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RESEARCH PRODUCT
Effects of Pressure, Temperature, and Particles Size on O2 Diffusion Dynamics in Silica Nanoparticles
Roberto BoscainoSimonpietro AgnelloFranco Mario GelardiG. Iovinosubject
Materials scienceDiffusionAnalytical chemistryNanoparticleAtmospheric temperature rangeSurfaces Coatings and FilmsElectronic Optical and Magnetic Materialssymbols.namesakeGeneral EnergyDiffusion processsymbolsGrain boundary diffusion coefficientEffective diffusion coefficientPhysical and Theoretical ChemistryRaman spectroscopyBar (unit)description
The O2 diffusion process in silica nanoparticles is experimentally studied in samples of average radius of primary particles ranging from 3.5 to 20 nm and specific surface ranging from 50 to 380 (m2/g). The investigation is done in the temperature range from 98 to 177 °C at O2 pressure ranging from 0.2 to 66 bar by measuring the interstitial O2 concentration by Raman and photoluminescence techniques. The kinetics of diffusion can be described by the Fick’s equation with an effective diffusion coefficient depending on the temperature, O2 pressure, and particles size. In particular, the dependence of the diffusion coefficient on the pressure and nanoparticles size is more pronounced at lower temperatures and is connected to morphological and physical factors.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2013-04-24 | The Journal of Physical Chemistry C |