Investigation and Characterization of Composite Silica Aerogel Nanostructures Obtained Via Magnetron Sputtering

This study explores the deposition of Copper (Cu) onto hydrophilic Silica Aerogel (SA) monoliths using magnetron sputtering, with Cu thicknesses of 20 nm, 50 nm, and 100 nm. Leveraging the mesoporous nanostructure of SA, a Cu-sputtered SA nanocomposite was fabricated, creating a non-homogeneous nanocomposite material. Trace amounts of Cu penetrate up to 10 µm into the SA structure, as revealed by SEM-EDS analysis. The resulting nanocomposite, characterized by spectrophotometric examination, exhibited UV scattering, high transmittance, and absorption in the visible range. FTIR spectra revealed reduced transmission in the near-infrared (NIR) and mid-infrared (MIR) regions with increasing Cu thickness. Infrared imaging showed a photothermal effect. The temperatures of samples comprising 100 nm of Cu sputtered onto Silica aerogels reached 94.8°C under solar-simulated irradiation at an intensity of 100 mW/cm^2. These findings provide fundamental context to an under explored area, laying the groundwork for alternative thin-film deposition techniques like magnetron sputtering deposition for the fabrication of metallic, nanocomposite Silica aerogel supports.