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Title: Additive manufacturing of complex micro-architected graphene aerogels
Graphene is one of the stiffest materials ever measured, and yet foams of this material experience such massive degradation in mechanical properties at low densities that they are worse than polymer foams. (Z. Qin, G. S. Jung, M. J. Kang and M. J. Buehler, Sci. Adv., 2017, 3, e1601536). 3D printed mechanical metamaterials have shown the unprecedented ability to alleviate such degradation, but all current 3D printing techniques capable of printing graphene foam are unable to reproduce the complex metamaterial architectures (e.g. insufficient resolution, toolpath limitations, etc.). Here we demonstrate high-resolution graphene foams incorporating hierarchical architecture which reduces mechanical degradation of graphene foams with decreasing density. Our technique achieves an order-of-magnitude finer resolution and far more intricate structures than any previous method. This technique opens new possibilities not only to enhance graphene foam mechanical properties, but to explore complex architectures and mesoscale effects for other graphene applications including energy storage and conversion, separations, and catalysis.
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Materials horizons
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National Science Foundation
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