To study the relatively novel technology of anion exchange membrane (AEM) water electrolysis in a scientific manner, a controllable and repeatable electrode fabrication method is needed. While inkjet printing has been successfully used to fabricate electrodes for proton exchange membrane (PEM) water electrolyzers, it has not been used for fabricating AEM-based water electrolyzer electrodes. The drop-on-demand nature of inkjet printing allows for the precise control of the electrode fabrication process such that the electrode loadings may be precisely controlled. This work investigates the suitability of the inkjet printing method for fabricating electrodes for AEM-based water electrolysis.

Catalyst inks based upon Pt|C and IrOx were developed containing a commercially available anion conducting ionomer. The suitability of the catalyst inks for use with the inkjet printing method was analyzed using dynamic light scattering (DLS) and glass kinematic viscometers. The consistency of the inks, as determined from DLS, was improved by decreasing the wt.% of the ionomer solution used to produce the inks, and by adding a viscosity increasing additive (propylene glycol) to the catalyst ink slurry after the addition of the ionomer.

The developed catalyst inks were successfully used to produce and test AEM-based water electrolyzers with catalyst coated membrane (CCM) and catalyst coated substrate (CCS) cell architectures. While the loading normalized performance for the cells was found to be similar to those from literature at low operational currents, it was notably poorer at elevated currents. Using electrochemical impedance spectrometry (EIS) it was found that the cell resistances were similar to or even lower than those from literature. The lower cell performance was therefore hypothesized to be due to the relatively high anodic ionomer content used (15 wt.% compared to 7 wt.% used in literature). While it was found that the inkjet printing method is suitable for producing electrodes for AEM-based water electrolysis, further testing is required with anion conducting materials (membrane and ionomer) that are less prone to dimensional swelling due to water uptake to obtain cell-to-cell repeatability.