Chemically Modified Graphene Films with Tunable Negative Poisson’s Ratios


Graphene-derived macroscopic assemblies feature hierarchical nano- and microstructures that provide numerous routes for surface and interfacial functionalization achieving unconventional material properties. We report that the microstructural hierarchy of pristine chemically modified graphene films, featuring wrinkles, delamination of close-packed laminates, their ordered and disordered stacks, renders remarkable negative Poisson’s ratios ranging from −0.25 to −0.55. The mechanism proposed is validated by the experimental characterization and theoretical analysis. Based on the understanding of microstructural origins, pre-strech is applied to endow chemically modified graphene films with controlled negative Poisson’s ratios. Modulating the wavy textures of the inter-connected network of close-packed laminates in the chemically modified graphene films also yields finely-tuned negative Poisson’s ratios. These findings offer the key insights into rational design of films constructed from two-dimensional materials with negative Poisson’s ratios and mechanomutable performance. © 2019, The Author(s).


Includes supplementary material


Films--Graphene, Poisson's ratio

National Natural Science Foundation of China (51673108 and 51433005) and National Key R&D Program of China (2016YFA0200202); National Natural Science Foundation of China through Grants 11825203 and 11472150; National Science Foundation CMMI-1636306, CMMI-1661246, and CMMI-1726435


CC BY 4.0 (Attribution), ©2019 The Authors