3D Printing for catalytic activity – Ink development using a drop-on-demand cartridge

Abstract

Powder-bed binder-jetting 3D printing requires the use of a liquid binder or ink. These binders/inks have been widely tailored for individual application. This article covers the proof-of-concept development of an ink for a powder-bed binder-jetting 3D printer. The ink formulation in our work is both catalytically active and is used to bind the catalyst substrate. A modified, commercially available inkjet cartridge is used to spread liquid ink onto a powder surface, forming shapes in a layer-wise fashion to produce green bodies that are heat-treated post-print. The important parameters for manipulating rheology for inkjet printing are explored as a function of ink formulation. Specifically, the relationship between density, viscosity, and surface tension dictates the suitability for printing and those properties can be controlled by using differing amounts of the ink’s constituent components. Relationships correlating density to solvent concentration and viscosity to binder and dispersant concentrations are found, which are used to determine a water-based ink formulation suitable for use in the commercially available ink cartridge. The results of an initial print are presented and show excellent dispersion of the nickel catalyst.