Activating high-energy multiple bonds using earth-abundant metals is one of the most significant challenges in catalysis. Here, we show that LaCoSi—a ternary intermetallic compound—is an efficient and stable catalyst for N2 activation to produce NH3. The ammonia synthesis is significantly promoted by shifting the reaction bottleneck from the sluggish N2 dissociation to NH x formation, which few catalysts have achieved. Theoretical calculations reveal that the negatively charged cobalt mediates electron transfer from lanthanum to the adsorbed N2, which further reduces the activation barrier of N2 dissociation. Most importantly, the specific LaCoSi geometric configuration stabilizes the N2 adsorption with a strong exothermic effect, which dramatically decreases the apparent energy barrier of N2 activation. Consequently, LaCoSi shows a superior activity (1,250 μmol g−1 h−1), with a 60-fold increase over the activity of supported cobalt catalysts under mild reaction conditions (400 °C, 0.1 MPa).
Subscribe to Journal
Get full journal access for 1 year
only $8.25 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Tax calculation will be finalised during checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
Dumesic, J. A., Huber G. W. & Boudart, M. Handbook of Heterogeneous Catalysis (Wiley-VCH Verlag, Weinheim, 2008).
Huang, F., Liu, Z. Q. & Yu, Z. K. C-alkylation of ketones and related compounds by alcohols: transition-metal-catalyzed dehydrogenation. Angew. Chem. Int. Ed. 55, 862–875 (2016).
Han, F. S. Transition-metal-catalyzed Suzuki–Miyaura cross-coupling reactions: a remarkable advance from palladium to nickel catalysts. Chem. Soc. Rev. 42, 5270–5298 (2013).
Armbruster, M., Schlogl, R. & Grin, Y. Intermetallic compounds in heterogeneous catalysis—a quickly developing field. Sci. Technol. Adv. Mater. 15, 1–17 (2014).
Armbruster, M. et al. Pd–Ga intermetallic compounds as highly selective semihydrogenation catalysts. J. Am. Chem. Soc. 132, 14745–14747 (2010).
Armbrüster, M. et al. Al13Fe4 as a low-cost alternative for palladium in heterogeneous hydrogenation. Nat. Mater. 11, 690–693 (2012).
Erisman, J. W., Sutton, M. A., Galloway, J., Klimont, Z. & Winiwarter, W. How a century of ammonia synthesis changed the world. Nat. Geosci. 1, 636–639 (2008).
Gambarotta, S. & Scott, J. Multimetallic cooperative activation of N2. Angew. Chem. Int. Ed. 43, 5298–5308 (2004).
Pool, J. A., Lobkovsky, E. & Chirik, P. J. Hydrogenation and cleavage of dinitrogen to ammonia with a zirconium complex. Nature 427, 527–530 (2004).
Aika, K., Ozaki, A. & Hori, H. Activation of nitrogen by alkali metal promoted transition metal I. Ammonia synthesis over ruthenium promoted by alkali metal. J. Catal. 27, 424–431 (1972).
Ozaki, A. Development of alkali-promoted ruthenium as a novel catalyst for ammonia synthesis. Acc. Chem. Res. 14, 16–21 (1981).
Bielawa, H., Hinrichsen, O., Birkner, A. & Muhler, M. The ammonia-synthesis catalyst of the next generation: barium-promoted oxide-supported ruthenium. Angew. Chem. Int. Ed. 40, 1061–1063 (2001).
Ertl, G. Reactions at surfaces: from atoms to complexity (Nobel lecture). Angew. Chem. Int. Ed. 47, 3524–3535 (2008).
Rao, C. N. R. & Rao, G. R. Nature of nitrogen adsorbed on transition metal surfaces as revealed by electron spectroscopy and cognate techniques. Surf. Sci. Rep. 13, 221–263 (1991).
Ertl, G., Lee, S. B. & Weiss, M. Adsorption of nitrogen on potassium promoted Fe(111) and (100) surfaces. Surf. Sci. 114, 527–545 (1982).
