(566f) Detailed Characterization and Fabrication of 3D Printed Graphene/Polymer Structures for Heterojunction-Devices with MoS2 and Other 2D Nanomaterials

It is known that the 2D nanomaterials (2DN) can be interfaced with another to realize heterostructures with controlled and/or expanded properties, which can be applied to achieve functional devices. Currently, such structures has been produced at nano- to micro-scale dimensions. Here we show that 3D printing of graphene/polymer composite can allow device fabrication with 2DN-heterostructures produced at larger and accessible scale, while leveraging their unique properties. For example, fusing graphene, a zero bandgap 2DN and MoS₂, a semiconductor 2DN, together can produce ultrafast optoelectronic switches because of the mismatched Fermi level. Graphene/polymer-MoS2-graphene/polymer junctions were produced via 3D printing and experiments were conducted to measure the carrier transport characteristics. The results from carrier-transport studied at cryogenic temperatures (25 K) to room temperature were analyzed to determine transport barriers, carrier concentrations, Coulomb blockade, inter-particle capacitance, conduction mechanism and opto-electronic response. Furthermore, the effects of the mechanical strain in the 3D-printed heterostructure was investigated. We envision that these 3D printed structures with 2DNs will lead to an evolution of next-generation optoelectronic, electronics and electromechanical devices, which would be printed on-demand.