The electrode layer is a critical component of low-temperature polymer electrolyte membrane electrochemical devices such as fuel cells and CO2 electrolyzers. The electrode has a major impact on the device’s efficiency, high current density performance and long-term durability. As such, the rational design and fabrication of electrode structures and interfaces with optimal component interactions, ionic and gas phase accessibility, as well as water management properties is crucial for advancing the performance, durability and economic viability of these electrochemical devices.Typically, membrane electrode assemblies are manufactured using fabrication techniques such as roll to roll, electrospinning or ultrasonic spray coating. These methods rely on homogenizing the catalysts, ionomers, solvents, and any other polymeric additives into a colloidal ink and depositing them onto a substrate. At the microscopic level, the combination of electrostatic repulsion and Van der Waals attraction between the individual constituents (solvent, catalyst, polymer) can alter the macroscopic properties (i.e. viscosity, surface tension, rheology) of the colloidal inks. These properties are relevant for coating and MEA manufacturing processes, as the net interparticle interaction potentials determine the tendency of particles to aggregate or disperse which impacts tortuosity, density and porosity of the deposited layer. .As such, optimizing component interactions is crucial for improving particle dispersion, drying behavior and stability of inks to fabricate high performance defect-free electrodes. Its imperative to expand our understanding of structure-property relationship between MEA composition and electrochemical characteristics (i.e. CO selectivity, HFR, mass/charge transport) to fabricate electrodes with high CO2 conversion efficiencies. Elucidating how composition (loading/thickness) morphology (porosity, surface roughness) and architecture (ionomer coverage, additives) of the catalyst layer and in turn its resulting impact on short term and long term performance will determine the commercial viability of CO2 electrolysis systems. This talk will highlight current R&D advancements in understanding of component interactions (i) for integrating high performance materials in electrodes for industrially relevant CO2 reduction applications, ii) improving electrode structure to maximize active site utilization and iii) mitigating mass transport limitations at catalyst-ionomer interface with a focus on understanding decay mechanisms.