Nanoarchitectured materials composed of fullerene-like spheroids and disordered graphene layers with tunable mechanical properties

Abstract

Type-II glass-like carbon is a widely used material with a unique combination of properties including low density, high strength, extreme impermeability to gas and liquid and resistance to chemical corrosion. It can be considered as a carbon-based nanoarchitectured material, consisting of a disordered multilayer graphene matrix encasing numerous randomly distributed nanosized fullerene-like spheroids. Here we show that under both hydrostatic compression and triaxial deformation, this high-strength material is highly compressible and exhibits a superelastic ability to recover from large strains. Under hydrostatic compression, bulk, shear and Young's moduli decrease anomalously with pressure, reaching minima around 1-2 GPa, where Poisson's ratio approaches zero, and then revert to normal behaviour with positive pressure dependences. Controlling the concentration, size and shape of fullerene-like spheroids with tailored topological connectivity to graphene layers is expected to yield exceptional and tunable mechanical properties, similar to mechanical metamaterials, with potentially wide applications.

Compressed glassy carbon: An ultrastrong and elastic interpenetrating graphene network

“…3C). The compressed GCs inherit the high elasticity of raw GC that originates from the out-of-plane flexibility of sp 2 bonds ( 10 , 23 ). This mechanism is different from the reversible martensitic transformation in shape-memory alloys ( 1 ) but is similar with those in rubber and silica, that is, by the compressibility and stretchability of molecular chains ( 24 ) and rotation or bending of the SiO 4 tetrahedra during indentation, respectively ( 25 ).…”

“…Glassy carbon (GC), as a typical disordered sp 2 carbon, can be manufactured into various shapes with a great variety of unique material properties, including high strength, low density, high-temperature resistance in inert gas up to 3000°C, and extreme corrosion resistance. Type I GC, which is produced by firing polymeric precursors at temperatures below 2000°C, mainly consists of randomly distributed curved graphene layer fragments ( 10 , 11 ). Type II GC, fabricated at higher temperatures above 2500°C, contains self-assembled fullerene-like spheroids of nanometer sizes, dispersed within and interconnected by a 3D disordered multilayer graphene matrix ( 10 , 11 ).…”

“…Type I GC, which is produced by firing polymeric precursors at temperatures below 2000°C, mainly consists of randomly distributed curved graphene layer fragments ( 10 , 11 ). Type II GC, fabricated at higher temperatures above 2500°C, contains self-assembled fullerene-like spheroids of nanometer sizes, dispersed within and interconnected by a 3D disordered multilayer graphene matrix ( 10 , 11 ). During cold compression of type I GC to 44.4 GPa, synchrotron x-ray Raman spectroscopy revealed a continuous pressure-induced sp 2 -to-sp 3 bonding change ( 12 ).…”

Зависимость Механических Свойств Сорбентов От Размеров Нанопор

“…Следовательно, значения модуля Юнга 30 GPa для получаемого в эксперименте стеклоуглерода можно достичь при размере нанопор 15−20 nm, как показано в работе [14], а для других значений нанопор при той же плотности материала модуль Юнга будет изменяться.…”

“…В [14] экспериментально и теоретически по-казано, что модуль Юнга стеклоуглерода с плотно-стью 1.4 g/сm 3 составляет 30 GPa при размере нанопор 15−20 nm. При этом в [15][16][17] показано, что в процессе пиролиза можно управлять размерами пор стеклоуг-лерода.…”