• 文献标题:   The influence of the drying method on the microstructure and the compression behavior of graphene aerogel
  • 文献类型:   Article
  • 作  者:   XIE J, NIU LL, QIAO Y, LEI YZ, LI GY, ZHANG XT, CHEN PW
  • 作者关键词:   graphene aerogel, compression behavior, drying method, cellular microstructure
  • 出版物名称:   DIAMOND RELATED MATERIALS
  • ISSN:   0925-9635 EI 1879-0062
  • 通讯作者地址:  
  • 被引频次:   8
  • DOI:   10.1016/j.diamond.2021.108772
  • 出版年:   2022

▎ 摘  要

Supercritical CO2 drying and freeze-drying are two standard drying methods for fabricating aerogels. We conducted a comprehensive experimental study for clarifying the influence of the drying method on the properties of graphene aerogel, and further discussed its deformation mechanism via characterization and simulation results. The results showed that the specific modulus of two drying methods prepared graphene aerogels is similar. The supercritical CO2 dried sample had a higher compression strength due to the plastic collapse of the mesopore walls. In the freeze-drying process without thermal baffle, the reformed honeycomb geometric microstructure can be divided into three regions according to the growth of ice crystals: vertical, transition, and gradient regions. Therefore, the freeze-dried graphene aerogels exhibited a nonlinear superelastic behavior due to the random out-of-plane buckling of the thicker pore walls. In addition, two cellular structures were developed by mimicing the microstructure of two kinds of graphene aerogels for numerical analysis. Simulation results highlighted the decisive role of geometric nonlinearity in the deformation mechanism.