Journal of Physical Chemistry C | 2019
Interaction of SO2 with ZnO Nanoshapes: Impact of Surface Polarity
Abstract
As petroleum-related products dominate the global fuel market, acid gas resistant materials are in demand. ZnO is one of the widely used materials as SO2 sorbent and catalyst/catalyst support. To understand the surface structure sensitivity in interaction with SO2, morphology controlled ZnO wire and plate with nonpolar/polar facets have been investigated as model materials in this work. Morphology and crystal structure of nano- to micro-sized ZnO wire and plate were confirmed by SEM, XRD, and Raman characterizations. SO2 interactions with the ZnO plate (dominated by polar facet {0001}) and ZnO wire (dominated by nonpolar facet {1010}) were investigated by in situ IR coupled with temperature-programmed desorption (TPD) as well as XPS. SO2 interaction with ZnO resulted in more sulfate species on the wire than on the plate while some sulfates and sulfites still remained on both surfaces after heating to 350 °C. TPD showed higher SO2 desorption capacity on the ZnO plate surface at a lower temperature than on...