Synthesis of ammonia directly from wet air at intermediate temperature

For the first time, ammonia has been directly synthesised from wet air at intermediate temperature. Ce0.8Gd0.2O2−δ (CGO)–(Li,Na,K)2CO3 electrolyte together with a new perovskite oxide Pr0.6Ba0.4Fe0.8Cu0.2O3−δ were used for electrochemical synthesis of ammonia. An ammonia formation rate of 1.07 × 10−6 mol s−1 m−2 was obtained at 400 °C when applied a voltage of 1.4 V, while wet air was introduced to the single chamber reactor. This is just slightly lower than the value of 1.83 × 10−6 mol s−1 m−2 when wet N2 was fed under the same experimental conditions. These values are two to three orders of magnitude higher than the reported ammonia formation rates when synthesised from N2 and H2O at ∼600 °C. The perovskite catalysts are also low cost compared to the Ru/MgO and Pt/C catalysts in previous reports.