Department of Chemistry, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States.
J Am Chem Soc. 2017 Apr 5;139(13):4667-4670. doi: 10.1021/jacs.7b01593. Epub 2017 Mar 22.
Practical applications of metal-organic framework (MOF) materials require an in-depth understanding of their mechanical properties. We have investigated the mechanical properties and energy absorption behavior of single crystals of four isostructural UiO-type MOFs under uniaxial compression. In situ nanocompression experiments were used to measure the mechanical behavior of individual MOF nanocrystals under compression within a transmission electron microscope. The plasticity and endothermicity during deformation of MOFs shows a surprising potential for absorption and dissipation of mechanical shock. At compressive stress below 2 GPa, relatively small amounts of energy (<0.3 kJ/g) are absorbed by the compression of these MOFs. As the stress was increased, however, the energy absorption was significantly enhanced. Above 2 GPa, the energy absorption typically reaches 3-4 kJ/g; for comparison, the energy release in the explosion of TNT is ∼4 kJ/g. Gram for gram, MOFs can absorb as much energy as a high explosive can release.
实际应用的金属-有机骨架（MOF）材料需要深入了解其力学性能。我们研究了四种同构 UiO 型 MOF 单晶在单轴压缩下的力学性能和能量吸收行为。原位纳米压缩实验用于在透射电子显微镜内测量单个 MOF 纳米晶体在压缩下的力学行为。MOF 在变形过程中的塑性和吸热性显示出吸收和耗散机械冲击的巨大潜力。在 2 GPa 以下的压缩应力下，这些 MOF 的压缩吸收的能量相对较小（<0.3 kJ/g）。然而，随着应力的增加，能量吸收显著增强。超过 2 GPa 时，能量吸收通常达到 3-4 kJ/g；相比之下，TNT 爆炸释放的能量约为 4 kJ/g。一克 MOF 可以吸收的能量与一克高能炸药释放的能量相当。
