Directing near-infrared photon transport with core@shell particles

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A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
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AIP ADVANCES, Volume 10, issue 9
Directing the propagation of near-infrared radiation is a major concern in improving the efficiency of solar cells and thermal insulators. A facile approach to scatter light in the near-infrared region without excessive heating is to embed compact layers with semiconductor particles. The directional scattering by semiconductor@oxide (core@shell) spherical particles (containing Si, InP, TiO2, SiO2, or ZrO2) with a total radius varying from 0.1 μm to 4.0 μm and in an insulating medium at a low volume fraction is investigated using Lorenz-Mie theory and multiscale modeling. The optical response of each layer is calculated under irradiation by the Sun or a blackbody emitter at 1180 K. Reflectance efficiency factors of up to 83.7% and 63.9% are achieved for near-infrared solar and blackbody radiation in 200 μm thick compact layers with only 1% volume fraction of bare Si particles with a radius of 0.23 μm and 0.50 μm, respectively. The maximum solar and blackbody efficiency factors of layers containing InP particles were slightly less (80.2% and 60.7% for bare particles with a radius of 0.25 μm and 0.60 μm, respectively). The addition of an oxide coating modifies the surrounding dielectric environment, which improves the solar reflectance efficiency factor to over 90%, provided it matches the scattering mode energies with the incident spectral density. The layers are spectrally sensitive and can be applied as a back or front reflector for solar devices, high temperature thermal insulators, and optical filters in gradient heat flux sensors for fire safety applications.
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Conley , K M , Thakore , V , Seyedheydari , F , Karttunen , M & Ala-Nissila , T 2020 , ' Directing near-infrared photon transport with core@shell particles ' , AIP Advances , vol. 10 , no. 9 , 095128 .