Alternative green and cost-effective processes for ammonia production.
Ammonia (NH3) production via the Haber–Bosch process was one of the key achievements of the 20th century, enabling quadrupling the production of agricultural products and acting as a preventive measure to stop world hunger. It is estimated that between a third to a half of the world population would suffer starvation if ammonia-based fertilisers were not available. Ammonia is also an excellent indirect hydrogen-storage material as it is more energy efficient to produce, store, and deliver hydrogen as ammonia than as compressed and/or cryogenic hydrogen. Ammonia is also seen as an eco-friendly energy source for a sustainable energy future as it can be synthesised directly from atmospheric nitrogen and does not produce CO2 during burning. However, the industrial production of ammonia is very energy intensive (2% of global energy consumption), requiring high temperature (500◦C) and pressure (in excess of 500 atmospheres), and very pure raw materials; it is also eco-destructive (creating more than 900 million tonnes of CO2 by-product per year), costly and requires considerable plant infrastructure. As such, there is an immediate need to develop alternative green and cost-effective processes for ammonia production.
Ammonia can be produced at room temperature by electrochemical synthesis. However, all of the state-of-art systems have common limitations such as slow kinetics of the transformation, expensive electrolytes, high pressure & temperature (to increase the kinetics), poor selectivity, low conversion rate and low Faradaic efficiency.