Electrochemical ammonia synthesis has been demonstrated in numerous different systems, involving many types of electrolytes.3–7 However most studies report current efficiencies of 10% or less. This highlights the challenge of reducing N2 in the presence of more easily reducible species. On this basis, it should be possible to improve both the rate and efficiency by developing new catalysts which can selectively reduce nitrogen, but not other species.
In this work, BaCe0.2Zr0.7Y0.1O3-δ perovskite proton conductor-based electrolysis cells are studied for application of reduction of nitrogen gas to ammonia. Specifically, we focus on modifying electrodes to improve the cell performance. Some interesting results have already been obtained, showing drastically different currents when designing electrodes from mixed-metal systems. These currents, however, do not seem to translate into improved synthesis rates, which is also explored.
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