INVESTIGATION AND CHARACTERIZATION OF CARBON FILMS SPUTTERED ON SILICA AEROGEL MONOLITHS

Abstract

This study investigates the deposition of a 500 nm carbon (C) layer onto hydrophilic bare silica aerogels (BSA) using the magnetron sputtering method. By leveraging the mesoporous structure of silica aerogel, a carbon-coated aerogel nanocomposite was produced. Spectroscopic characterization of the resulting nano composite revealed ultraviolet scattering behavior, enhanced visible light absorption, and changes in optical transmittance. FTIR spectroscopy further demonstrated that the carbon layer reduced transmittance in the near-infrared (NIR) and mid-infrared (MIR) regions. Infrared thermal imaging confirmed a photothermal response, where samples coated with a 500 nm carbon layer reached temperatures up to 59 °C under simulated solar irradiation at an intensity of 100 mW/cm². Solara absorptance calculations further showed an increase from approximately 6.9% for BSA to 75.8% for CSSA, indicating enhanced solar energy absorption after carbon sputtering. In addition, carbon capture experiments were performed to evaluate the influence of carbon sputtering on CO₂ adsorption and desorption behavior. The findings demonstrate that carbon sputtering modified the optical and photothermal properties of silica aerogels and provided insight into their potential use in carbon capture applications.