Integrating Aerogel into van der Waals Crystals for a High-Strength Thermal Insulator

Abstract

Achieving low thermal conductivity and high mechanical strength presents a material design challenge due to intrinsic trade-offs, such as the aerogel’s porosity, impeding applications in construction, industry, and aerospace. This study presents a composite that incorporates a silica aerogel within a thermally expanded 2D layered vermiculite matrix. This design overcomes limitations imposed by van der Waals bonding lengths, typically less than 10 Å, which hinder aerogel integration with van der Waals crystals. Our method employs a thermal spark reaction to expand the vermiculite interlayer space, allowing aerogel incorporation. This maintains aerogel’s intrinsic low thermal conductivity of 29.6 mW m^–1 K^–1, while enhancing its Young’s modulus to 66.0 MPa─a more than 10³-fold increase over pure aerogel. The innovative embedding of aerogels within van der Waals crystals marks a significant advancement in high-strength insulation technology, paving the way for development in demanding environments that require thermal management without compromising structural integrity.