3D printing strong and conductive geo-polymer nanocomposite structures modified by graphene oxide

Preparation of inks with proper rheology performance is the key for extrusion based 3D printing. In this work, extrusion based 3D printing graphene oxide (GO)/geopolymer (GOGP) nanocomposite was reported for the first time. The addition of GO in geopolymeric aqueous mixture (alumiosilicate and alkaline-source particles) dramatically changes its rheology properties, and enable the 3D printing that cannot be realized solely by geopolymer. The 3D printing GOGP structures exhibited high mechanical properties with compressive strength higher than 30 MPa, and electrical conductivity of 10² S/m was achieved after annealing, which is among the highest conductive ceramic nanocomposites. We expect that the rheology modification mechanism proposed in this study will facilitate the 3D printing of diverse materials, as well as the understanding of the interaction between GO and hydrophilic particles.