Impact of alkaline salts loading on structural, optical and Near-infrared shielding properties of potassium tungsten bronze materials

Authors

  • Phonlawee Pinthong Department of Nanoscience and Nanotechnology, School of Integrated Innovative Technology (SIITec), King Mongkut’s Institute of Technology Ladkrabang, Bangkok, 10520, Thailand
  • Maneerat Songpanit Department of Nanoscience and Nanotechnology, School of Integrated Innovative Technology (SIITec), King Mongkut’s Institute of Technology Ladkrabang, Bangkok, 10520, Thailand
  • Thanaphon Kansaard Department of Nanoscience and Nanotechnology, School of Integrated Innovative Technology (SIITec), King Mongkut’s Institute of Technology Ladkrabang, Bangkok, 10520, Thailand
  • Wanichaya Mekprasart Department of Nanoscience and Nanotechnology, School of Integrated Innovative Technology (SIITec), King Mongkut’s Institute of Technology Ladkrabang, Bangkok, 10520, Thailand
  • Kanokthip Boonyarattanakalin Department of Nanoscience and Nanotechnology, School of Integrated Innovative Technology (SIITec), King Mongkut’s Institute of Technology Ladkrabang, Bangkok, 10520, Thailand
  • Wisanu Pecharapa Department of Nanoscience and Nanotechnology, School of Integrated Innovative Technology (SIITec), King Mongkut’s Institute of Technology Ladkrabang, Bangkok, 10520, Thailand

DOI:

https://doi.org/10.55674/cs.v18i3.266086

Keywords:

Potassium tungsten bronze, Ball milling process, Near-infrared shielding

Abstract

Increasing heat emissions through windows directly affect energy consumption in air conditioner systems. To address this challenge, potassium tungsten bronze (KxWO3) materials are used for near-infrared shielding. The materials provide high transmission in the visible region and strong absorption at infrared wavelengths. The optical properties of these materials depend on the ratio of alkali metal to tungsten, which determines the number of donor electrons available from the alkali metal, and also the extent of reduction of tungsten from its W6+ oxidation state to its W5+ state. This interplay between oxidation states gives rise to the phenomena of localized surface plasmon resonance (LSPR) and small polaron absorption. In this work, we investigated various values of x in KxWO3 where x = 0.1, 0.3, 0.5, and 0.7, using a high-energy ball milling method to synthesize the KxWO3 powders. Characterization was conducted using X-ray diffraction (XRD) for crystalline structure, field emission scanning electron microscopy (FESEM) for powder morphology determination, X-ray photoelectron spectroscopy (XPS) for the study of the oxidation states of tungsten (W), and ultraviolet–visible–near-infrared) spectroscopy (UV–vis–NIR) for optical property investigation. The results provide correlations between the potassium ratio, the crystal structure, and the NIR shielding performance of potassium tungsten bronze materials.

GRAPHICAL ABSTRACT

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HIGHLIGHTS

  • Hexagonal tungsten bronze particles were successfully synthesized by a facile ball milling process.
  • The optimal potassium loading with K/W ratio at 0.3 stabilized the hexagonal structure, which induced near-infrared absorption efficiency.
  • 3-KWO film exhibited near-infrared shielding performance, which reduced indoor temperature by up to 4.6 °C compared with blank glass.

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Published

2026-06-02

How to Cite

Pinthong, P., Songpanit, M., Kansaard, T., Mekprasart, W., Boonyarattanakalin, K., & Pecharapa, W. (2026). Impact of alkaline salts loading on structural, optical and Near-infrared shielding properties of potassium tungsten bronze materials. Creative Science, 18(3), 266086. https://doi.org/10.55674/cs.v18i3.266086

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Vol. 18 No. 3 (2026): Creative Science (September - December) (Upcoming Issue)

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