(653e) Electrocatalytic Synthesis of Ammonia on Composite Bimetallic Nitride-Perovskite Oxide Soec Cathode
AIChE Annual Meeting
Thursday, November 17, 2022 - 4:49pm to 5:07pm
In this study, a composite SOEC cathode of the perovskite (La0.6Sr0.4)0.95Co0.2Fe0.8O3 (LSCF) and the nitride Co3Mo3N was fabricated, and its activity for NRR was studied. A layer of LSCF was sintered on both sides of the YSZ electrolyte, and a mixture of Co3Mo3N and LSCF was deposited on the cathode side. During NRR, 3% H2O/N2 was supplied to the cathode at 500â600Â°C with applied current densities of 0â2 mA/cm2. NRR activity was quantified, and the measured production rates were corrected by Ar and OCV control experiments. The composite cathode performed significantly better than the pure perovskite cathode or pure Co3Mo3N cathode, indicating a synergistic relationship between the two materials. These results imply that Co3Mo3N increases the rate of nitrogen activation, while the ionic/electronic conduction properties of LSCF improve the overall cell performance. Relevant properties of Co3Mo3N were analyzed such as electronic conductivity, stability in the reaction environment, and mobility of nitrogen ions. Co3Mo3N was characterized by inÂ-situ XRD, NAP-XPS, XANES, and temperature-programmed experiments.
Few non-noble metal materials have been identified as effective electrochemical NRR catalysts for the high-temperature range. The activity and stability of Co3Mo3N and its compatibility with proven perovskite catalysts allow for this unique composite cathode approach to high temperature NH3 production.