Photothermal Cantilever Deflection Spectroscopy of Physisorbed Naphtha

  • Author / Creator
    Bagheri, Mehrdad
  • We have used photothermal cantilever deflection spectroscopy (PCDS) for selective and sensitive detection of hydrocarbons with a particular emphasis on monitoring naphtha physisorbed on cantilevers. In PCDS, molecules physisorbed on a bi-material microcantilever are illuminated with a mid-infrared light from a monochromator. Here, we report on detecting and molecularly discriminating nanogram quantities of hydrocarbons on the cantilever using PCDS technique. The obtained PCDS and traditional IR spectroscopies results are in excellent concurrence. We also developed a technique to determine the effective convection heat transfer (h) for the microcantilevers used in our PCDS experiments by measuring the bending of the cantilever in response to the variations of the cantilever base temperature Tb. The designed experiment is straightforward and accurate. This yields a value of 1350-1650 W/k.m2. We point out that the thermal sensitivity and the optimum thickness ratio of bi-material cantilevers used in PCDS setups depends on h.

  • Subjects / Keywords
  • Graduation date
    Fall 2012
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.