Institute for Materials Science , University of Stuttgart , Heisenbergstrasse 3 , 70569 Stuttgart , Germany.
Department of Chemistry , University of California , Berkeley , California 94720 , United States.
Nano Lett. 2018 Apr 11;18(4):2519-2524. doi: 10.1021/acs.nanolett.8b00194. Epub 2018 Mar 23.
The demand to outperform current technologies pushes scientists to develop novel strategies, which enable the fabrication of materials with exceptional properties. Along this line, lightweight structural materials are of great interest due to their versatile applicability as sensors, catalysts, battery electrodes, and acoustic or mechanical dampers. Here, we report a strategy to design ultralight (ρ = 3 mg/cm) and hierarchically structured ceramic scaffolds of macroscopic size. Such scaffolds exhibit mechanical reversibility comparable to that of microscopic metamaterials, leading to a macroscopically remarkable dynamic mechanical performance. Upon mechanical loading, these scaffolds show a deformation mechanism similar to polyurethane foams, and this resilience yields ultrahigh damping capacities, tan δ, of up to 0.47.
为了超越现有技术，科学家们不断寻求新的策略，以制造具有特殊性能的材料。在此背景下，由于其在传感器、催化剂、电池电极以及声或机械减振器等方面的广泛适用性，轻质结构材料受到了极大的关注。在此，我们提出了一种设计超轻量（ρ=3mg/cm）和分级结构的宏观陶瓷支架的策略。这种支架具有与微观超材料相当的机械可逆性，从而表现出显著的动态力学性能。在机械加载下，这些支架表现出类似于聚氨酯泡沫的变形机制，这种弹性可产生高达 0.47 的超高阻尼能力 tan δ。
