2D Nano‐Quartz Aerogels Cloned via Chemical Vapor Deposition Enable High‐Power Laser Scattering

Artificial synthesis of silica aerogel, either with crystalline quartz building blocks rather than present amorphous ones, or with greater than 0D building blocks rather than present nano-spherical ones, has become a century-old problem in light of its invention in 1931. Herein, 2D nano-quartz aerogels (QAs) with various configurations (e.g., ultrafine or hollow fiber, thin film, lightweight monolith, etc.) are all successfully cloned by chemical vapor deposition of silica source onto graphene aerogel skeletons to form ultrathin ceramic layers with carbon-leaving-induced crystallization during subsequent carbon etching. These QAs not only possess large amounts of graphene-like nanosheets with typical α-quartz phase, but exhibit ultralow density (as low as 1.5 mg cm^-3), large specific surface area (up to 836 m² g^-1), superior thermal-insulation (∼20 mW m^-1·K^-1 in air), configuration-dependent flexibility, more than 600 °C higher thermal stability than traditional amorphous silica aerogel, and promising high-power (>10² W) light-scattering ability, indicating these QAs might be used as the distinct diffusers for high-power laser-driven lighting and high power laser shielding. This research might open numerous possibilities in developing quartz-like crystalline aerogels with 2D nano-building blocks.