ESPRESSO-NANO: Electrospray assisted Spark Process for Rapid Electrocatalyst Synthesis and Optimization of NANOparticles

The growing energy demand and environmental impact of traditional sources highlight the need for sustainable solutions. Hydrogen produced through water electrolysis, is a flexible and clean energy carrier capable of addressing large-electricity storage needs of the renewable but intermittent energy sources. Among various technologies, Proton Exchange Membrane Water Electrolysis (PEMWE) stands out for its efficiency and rapid response, making it ideal for grid stabilization. In its core, PEMWEs are composed of membrane electrode assemblies (MEA), which consist of a proton-conducting membrane sandwiched between two catalyst-coated electrodes, forming a single PEMWE cell unit. Despite the high efficiency and low emissions, a principal drawback of PEMWE is the capital cost due to high loading of precious metal catalysts and protective coatings. Traditional MEA catalyst coating methods are complex, inefficient, and costly to scale. To circumvent these challenges, VSParticle developed a technology for nanoparticle film production using spark ablation, which generates nanoparticles through high-voltage discharges between electrodes followed by an impaction printing module. However, the absence of liquids poses challenges, such as integrating polymeric solutions (e.g., Nafion®) for uniform, thicker catalyst coatings. Electrohydrodynamic atomization (EHDA) stands out as a promising technique thanks to its strong electric fields used to generate micro- and nanometric droplets with a narrow size distribution. Co-axial EHDA, a variation of this technique, utilizes two concentric needles to spray different fluids simultaneously.The ESPRESSO-NANO project combines co-axial EHDA with spark ablation to improve catalyst uniformity and performance at the nanometer scale by integrating electrosprayed ionomer nanoparticles with dry metal nanoparticles, ensuring better distribution of the catalyst within the nanoporous layer. This novel approach streamlines numerous steps in traditional synthesis and electrocatalyst film production which will address material waste and energy consumption, while simultaneously improve the electrochemical efficiency of PEMWEs, offering a sustainable solution to the global energy crisis.