High-yield, sustainable ammonia synthesis from air and water with unprecedented efficiency via gas-phase electrochemical system

*This technology has been exclusively licensed for methods of forming nitrogen-based compounds*

This MAPS ammonia production technology uses hollow hybrid plasmonic nanocages to create a highly effective electrocatalyst for ammonia synthesis from nitrogen (N2) and water (H2O) under ambient temperatures and pressure in the gas- and liquid-phase system. As a major energy carrier and a critical ingredient in producing fertilizers, ammonia is widely produced globally. To meet these ammonia demands, Georgia Tech researchers have developed this sustainable and environmentally friendly production method that enables a high ammonia yield rate with unprecedented Faradaic and energy efficiency. This technology decentralizes the production of ammonia while consuming significantly less energy than current methods, permitting local or on-site production with renewable electricity sources and long-term energy storage.

Solution Advantages
  • Higher yield and efficiency: Uses hollow hybrid nanoparticles instead of solid nanoparticles for a three-fold enhancement in electrocatalytic activity due to the increased surface area and higher number of successful reactant collisions
  • Sustainable production: Leverages renewable electricity sources and offers clean and sustainable ammonia electrosynthesis, unlike the current industrial method for ammonia production that is energy intensive and heavily relies on fossil fuels
  • Simplified process: Enables production of ammonia via gas-phase system with few or no additional steps for separation and purification
  • Reduced carbon footprint: Enables decentralized production so that farmers can make their own fertilizer on site, eliminating the need to transport it
  • Long-term energy storage: Stored renewable energy in the form of liquid ammonia can be transported and delivered to end-users for various applications in the energy and transportation industries (e.g., back-up power, clean hydrogen fuel cells)
Potential Commercial Applications

This technology could optimize the production of ammonia for:

  • Clean energy storage and power generation
    • Storage of surplus renewable energy in the form of ammonia fuel at times of excess supply in the grid (energy storage)
    • Clean power generation
    • Ammonia fuel cells
    • Hydrogen fuel cells
  • Nitrogen-based fertilizers
  • Pharmaceutical industry (e.g., cleaning chemicals, etc.)
  • Marine industry
Background and More Information

Ammonia is the second most produced chemical in the world. The global production of ammonia approached approximately 146 million metric tons in 2015 and is projected to rise by 40% by 2050. In addition to fertilizers needed to increase food supply for the growing global population, Ammonia also holds great promise as a carbon-neutral liquid fuel for storing intermittent renewable energy when supply exceeds demand in the grid. It can also be used for power generation due to the compound’s high energy density and high hydrogen content. Ammonia can be utilized directly in ammonia fuel cells or indirectly in hydrogen fuel cells and plays a major role in the clean transportation sector.

Using the unique electrocatalytic activity of hollow hybrid plasmonic nanocages in a nitrogen reduction reaction, Georgia Tech created a new pathway to clean and sustainable ammonia electrosynthesis from N2 and H20 under ambient conditions using renewable electricity sources.

The method is a form of artificial synthesis that mimics the natural nitrogen enzymatic process. Georgia Tech researchers engineered the size and density of pores in the walls of the hollow plasmonic nanoparticles by tuning their peak localized surface plasmon resonance. In doing this, they enhanced the rate of electroreduction of nitrogen to ammonia. By increasing the temperature from 20˚C to 50˚C, an even greater electrocatalytic efficiency for ammonia synthesis is obtained.

Micro Ammonia Production System (MAPS)—Systems and methods for making nitrogen-based compounds

Schematic of the gas-phase (photo) electrochemical cell for nitrogen fixation using hybrid plasmonic nanocages. (center top) In this setup, the catalyst materials are painted on both sides of the membrane surface, as shown in the top right image. Note that the generated ammonia in the gas form will be liquefied using the condenser as depicted on the benchtop.