Nanostructured Fe-doped La_0.3Sr_0.7TiO_3-δ/Ce_0.8Gd_0.18Ca_0.02O_2-δ nanocomposite for electrocatalytic ammonia synthesis from humid N₂

Abstract:

The development of sustainable ammonia synthesis methods is crucial for reducing the environmental impact of the energy-intensive Haber–Bosch process. However, creating efficient and cost-effective electrocatalysts for ammonia synthesis remains a significant challenge, primarily due to competition from the hydrogen evolution reaction (HER), which diverts current away from ammonia production and reduces Faradaic efficiency. This study investigates the electrocatalytic performance of a La₀.₃Sr₀.₇Ti₀.₈Fe₀.₂O₃-_δ and Ce₀.₈Gd₀.₁₈Ca₀.₀₂O₂-_δ (LSTF–CGDC) composite cathode for green ammonia production from humid nitrogen (3% H₂O) under ambient pressure. Synthesized via a sol–gel method and characterized using X-ray diffraction (XRD), the composite exhibited high structural stability and phase compatibility. Ammonia synthesis was achieved across a temperature range of 375–450 °C and applied voltages of 1.2–1.8 V, with a peak production rate of 4.0 × 10⁻¹¹ mol s⁻¹ cm⁻² at 425 °C and 1.4 V. Despite these promising results, the Faradaic efficiency remained low (~0.07%) due to persistent HER competition. This study underscores the potential of non-noble perovskite-based catalysts for sustainable ammonia production and highlights the need for further optimization in both selectivity and efficiency.

• Periodical: Journal of Nano Research (Volume 90)
• Pages: 69-84
• DOI: https://doi.org/10.4028/p-OAZQ3l
• Online since: December 2025
• Authors: Ibrahim A. Amar*, Abubaker A. Sharif
• Keywords: Electrocatalytic Ammonia Synthesis, Electrocatalytic Energy Efficiency, Fe-Doped Perovskite Oxides, Green Ammonia Production, Nitrogen Reduction Reaction, Non-Noble Metal Electrocatalysts

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