6533b838fe1ef96bd12a4e8b

RESEARCH PRODUCT

Diffusion and Reactions of Hydrogen inF2-Laser-IrradiatedSiO2Glass

Koichi KajiharaHideo HosonoLinards SkujaMasahiro Hirano

subject

In situMaterials scienceHydrogenDiffusionHydrogen moleculeGeneral Physics and Astronomychemistry.chemical_elementPhotochemistryLaserlaw.inventionLaser photolysischemistrylawIrradiationAtomic physics

description

The diffusion and reactions of hydrogenous species generated by single-pulsed F2 laser photolysis of SiO-H bond in SiO2 glass were studied in situ between 10 and 330 K. Experimental evidence indicates that atomic hydrogen (H0) becomes mobile even at temperatures as low as approximately 30 K. A sizable number of H0 dimerize by a diffusion-limited reaction into molecular hydrogen (H2) that may migrate above approximately 200 K. Activation energies for the diffusion, inherently scattered due to the structural disorder in glass, are separated into three bands centered at approximately 0.1 eV for free H0, approximately 0.2 eV presumably for shallow-trapped H0, and approximately 0.4 eV for H2.

https://doi.org/10.1103/physrevlett.89.135507