Enhancing NIR Shielding Properties of Au/CsWO Composite via Physical Mixing and Solvothermal Processes.

This research aims to enhance the near-infrared (NIR) shielding ability of cesium tungsten bronze (CsWO) by increasing the spectral absorption in this region through the incorporation of gold nanorods (Au). Two approaches were used to prepare the composite materials: physical mixing and solvothermal process. The effects of gold nanorods content on the crystalline size, particle size, shape, and optical properties of the composite were investigated systematically using DLS, TEM, XRD, and UV-Vis spectroscopy techniques, respectively. The physical mixing process synergizes Au and CsWO into a composite which has better NIR absorption than that of neat Au and CsWO nanorods. A composite with 10 mol% of Au shows the highest NIR absorption ability due to the surface plasmon resonance and energy coupling between Au and CsWO. With the solvothermal process, the CsWO nanorods grow up to 4-7 microns when the Au content increases to 0.8 mol% due to the incorporation of the Au atoms. The microsized CsWO rods have superior NIR shielding property compared to other conditions, including the Au+CsWO nanocomposite with 10 mol% of Au from the physical mixing process.