Tailoring Electrical Properties in Carbon Nanomaterial Patterns with Multimaterial Aerosol Jet Printing.

Multimaterial aerosol jet printing offers a unique capability to freely mix inks with different chemical compositions in the aerosol phase, enabling one-step digital fabrication with tailored compositions or functionally graded structures, including in the plane. Here, in situ mixing of two carbon nanomaterial inks with distinct electrical properties is demonstrated. By tailoring the mixing ratio of the constituent inks, electrical conductivity is modulated by 130×, and sheet resistance values for a single pass span approximately 2 orders of magnitude.

Centrifuge-Free Separation of Solution-Exfoliated 2D Nanosheets via Cross-Flow Filtration.

Solution-processed graphene is a promising material for numerous high-volume applications including structural composites, batteries, sensors, and printed electronics. However, the polydisperse nature of graphene dispersions following liquid-phase exfoliation poses major manufacturing challenges, as incompletely exfoliated graphite flakes must be removed to achieve optimal properties and downstream performance. Incumbent separation schemes rely on centrifugation, which is highly energy-intensive and limits scalable manufacturing.

Systematic Design of a Graphene Ink Formulation for Aerosol Jet Printing.

Aerosol jet printing is a noncontact, digital, additive manufacturing technique compatible with a wide variety of functional materials. Although promising, development of new materials and devices using this technique remains hindered by limited rational ink formulation, with most recent studies focused on device demonstration rather than foundational process science. In the present work, a systematic approach to formulating a polymer-stabilized graphene ink is reported, which considers the effect of solvent composition on dispersion, rheology, wetting, drying, and phase separation characteristics that drive process outcomes.