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Processing solvated graphene by ink printing technique holds exciting prospective in fabricating macroscopic carbonaceous materials with designed structures and outstanding properties. Direct ink writing has been utilized for highly porous graphene aerogels for multifunctional uses. However, densified graphene solid materials have kept unreached by 3D printing for the conflict between high concentration and good homogeneousness of printing ink. Here, we have fabricated high density compact graphene microlattices (CGM) with ordered structure via liquid crystalline (LC) direct ink writing. Concentrated but homogeneous graphene oxide/glycerol inks were prepared, reaching a solid containing up to ∼6 wt% and possessing LC nature. The flow unified LC order of inks renders highly ordered micro-structure of CGM, outstanding compressive strength (62.7 MPa at 90% strain) and high electrical conductivity of 2073 S m−1. Our CGM also exhibit an impressive elasticity up to 15–18% strain. Our facile methodology has introduced a graphene solid architecture material with high mechanical properties and multi functionalities, which should become a useful engineered carbon scaffolds with designed multiscale structures, mechanical and functional properties. Image 1 [ABSTRACT FROM AUTHOR]

Abstract: Graphene aerogel microlattices (GAMs) hold great prospects for many multifunctional applications due to their low density, high porosity, designed lattice structures, good elasticity, and tunable electrical conductivity. Previous 3D printing approaches to fabricate GAMs require either high content of additives or complex processes, limiting their wide applications. Here, a facile ion‐induced gelation method is demonstrated to directly print GAMs from graphene oxide (GO) based ink. With trace addition of Ca2+ ions as gelators, aqueous GO sol converts to printable gel ink. Self‐standing 3D structures with programmable microlattices are directly printed just in air at room temperature. The rich hierarchical pores and high electrical conductivity of GAMs bring admirable capacitive performance for supercapacitors. The gravimetric capacitance (Cs) of GAMs is 213 F g−1 at 0.5 A g−1 and 183 F g−1 at 100 A g−1, and retains over 90% after 50 000 cycles. The facile, direct 3D printing of neat graphene oxide can promote wide applications of GAMs from energy storage to tissue engineering scaffolds. [ABSTRACT FROM AUTHOR]