Quasi-static compression properties of graphene aerogel

• Published in: Diamond and related materials 2021-01, Vol.111, p.108225, Article 108225
• Main Authors: Niu, Lulu, Xie, Jing, Chen, Pengwan, Li, Guangyong, Zhang, Xuetong
• Format: Article
• Language: English
• Subjects: Aerogels; Axial compression; Compression tests; Compressive properties; Electron microscopy; Energy absorption; Graphene; Graphene aerogel; Mechanical properties; Microscopy; Microstructure evolution; Modulus of elasticity; Negative structural Poisson's ratio; Plastic foam; Poisson's ratio; Sol-gel processes; Surface area; Toughness
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/j.diamond.2020.108225

Graphene aerogel (GA) is a promising candidate for energy absorption purposes because of its very low density, high specific surface area and porous structure. GA samples, prepared by the Sol-Gel method, were tested under quasi-static compression, and characterized via surface area analyzer, as well as scanning electron microscopy and transmission electron microscopy. The results show that 98% (and above) porous GA samples, whose elastic modulus is 2.9 MPa, can support at least 35,000 times its weight. Scaling analysis shows that the mechanical properties of GA are superior to those of conventional polymeric open-cell foams. The GA samples exhibit a negative structural Poisson's ratio under the uniaxial compression test, which is most likely due to the bread-like microstructural evolution. Due to the mesopores of the GA sample as well as the negative structural Poisson's ratio, the GA has considerable toughness. [Display omitted] •The produced Graphene Aerogel (GA) samples have a hierarchy-porous structure with a 98% porosity.•The mechanical properties of GA are superior to those of conventional polymeric open-cell foams by a scaling law analysis.•The negative structural Poisson’s ratio of GA samples is most likely due to the bread-like microstructural evolution.•Due to the mesopores and the negative structural Poisson’s ratio, the GA has considerable toughness.