Quartz-crystal microbalance for in situ monitoring of laser cleaning of carbon nanotubes

Photochemical changes of single-walled carbon nanotubes, graphite and amorphous carbon have been investigated with a quartz-crystal microbalance (QCM). The method of in situ measurements reduces our uncertainty that is attributable to environmental variables, such as relative humidity and temperature. At 248 nm, near the resonance of the π-plasmon we expect the interaction of laser light and carbon nanotube material to exhibit relatively high absorptivity. We discuss the importance of the single-walled carbon nanotube surface plasmon in the reduction of carbon impurities. The QCM is a means to quantify laser damage with respect to irradiance, pulse width and exposure time.