Diffusion and Reactions of Photoinduced Interstitial Oxygen Atoms in Amorphous SiO2 Impregnated with O-18-Labeled Interstitial Oxygen Molecules

作者：Kajihara Koichi^*; Skuja Linards; Hosono Hideo

来源：Journal of Physical Chemistry C, 2014, 118(8): 4282-4286.

DOI：10.1021/jp412606a

Both diffusion and reactions of interstitial oxygen atoms (O-0) in amorphous SiO2 (a-SiO2) were examined using oxygen-excess a-SiO2 containing O-18-labeled interstitial oxygen molecules (O-2) and exposed to F-2 laser light (hv = 7.9 eV). Both the F2 laser photolysis of interstitial O-2 at 77 K and subsequent heat treatment at greater than or similar to 200 degrees C give rise to oxygen exchange between residual interstitial O-2 and oxygen atoms in the a-SiO2 network, and these temperatures are far lower than the temperature at which conventional thermal network-interstitial oxygen exchange in unirradiated a-SiO2 occurs (greater than or similar to 700 degrees C). However, at the initial stage of the low-temperature F-2 laser photolysis, an efficient formation of interstitial ozone molecules (quantum yield greater than or similar to 0.06) via nearly exchange-free diffusion of photogenerated interstitial O-0 is observed, and this reaction predominates over the network-interstitial oxygen exchange.

• 出版日期2014-2-27