Strong yet superelastic ceramic aerogel enabled by synergistic soft-hard inter-nanowire nodes
De Lu, Lei Su, Lei Zhuang, Min Niu, Kang Peng, Pengcheng Zhang, Xiaowu Wang, Zhentao Ni, Shuhai Jia, Hongjie Wang
Abstract
Elastic ceramic aerogels have drawn broad attention for use in aerospace, energy storage, and thermal protection systems, where lightweight structures with thermal stability and mechanical robustness are required. Yet their practical application is often limited by insufficient strength. Achieving both high strength and high elasticity in ceramic nanowire aerogels remains challenging because these properties are typically mutually constrained. Here we design silicon carbide nanowire aerogels reinforced by dual-phase nodes composed of pyrolytic carbon (PyC) and amorphous silica (SiO2) to resolve this conflict. Experimental measurements together with large-scale atomic/molecular massively parallel simulator (LAMMPS) and finite element simulations show that amorphous SiO2 improves load-bearing efficiency by distributing stress uniformly, while PyC relieves local stress concentrations and prevents premature SiO2 fracture, producing a clear synergistic effect. The resulting aerogels exhibit a compressive strength of 10.9 MPa at 80% strain and a resilience of about 90%. This dual-phase strategy provides an effective route to tailor the mechanical response of ceramic aerogels and expand their use in extreme environments such as high temperature, low oxygen, and vacuum conditions, where strength, elasticity, and long-term reliability are required. This study reports ceramic nanowire aerogels with dual SiO2/PyC nodes that combine high strength and elasticity, overcoming the typical strength–elasticity trade-off through a synergistic soft–hard structural design.