Toward improved optical transparency of silica nanofibrous aerogels

Silica aerogel, renowned for its low thermal conductivity and high optical transparency, is widely used as a transparent insulating material. However, its inherent fragility significantly hinders its practical performance. In this study, a type of nanofibrous silica aerogel is investigated to strengthen the mechanical properties and achieve improved optical transparency. The fibrous microstructure of aerogel is numerically reproduced by the Voronoi Tessellation algorithm. Its radiative properties are analyzed through a combination of the discrete dipoles approximation (DDA) and the Monte Carlo (MC) method, examining the influence of frame structure, fiber radius, porosity, and thickness. Findings indicate that aerogels with fiber radius under 1 nm, over 95% porosity, and thickness below 1 cm fulfill the criteria for light transmission and haze necessary for energy-efficient windows. Energy simulations of fibrous aerogel windows across various Chinese climates suggested up to 45% of energy savings compared to traditional single-pane windows. Furthermore, the study assessed the economic and environmental advantages of aerogel windows throughout their life cycle, offering valuable insights for sustainable building design.