Beyond being a key raw material for transparent heat-insulating coatings, films, or glass, cesium tungsten bronze also serves as an important production material for heat-storage fibers, significantly enhancing the comprehensive performance of functional fibers.
Heat-storage fibers are functional fibers capable of converting sunlight or infrared rays into heat energy and storing it within the fibers. They are ideal fabrics for the elderly, athletes, and outdoor workers, primarily used to produce woven and knitted textiles requiring thermal insulation, such as mountaineering clothing fabrics, warm socks, military uniforms for cold regions, and heat-storing energy carpets.
To further improve the comprehensive performance of existing heat-storage fibers, such as environmental friendliness and heat-storage capacity, researchers often add appropriate amounts of cesium tungsten nanomaterials, such as cesium tungsten bronze nanomaterials, during production.
Cesium tungsten bronze is a class of non-stoichiometric functional compounds with a unique oxygen octahedral structure, with the chemical formula CsxWO3 (where x ranges from 0 to 0.33). It boasts a purity of up to 99.99%, a primary particle size of 50 nm, a relatively wide bandgap, and characteristics such as being non-toxic, non-radioactive, possessing strong near-infrared (wavelength 800-1200 nm) absorption, and high visible light transmittance, making it suitable for producing heat-storage fibers.
The primary reason cesium tungsten bronze nanomaterials exhibit strong absorption in the infrared region is due to the presence of cation insertion structures and oxygen vacancy defects in their structure. This results in numerous free charges in Cs0.33WO3 materials, generating localized surface plasmon resonance effects on the surface of Cs0.33WO3 nanoparticles.
Owing to the excellent selective transmittance of cesium tungsten bronze nanomaterials across the spectrum—high transmittance in the visible light range (380-780 nm) and low transmittance in the near-infrared range—it is well-suited for producing transparent heat-insulating films. This ensures products maintain high visual transparency while minimizing near-infrared transmission.