Logadottir, A. & Norskov, J. K. Ammonia synthesis over a Ru(0001) surface studied by density functional calculations. J. Catal. 220, 273–279 (2003).
Kitano, M. et al. Electride support boosts nitrogen dissociation over ruthenium catalyst and shifts the bottleneck in ammonia synthesis. Nat. Commun. 6, 6731 (2015).
Wang, P. et al. Breaking scaling relations to achieve low-temperature ammonia synthesis through LiH-mediated nitrogen transfer and hydrogenation. Nat. Chem. 9, 64–70 (2017).
Inoue, Y. et al. Efficient and stable ammonia synthesis by self-organized flat Ru nanoparticles on calcium amide. ACS Catal. 6, 7577–7584 (2016).
Kitano, M. et al. Essential role of hydride ion in ruthenium-based ammonia synthesis catalysts. Chem. Sci. 7, 4036–4043 (2016).
Lu, Y. et al. Water durable electride Y5Si3: electronic structure and catalytic activity for ammonia synthesis. J. Am. Chem. Soc. 138, 3970–3973 (2016).
Kitano, M. et al. Ammonia synthesis using a stable electride as an electron donor and reversible hydrogen store. Nat. Chem. 4, 934–940 (2012).
Mizoguchi, H. et al. Hydride-based electride material, LnH2 (Ln = La, Ce, or Y). Inorg. Chem. 55, 8833–8838 (2016).
Hargreaves, J. S. J. Nitrides as ammonia synthesis catalysts and as potential nitrogen transfer reagents. Appl. Petrochem. Res. 4, 3–10 (2014).
Zeinalipour-Yazdi, C. D., Hargreaves, J. S. J. & Catlow, C. R. A. Nitrogen activation in a Mars–van Krevelen mechanism for ammonia synthesis on Co3Mo3N. J. Phys. Chem. C 119, 28368–28376 (2015).
Laassiri, S., Zeinalipour-Yazdi, C. D., Catlow, C. R. A. & Hargreaves, J. S. J. The potential of manganese nitride based materials as nitrogen transfer reagents for nitrogen chemical looping. Appl. Catal. B Environ. 223, 60–66 (2018).
Wu, J. et al. Tiered electron anions in multiple voids of LaScSi and their applications to ammonia synthesis. Adv. Mater. 29, 1700924 (2017).
Gupta, S. & Suresh, K. G. Review on magnetic and related properties of RTX compounds. J. Alloy. Compd 618, 562–606 (2015).
Welter, R., Venturini, G., Ressouche, E. & Malaman, B. Magnetic properties of RCoSi (R = La–Sm, Gd, Tb) compounds from susceptibility measurements and neutron diffraction studies. J. Alloy. Compd. 210, 279–286 (1994).
Liu, G. et al. MoS2 monolayer catalyst doped with isolated Co atoms for the hydrodeoxygenation reaction. Nat. Chem. 9, 810–816 (2017).
Zhou, J. et al. Synthesis of Co–Sn intermetallic nanocatalysts toward selective hydrogenation of citral. J. Mater. Chem. A 4, 12825–12832 (2016).
Deng, D. et al. A single iron site confined in a graphene matrix for the catalytic oxidation of benzene at room temperature. Sci. Adv. 1, e1500462 (2015).
Yano, J. & Yachandra, V. K. X-ray absorption spectroscopy. Photosynth. Res. 102, 241–254 (2009).
Tang, W., Sanville, E. & Henkelman, G. A grid-based Bader analysis algorithm without lattice bias. J. Phys. Condens. Matter 21, 084204 (2009).
Kakuta, H., Ogawa, T., Takamura, H. & Okada, M. Protium absorption properties of La–TM–Si (TM = Co, Ni) ternary intermetallic compounds. Mater. T. Jim. 39, 769–772 (1998).
Liu, H. Ammonia synthesis catalyst 100 years: practice, enlightenment and challenge. Chin. J. Catal. 35, 1619–1640 (2014).
