Sabrina C. Zignani, Alessandra Carbone, Angela Salanitro, Mariarosaria Pascale, Vitaliano Chiodo, Susanna Maisano, Natale Mondello, Giovanni Frisone, Giuseppe Monforte, Antonino S. Aricò (CNR-ITAE), Luca Riillo, Anna Ramunni (DE NORA), Tim De Serrano (BEKAERT), Charly Azra, Ervintal Gutelmacher (HYDROLITE), Joost Helse, Jing Shen, Swapnil Verhade (VITO)
Abstract
The D5.3 deliverable report of ECO2Fuel deals with the development of membrane-electrodes assemblies (MEAs) with enhanced performance and stability for electrolysis of CO2 to form carbonaceous fuels. An intermediate goal of the project was to select the most promising MEA configuration according to the achieved results in terms of electrochemical performance, stability and faradaic efficiency.
The down-selected electrocatalysts were a NiFe-layered double hydroxide (LDH) anode developed by CNR and a CuOx cathode developed by UPV. Both catalysts were scaled-up by Monolithos. Promising electrochemical activity and stability were achieved for low temperature CO2 electrolysis by combining these electro-catalysts with a Hydrolite Anion exchange membrane (AEM). Specifically, the Hydrolite GEN 2 AEM developed in the project favorably compared to benchmark membranes. For the electrodes, a catalyst coated substrate configuration was selected by De Nora and a cold assembling procedure was adopted at CNR and VITO to form membrane-electrode assemblies. Ni densified top layer from Bekaert was used for the anode and a hydrophobic carbonaceous diffusion layer for the cathode. The latter was selected to suppress hydrogen evolution reaction (HER) and enhance formation of carbonaceous products. The results were approaching the project objectives for the faradaic efficiency of carbonaceous fuels and voltage efficiency as well as for the stability. Accordingly, the ECO2Fuel cell concept for low-temperature co-electrolysis of CO2 and water forming both gas and liquid carbonaceous fuels was demonstrated at the single cell level. A significant issue related to the clogging of the cathode pores in durability tests was mitigated by specific technical solutions. A long term durability test exceeding 800 hours was carried out and the cathode outlet stream composition was determined by gas chromatography. The developed electrocatalysts were compared to benchmarks showing enhanced activity.
