Formation of environmentally persistent free radicals (EPFRs) on ZnO at room temperature: Implications for the fundamental model of EPFR generation.

Authors

Matthew C. Patterson, Louisiana State University, Baton Rouge
Mark F. DiTusa, Louisiana State University, Baton Rouge
Cheri A. McFerrin, Department of Natural Sciences and Mathematics, Dominican University of California
R. L. Kurtz, Louisiana State University, Baton Rouge
Randall W. Hall, Department of Natural Sciences and Mathematics, Dominican University of CaliforniaFollow
E. D. Poliakoff, Louisiana State University, Baton Rouge
P. T. Sprunger, Louisiana State University, Baton Rouge

Department

Natural Sciences and Mathematics

Document Type

Article

Source

Chemical Physics Letters

Publication Date

2-16-2017

ISSN

0009-2614

Volume

670

First Page

5

Last Page

10

Abstract

Environmentally persistent free radicals (EPFRs) have significant environmental and public health impacts. In this study, we demonstrate that EPFRs formed on ZnO nanoparticles provide two significant surprises. First, EPR spectroscopy shows that phenoxy radicals form readily on ZnO nanoparticles at room temperature, yielding EPR signals similar to those previously measured after 250°C exposures. Vibrational spectroscopy supports the conclusion that phenoxy-derived species chemisorb to ZnO nanoparticles under both exposure temperatures. Second, DFT calculations indicate that electrons are transferred from ZnO to the adsorbed organic (oxidizing the Zn), the opposite direction proposed by previous descriptions of EPFR formation on metal oxides.

PubMed ID

28824195

Creative Commons License

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