:
We present an experimental comparison of photoacoustic responsivities of common highly absorbing carbon-based materials. The comparison was carried out with parameters relevant for photoacoustic power detectors and Fourier-transform infrared (FTIR) spectroscopy: we covered a broad wavelength range from the visible red to far infrared (633 nm to 25 μm) and the regime of low acoustic frequencies (< 1 kHz). The investigated materials include a candle soot-based coating, a black paint coating and two different carbon nanotube coatings. Of these, the low-cost soot absorber produced clearly the highest photoacoustic response over the entire measurement range.
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