Efficient Ammonia Electrosynthesis from Nitrate on Strained Ruthenium Nanoclusters
Citations Over TimeTop 1% of 2020 papers
Abstract
The limitations of the Haber-Bosch reaction, particularly high-temperature operation, have ignited new interests in low-temperature ammonia-synthesis scenarios. Ambient N2 electroreduction is a compelling alternative but is impeded by a low ammonia production rate (mostly cat-1 h-1), a small partial current density (-2), and a high-selectivity hydrogen-evolving side reaction. Herein, we report that room-temperature nitrate electroreduction catalyzed by strained ruthenium nanoclusters generates ammonia at a higher rate (5.56 mol gcat-1 h-1) than the Haber-Bosch process. The primary contributor to such performance is hydrogen radicals, which are generated by suppressing hydrogen-hydrogen dimerization during water splitting enabled by the tensile lattice strains. The radicals expedite nitrate-to-ammonia conversion by hydrogenating intermediates of the rate-limiting steps at lower kinetic barriers. The strained nanostructures can maintain nearly 100% ammonia-evolving selectivity at >120 mA cm-2 current densities for 100 h due to the robust subsurface Ru-O coordination. These findings highlight the potential of nitrate electroreduction in real-world, low-temperature ammonia synthesis.
Related Papers
- → Anionic ruthenium cluster K2[Ru4(CO)13] as precursor of catalytically active ruthenium particles and potassium promoter. New efficient ammonia synthesis catalysts based on supported K2[Ru4(CO)13](1998)19 cited
- → Basic concepts and properties of new generation ammonia synthesis catalysts for industrial use(1999)9 cited
- Activity influence factors of ruthenium catalysts supported on MO_x for ammonia synthesis(2011)
- Evaluation of iron catalyst coupled with ruthenium tandem catalyst in ammonia synthesis(2007)
- Recent progress in ammonia synthesis catalysts(2005)