Activation of plasmons and polarons in solar control cesium tungsten bronze and reduced tungsten oxide nanoparticles


Dispersions of reduced tungsten oxide and tungsten bronze nanoparticles are known to show a remarkable absorption of near-infrared (NIR) light applicable to solar control filters for automotive and architectural windows. Origin of the NIR absorption has been investigated by analyzing dielectric constants of CsxWO3 (x = 0.15, 0.25, and 0.33) and WO2.72, and using Mie scattering theory. The optical analysis and Mie scattering theory analysis indicate that a localized surface plasmon resonance and polarons of localized electrons contribute alongside to the observed NIR absorption at different wavelengths.

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The authors appreciate the cooperation of Takeshi Chonan in preparing the HIP specimens. They also thank Profs. Masami Terauchi and Yohei Sato of Tohoku University for helpful discussions.

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Correspondence to Kenji Adachi.

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Adachi, K., Asahi, T. Activation of plasmons and polarons in solar control cesium tungsten bronze and reduced tungsten oxide nanoparticles. Journal of Materials Research 27, 965–970 (2012).

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  • Nanoscale
  • Optical properties