Institute of Inorganic Chemistry, Department of Chemistry, University of Cologne, Greinstraße 6, Cologne 50939, Germany.
University of Applied Sciences Upper Austria, Stelzhamerstraße 23, Wels 4600, Austria.
Biomacromolecules. 2021 Apr 12;22(4):1739-1751. doi: 10.1021/acs.biomac.1c00175. Epub 2021 Mar 9.
Due to the current energy crises, the search for thermal energy management systems based on thermal insulating porous materials has drawn a significant deal of attention. Herein, we demonstrated the thermal insulation and management capabilities of cuttlefish bone mimetic aerogels with hierarchically organized porous structures directly fabricated from surface-modified and self-assembled silk fibroin (SF) biopolymer extracted from silkworm cocoon biomass; hereafter, the materials developed referred to as X-. Exploiting from creating an interpenetrating network of the secondary ceramic components of various one-, two-, and three-dimensional sepiolite (MgHSiO·HO), MXene (TiCT), and silica nanostructures inside the self-assembled SF biopolymer and subsequent uni-directional freeze-casting and drying the resulted hydrogels, composites with aerogel features were obtained. The obtained aerogels possess low bulk density (ρ = 0.059-0.090 g cm), low thermal conductivities (λ = 0.035-0.042 W m K), and high thermal stability (up to ∼260 °C) with multi-modal lamella-bridge porous microstructures found in the cuttlefish bone structure. In addition, the intriguing anisotropy in the X- composite porous structure enables thermal dissipation along with the aligned pore directions, thus decreasing the local overheating on the heated side. As a result, an improvement in thermal insulation in the perpendicular direction with respect to the pore lamellae was obtained. Therefore, the exquisite thermal energy management, biodegradability, low bulk density, fire resistivity, together with possible manufacture scalability of X- composite, make this material attractive for future practical applications.
由于当前的能源危机，基于隔热多孔材料的热能管理系统的研究引起了广泛关注。在此，我们展示了具有分级多孔结构的墨鱼骨仿生气凝胶的隔热和管理能力，这些气凝胶是直接由经过表面修饰和自组装的丝素（SF）生物聚合物制备的，丝素是从蚕茧生物质中提取的。此后，开发的材料称为 X-。通过在自组装 SF 生物聚合物内部创建各种一维、二维和三维海泡石（MgHSiO·HO）、MXene（TiCT）和二氧化硅纳米结构的次级陶瓷成分的互穿网络，并随后对所得水凝胶进行单向冷冻铸造和干燥，获得了具有气凝胶特征的复合材料。所得到的气凝胶具有低体密度（ρ=0.059-0.090 g cm）、低热导率（λ=0.035-0.042 W m K）和高热稳定性（高达约 260°C），并且具有墨鱼骨结构中发现的多模态薄片-桥多孔微观结构。此外，X-复合材料多孔结构中的各向异性使热量沿着排列的孔方向耗散，从而减少了加热侧的局部过热。结果，在垂直于孔薄片的方向上获得了隔热性能的提高。因此，X-复合材料的出色的热能管理、生物降解性、低体密度、防火性以及可能的制造可扩展性使其在未来的实际应用中具有吸引力。
