Preparation and characterization of hollow silica nanocomposite functionalized with UV absorbable molybdenum cluster

Abstract

The nanoparticle-based material technology has recently opened a new heat shielding material generation for window applications such as aerogel, vacuum insulation panel or nanospace materials. Aiming to prepare a nanospace-based heat insulation material functionalized with an ultraviolet (UV) absorbent, the Mo6 cluster-deposited hollow silica nanoparticles (HSNs) were prepared by the vacuum impregnation process (VIP). The pore channels of the hollow silica wall filled with the Cs2[Mo6Ii8(OCOC2F5)a6] octahedral cluster (CMIF) were confirmed by an HR-TEM coupled EDX device, ICP-OES and BET analysis. The retention of the octahedral structure or the typical optical property of the Mo6 cluster in the pores of the HSNs was demonstrated by ultraviolet (UV) light absorption and photoluminescence spectroscopes even though the powders were heated to 200 °C. The multi-functional CMIF@HSNs nanocomposite could adsorb the UV rays under 400 nm and scatter the NIR light through the pores of the silica wall in order to reduce the heat passing a window. For this purpose, the film preparation based on the CMIF@HSNs nanocomposite was performed by dip coating in the commercially available top coat suspension (TCS) on soda lime glass. Excellent mechanical and optical properties of the CMIF@HSNs-based thin film were visibly obtained with a relative transmittance. This study suggests a potential insulation material prepared by a high efficiency and simple method for reducing the air temperature in buildings.