Study of elastic silicon-based aerogels for inertial confinement fusion targets

Background In inertial confinement fusion research, the storage and rapid filling of deuterium-tritium fuel place stringent demands on target materials, which must simultaneously exhibit low density, high specific surface area, and strong hydrophobicity.

Purpose To address these requirements, this work develops an superhydrophobicity elastic aerogel through a controllable sol–gel system.

Methods Methyltriethoxysilane (MTES) was used as the precursor and monohydroxyl-terminated polydimethylsiloxane (PDMS) as an organic reinforcing component, while a mixed solvent of isopropanol (IPA) and N,N-dimethylformamide (DMF) was employed, followed by ambient-pressure drying.

Results By systematically monitoring the homogeneity of the precursor solution before condensation as functions of PDMS content and the solvent volume ratio V_IPA/V_DMF, a dissolution phase diagram within the IPA-DMF-PDMS ternary parameter space was established, revealing the governing factors for solution stability. For compositions located in the homogeneous region, the influence of solvent ratio on microstructure and macroscopic properties was further investigated. The results show that increasing V_IPA/V_DMF leads to a structural evolution of the aerogel framework from isotropic spherical particles to anisotropic, dumbbell-like interconnected networks, accompanied by the formation of hierarchical micron–macron pores. The resulting aerogels exhibit densities below 0.2 g/cm³, water contact angles exceeding 150°, and specific surface areas above 500 m²/g, with a theoretical DT adsorption capacity on the order of 10⁻² mol/g, comparable to materials prepared via supercritical drying. Additionally, the materials display excellent elasticity, achieving complete recovery after 45% compressive strain and a maximum compressive strength of 88 kPa.

Conclusions These results demonstrate that the developed aerogel possesses combined advantages of high surface area, superhydrophobicity, and mechanical resilience, providing a promising material strategy for low-density porous components in ICF target fabrication.