Kojima, R. & Aika, K. Cobalt molybdenum bimetallic nitride catalysts for ammonia synthesis: Part 1. Preparation and characterization. Appl. Catal. A 215, 149–160 (2001).
Kojima, R. & Aika, K. Cobalt molybdenum bimetallic nitride catalysts for ammonia synthesis: Part 2. Kinetic study. Appl. Catal. A 218, 121–128 (2001).
Takeshita, T., Wallace, W. E. & Craig, R. S. Rare earth intermetallics as synthetic ammonia catalysts. J. Catal. 44, 236–243 (1976).
Hagen, S. et al. Ammonia synthesis with barium-promoted iron–cobalt alloys supported on carbon. J. Catal. 214, 327–335 (2003).
Aika, K. et al. Support and promoter effect of ruthenium catalyst. III. Kinetics of ammonia synthesis over various Ru catalysts. Appl. Catal. 28, 57–68 (1986).
Kobayashi, Y., Kitano, M., Kawamura, S., Yokoyama, T. & Hosono, H. Kinetic evidence: the rate-determining step for ammonia synthesis over electride-supported Ru catalysts is no longer the nitrogen dissociation step. Catal. Sci. Technol. 7, 47–50 (2017).
Jacobsen, C. J. H. et al. Catalyst design by interpolation in the periodic table: bimetallic ammonia synthesis catalysts. J. Am. Chem. Soc. 123, 8404–8405 (2001).
Wang, J. J. et al. Adsorption of atomic and molecular oxygen on 3C-SiC(111) and (111) surfaces: a first-principles study. Phys. Rev. B 79, 125304 (2009).
Vojvodic, A. et al. Exploring the limits: a low-pressure, low-temperature Haber–Bosch process. Chem. Phys. Lett. 598, 108–112 (2014).
Ravel, B. & Newville, M. ATHENA, ARTEMIS, HEPHAESTUS: data analysis for X-ray absorption spectroscopy using IFEFFIT. J. Synchrotron Radiat. 12, 537–541 (2005).
Zabinsky, S. I., Rehr, J. J., Ankudinov, A., Albers, R. C. & Eller, M. J. Multiple-scattering calculations of x-ray-absorption spectra. Phys. Rev. B 52, 2995–3009 (1995).
Siporin, S. E. & Davis, R. J. Use of kinetic models to explore the role of base promoters on Ru/MgO ammonia synthesis catalysts. J. Catal. 225, 359–368 (2004).
Kresse, G. & Furthmuller, J. Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set. Comp. Mater. Sci. 6, 15–50 (1996).
Kresse, G. & Furthmuller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54, 11169–11186 (1996).
Perdew, J. P., Burke, K. & Ernzerhof, M. Generalized gradient approximation made simple. Phys. Rev. Lett. 77, 3865–3868 (1996).
This work was supported by the Accelerated Innovation Research Initiative Turning Top Science and Ideas into High-Impact Values (ACCEL) programme of the Japan Science and Technology Agency. H.H. was supported by the Japan Society for the Promotion of Science through a Grant-in-Aid for Scientific Research (S), No.17H06153. The authors thank S. Fujitsu (Tokyo Institute of Technology) for technical support with the Auger electron spectroscopy measurements.
The authors declare no competing financial interests.
Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
About this article
Cite this article
Gong, Y., Wu, J., Kitano, M. et al. Ternary intermetallic LaCoSi as a catalyst for N2 activation. Nat Catal 1, 178–185 (2018). https://doi.org/10.1038/s41929-017-0022-0
Nature Nanotechnology (2021)
Insight into dynamic and steady-state active sites for nitrogen activation to ammonia by cobalt-based catalyst
Nature Communications (2020)
Nitrogen reduction reaction on small iron clusters supported by N-doped graphene: A theoretical study of the atomically precise active-site mechanism
Nano Research (2020)
Over 56.55% Faradaic efficiency of ambient ammonia synthesis enabled by positively shifting the reaction potential
Nature Communications (2019)