The Effect Of Crystal Structure on The Morphology Of Marine Aerosol And Design Of TPD Spectrometer for UHV Chamber

Open Access
Author:
Ucci, Alexander
Graduate Program:
Chemistry
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
January 24, 2014
Committee Members:
  • Miriam Arak Freedman, Thesis Advisor
  • Thomas E Mallouk, Thesis Advisor
  • Nicholas Winograd, Thesis Advisor
  • Jerry Y Harrington, Thesis Advisor
Keywords:
  • aerosol
  • AFM
  • TPDS
  • TEM
  • morphology
  • sea salt
  • ice nucleation
  • mass spectrometry
  • UHV
  • atmospheric chemistry
  • Feulner cap
Abstract:
Aerosol particles are ubiquitous in the atmosphere and have consequences for the climate, environment, and human health. To gain a better understanding of aerosol particles, the morphology and surface properties are investigated in two separate projects. Transmission electron microscopy (TEM) coupled with energy dispersive X-ray spectroscopy (EDS) are used to determine the structure and composition of sea salt particles, which play an important role in the marine boundary layer. In a separate project, an Ultrahigh Vacuum (UHV) instrument with temperature programmed desorption (TPD) capabilities is used to gain a better understanding of adsorbate-adsorbate and adsorbate-substrate interactions on atmospherically relevant substrates. To improve sensitivity to the desorption of water, a Feulner cap was designed and placed over the ionization volume of the mass spectrometer. By performing laboratory studies on the morphology and surfaces of aerosol particles, better parameters for climate models can be developed. Minimizing discrepancies between satellite retrievals and climate models will allow future changes to the climate to be predicted more accurately.