SIGNATURE WORK
CONFERENCE & EXHIBITION 2022

The fabrication of conductive three-dimensional (3D) structures is of great interest for electrochemical applications, include the creation of high sensitivity electrochemical sensors and high-capacity batteries. Current fabrication methods to fabricate conductive 3D structures frequently utilize templates that are removed in post-processing, creating additional fabrication steps and environmentally hazardous waste. In this work, aerosol jet printing is utilized to fabricate conductive 3D structures out of recyclable graphene ink without the need for templates or structural post-processing. Graphene is printed due to its high theoretical specific area (2630 m2/g), its prevalence as a sensor material, and its demonstrated recyclability. Graphene ink composition and printing conditions are developed to realize free-form fabrication of 3D graphene structures via aerosol jet printing. We report pillars and 2-member trusses with heights of 500-2000 micron and diameters of 50-100 microns, printed on both paper and glass substrates. Two-terminal conductance in the truss structures is 2.87 ± 1.98 kΩ over 111 measurements. Additionally, we report post-print treatments to prevent the dissolution of pillars in aqueous solution and application of graphene pillars to an electrochemical sensing platform.