Premium
Reactive oxygen species in stoichiometric ceria: Bulk and low‐index surfaces
Author(s) -
Kullgren Jolla,
Hermansson Kersti,
Broqvist Peter
Publication year - 2014
Publication title -
physica status solidi (rrl) – rapid research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.786
H-Index - 68
eISSN - 1862-6270
pISSN - 1862-6254
DOI - 10.1002/pssr.201409099
Subject(s) - stoichiometry , chemistry , oxygen , endothermic process , superoxide , reactive oxygen species , peroxide , exothermic reaction , molecule , adsorption , inorganic chemistry , photochemistry , organic chemistry , biochemistry , enzyme
We have calculated the stabilities of some reactive oxygen species (ROS) in stoichiometric bulk ceria and at the low‐index (111) and (110)‐surfaces, both in vacuum and in the presence of additional O 2 molecules. We find that the formation of intrinsic ROS, here oxygen superoxides (O 2 – ) and peroxides (O 2 2– ), is always endothermic at vacuum conditions and that the superoxide formation always leads to a higher formation energy than the peroxide formation. In the presence of additional O 2 molecules, intrinsic peroxide formation becomes exothermic at the (110)‐surface in conjunction with the formation of extrinsic superoxide ions from adsorbed O 2 molecules. This coexistence of intrinsic and extrinsic ROS species is anticipated to be stable at low temperatures, and can be important for understanding the ROS chemistry for nanoceria used in low‐temperature applications.Oxygen‐assisted reduction of the ceria(110) surface. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)