A printing capability for gels and aerogels, with great replication fidelity at 10-1000 µm length scale, creates the possibility for spatially varying aerogel compositions and functions and enables a breakthrough in a technological adoption of aerogels for multi-functional assembly and miniaturization applications. At Empa, we developed a direct ink writing protocol to print aerogel objects based on custom-tailored precursors systems [1]. Functional (nano)particles or various polymers are easily incorporated. The method enables the production of miniaturized objects with outstanding shape fidelity.

The printed aerogel can be pure silica, pure polymers, or hybrids with tailored compositions and functions, with an excellence performance due to the intrinsic aerogel properties (e.g. equivalent S_BET and λ of 751 m²/g, 15.9 mW∙m^-1∙K^-1 for printed silica aerogels). We demonstrated proof of concepts for additive manufacturing of a variety of material systems, including silica, alumina, polyimide, nanocellulose aerogel materials.