10th International Aerosol Conference September 2 - September 7, 2018 America's Center Convention Complex St. Louis, Missouri, USA
Abstract View
Aerosol-assistant Synthesis of Sodium Tungsten Bronze Oxide for UV and IR Shielding
HAO TU, Wei-Ning Wang, Da-Ren Chen, Virginia Commonwealth University
Abstract Number: 353 Working Group: Materials Synthesis
Abstract The spectrum of solar radiation typically include 10% ultraviolet light (UV), 40% visible light and 50% infrared (IR) light. It is known that UV light is harmful because its high-energy photons can break down the organic bond, potentially resulting in the degradation of matter degradation, eye damage and skin aging. The IR light is the major source of heat radiation. In the summer time, the IR light often raises the temperature in the indoor space when penetrating through windows. The cooling of the indoor space to keep indoor residents comfort consumes much energy. In winters, the indoor heat is partially lost through the IR radiation. Windows with the feature of shielding UV and IR lights while keeping transparent for visible lights have the potential to prevent the residents in the indoor space from the UV radiation while saving energy for cooling the indoor space in summers and heating in winters.
With the properties to absorb the light at in the wavelength less than 370 nm and greater than 800 nm and to be transparent for visible light, sodium tungsten bronze oxide is a perfect functional material for target applications in this study. As a member of tungsten oxides, tungsten bronze oxide is highly resistant to the photochemical corrosion and material degradation and is able to sustain very high temperature, making it suitable for long-term application in hazardous environment. In the literatures, tungsten bronze oxides are synthesized by either hydrothermal, solid reaction or sputtering methods. All of these methods are batched and often require long production time. To the author's knowledge, the above material has not been synthesized by an aerosol route, which is a continuous process to produce materials with high purity and can be easily scaled up in the production.
For the first time, nanoparticles of sodium tungsten bronze oxide were synthesized by an aerosol route in this work. The produced powder of sodium tungsten bronze oxide via the developed aerosol route shows comparable characteristics for the UV and IR light shielding, and the visible light transmittance as the reported one given in literatures. Additionally, a parametric study was also preformed to investigate the effects of the sodium-to-tungsten ratio and operational variables (i.e., the flow rate and heating temperature) on the crystal structure, light absorbance and elemental composition of as-produced powder materials. The details of the developed aerosol route and the result of parametric study will be given in this presentation.