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Abstract Tailoring thermal transport by structural parameters could result in mechanically fragile and brittle networks. An indispensable goal is to design hierarchical architecture materials that combine thermal and mechanical properties in a continuous and cohesive network. A promising strategy to create such a hierarchical network targets additive manufacturing of hybrid porous voxels at nanoscale. Here we describe the convergence of agile additive manufacturing of porous hybrid voxels to tailor hierarchically and mechanically tunable objects. In one strategy, the uniformly distributed porous silica voxels, which form the basis for the control of thermal transport, are non-covalently interfaced with polymeric networks, yielding hierarchic super-elastic architectures with thermal insulation properties. Another additive strategy for achieving mechanical strength involves the versatile orthogonal surface hybridization of porous silica voxels retains its low thermal conductivity of 19.1 mW m−1 K−1, flexible compressive recovery strain (85%), and tailored mechanical strength from 71.6 kPa to 1.5 MPa. The printed lightweight high-fidelity objects promise thermal aging mitigation for lithium-ion batteries, providing a thermal management pathway using 3D printed silica objects.
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Flexible percolation fibrous thermal insulating composite membranes for thermal management
Flexible thermal insulating membranes are ubiquitous in thermal management. Nevertheless, difficulties arise for composite membranes to combine a resilient, robust structural framework with uniform percolation networks purposefully conceived for thermal insulation. Herein, by controlling the microstructure homogeneity, we report flexible, hydrophobic thermal insulating membranes consisting of ceramic fiber and porous silica materials. The resulting nanofibrous membrane composites exhibit a low thermal insulation of 11.4 mW m−1 K−1, a low density of 0.245 g cm−3, mechanical flexibility with a bending rigidity of 1.25 cN mm−1, and hydrophobicity with a water contact angle of 144°. These nanofibrous-reinforced, silica-aerogel-based nanocomposite membranes are potential candidates for advanced thermal management applications.
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- Award ID(s):
- 2143662
- PAR ID:
- 10388810
- Publisher / Repository:
- Royal Society of Chemistry Publishing
- Date Published:
- Journal Name:
- Materials advances
- ISSN:
- 2633-5409
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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