Iron nitrides

Chemical compound made of iron and nitrogen

Iron nitrides are inorganic chemical compounds of iron and nitrogen.

Chemical properties

Iron has five nitrides observed at ambient conditions, Fe₂N, Fe₃N₄, Fe₄N, Fe₇N₃ and Fe₁₆N₂. They are crystalline, metallic solids. Group 7 and group 8 transition metals form nitrides that decompose at relatively low temperatures – iron nitride, Fe₂N decomposes with loss of molecular nitrogen at around 400 °C and formation of lower-nitrogen content iron nitrides. They are insoluble in water. At high pressure, stability and formation of new nitrogen-rich nitrides (N/Fe ratio equal or greater to one) were suggested^[1] and later discovered. These include the FeN, FeN₂ and FeN₄ solids which become thermodynamically stable above 17.7 GPa, 72 GPa and 106 GPa, respectively.^[2]^[3]^[4]^[5]^[6]

Health hazards

When heated to decomposition or exposed to humidity, iron nitride may emit toxic fumes of ammonia. It is considered a moderate explosion hazard. Inhalation of iron nitride dust or powder may cause irritation to the respiratory system and possibly acute iron poisoning or pneumoconiosis.

Research applications

Colloidal solution of magnetic iron nitride nanoparticles is a way to create ferrofluids.

Iron nitrides also make the strongest naturally magnetic material.^[7]^[8]^[9]

References

^ Kartsev, Alexey (2015). Thermodynamic Properties of NiAs-FeN Phase from First Principles. Destech Publicat, Inc. pp. 423–427. arXiv:1807.09900. ISBN 978-1-60595-112-6.
^ Laniel, Dominique; Dewaele, Agnès; Anzellini, Simone; Guignot, Nicolas (2018-02-05). "Study of the iron nitride FeN into the megabar regime". Journal of Alloys and Compounds. 733: 53–58. doi:10.1016/j.jallcom.2017.10.267. ISSN 0925-8388.
^ Niwa, Ken; Terabe, Toshiki; Kato, Daiki; Takayama, Shin; Kato, Masahiko; Soda, Kazuo; Hasegawa, Masashi (2017-05-16). "Highly Coordinated Iron and Cobalt Nitrides Synthesized at High Pressures and High Temperatures". Inorganic Chemistry. 56 (11): 6410–6418. doi:10.1021/acs.inorgchem.7b00516. ISSN 0020-1669. PMID 28509545.
^ Clark, William P.; Steinberg, Simon; Dronskowski, Richard; McCammon, Catherine; Kupenko, Ilya; Bykov, Maxim; Dubrovinsky, Leonid; Akselrud, Lev G.; Schwarz, Ulrich (18 May 2017). "High-Pressure NiAs-Type Modification of FeN". Angewandte Chemie International Edition. 56 (25): 7302–7306. doi:10.1002/ANIE.201702440. ISSN 1433-7851. PMC 5488211. PMID 28517174. Wikidata Q36374759.
^ Laniel, Dominique; Dewaele, Agnès; Garbarino, Gaston (2018-03-05). "High Pressure and High Temperature Synthesis of the Iron Pernitride FeN2". Inorganic Chemistry. 57 (11): 6245–6251. doi:10.1021/acs.inorgchem.7b03272. ISSN 0020-1669. PMID 29505253.
^ Bykov, M.; Bykova, E.; Aprilis, G.; Glazyrin, K.; Koemets, E.; Chuvashova, I.; Kupenko, I.; McCammon, C.; Mezouar, M. (16 July 2018). "Fe-N system at high pressure reveals a compound featuring polymeric nitrogen chains". Nature Communications. 9 (1): 2756. Bibcode:2018NatCo...9.2756B. doi:10.1038/S41467-018-05143-2. ISSN 2041-1723. PMC 6048061. PMID 30013071. Wikidata Q55692060.
^ "Iron-nitrogen compound forms strongest magnet known".
^ Aravindh, S. Assa; Nokelainen, Johannes; Barbiellini, Bernardo; Alatalo, Matti; Murali, D.; Bansil, Arun (2022). "Re-examining the giant magnetization density in α′′-Fe16N2 with the SCAN + U method". Phys. Chem. Chem. Phys. 24 (29): 17879–84. Bibcode:2022PCCP...2417879D. doi:10.1039/D2CP01734B. PMID 35851914.
^ Cui, J.; Kramer, M.; Zhou, L.; Liu, F.; Gabay, A.; Hadjipanayis, G.; Balasubramanian, B.; Sellmyer, D. (2018). "Current progress and future challenges in rare-earth-free permanent magnets". Acta Materialia. 158: 118–137. Bibcode:2018AcMat.158..118C. doi:10.1016/j.actamat.2018.07.049. §9. Iron nitride (ɑ″-Fe16N2)