Nanoparticles of TiO2 and VO2 in dielectric media: Conditions for low optical scattering, and comparison between effective medium and four-flux theories
2014 (English)In: Solar Energy Materials and Solar Cells, ISSN 0927-0248, Vol. 130, no SI, 132-137 p.Article in journal (Refereed) Published
Spectral transmittance and reflectance in the 300 to 2500 nm solar-optical wavelength range were calculated for nanoparticles of titanium dioxide and vanadium dioxide with radii between 5 and 100 nm embedded in transparent dielectric media. Both of the materials are of large importance in green nanotechnologies: thus TiO2 is a photocatalyst that can be applied as a porous film or a nanoparticle composite on indoor or outdoor surfaces for environmental remediation, and VO2 is a thermochromic material with applications to energy-efficient fenestration. The optical properties, including scattering, of the nanoparticle composites were computed from the Maxwell–Garnett effective-medium theory as well as from a four-flux radiative transfer model. Predictions from these theories approach one another in the limit of small particles and in the absence of optical interference. Effects of light scattering can be modeled only by the four-flux theory, though. We found that nanoparticle radii should be less than ~20 nm in order to avoid pronounced light scattering.
Place, publisher, year, edition, pages
Saunders Elsevier, 2014. Vol. 130, no SI, 132-137 p.
Condensed Matter Physics Engineering and Technology
Research subject Physics with spec. in Atomic, Molecular and Condensed Matter Physics; Engineering Science with specialization in Solid State Physics
IdentifiersURN: urn:nbn:se:uu:diva-236205DOI: 10.1016/j.solmat.2014.06.036ISI: 000343612600017OAI: oai:DiVA.org:uu-236205DiVA: diva2:763465
FunderSwedish Research Council, 80560201