AVS 63rd International Symposium & Exhibition
    Surface Science Tuesday Sessions
       Session SS+HC-TuA

Paper SS+HC-TuA11
Use of Photoluminescence to Monitor Surface Chemistry of Metal Oxide Nanoparticles

Tuesday, November 8, 2016, 5:40 pm, Room 104D

Session: Photocatalysis and Photochemistry at Surfaces
Presenter: James Whitten, University of Massachusetts Lowell
Authors: S. Kim, University of Massachusetts Lowell
D. Somaratne, University of Massachusetts Lowell
J.E. Whitten, University of Massachusetts Lowell
Correspondent: Click to Email
Many metal oxides nanoparticles are photoluminescent upon irradiation with ultraviolet light, with visible emission arising from surface states and surface defects. Because of the sensitivity of the surface to adsorption and electron transfer to and from even weakly adsorbed molecules, photoluminescece (PL) is proving to be a convenient method of monitoring chemisorption and physisorption. Experimental and theoretical results are presented related to adsorption of various gases and organic vapors on zinc oxide, zirconium oxide, and titanium dioxide nanoparticles toward the goal of correlating adsorption to PL changes. X-ray and ultraviolet photoelectron spectroscopy (XPS and UPS) and Raman spectroscopy measurements have been performed on metal oxide nanoparticles and single crystals to investigate whether chemisorption occurs at room temperature and the details of adsorbate bonding. These results are combined with density functional theory (DFT) calculations to understand how adsorption influences the PL changes. In addition to atmospheric gases, examples of adsorbates that have been examined include ammonia, methanethiol, methanol, benzene, and pyridine. This research provides a convenient method of monitoring adsorption and lays the foundation for optochemical sensing, in which metal oxides may serve as a new type of gas sensor.