Magnetism of new metastable cobalt-nitride compounds. Issue 27 (6th June 2018)

• Record Type: Journal Article
• Authors: Balasubramanian, Balamurugan; Zhao, Xin; Valloppilly, Shah R.; Beniwal, Sumit; Skomski, Ralph; Sarella, Anandakumar; Jin, Yunlong; Li, Xingzhong; Xu, Xiaoshan; Cao, Huibo; Wang, Haohan; Enders, Axel; Wang, Cai-Zhuang; Ho, Kai-Ming; Sellmyer, David J.
• Is Part Of: Nanoscale. Volume 10:Issue 27(2018)
• Page Start: 13011
• Page End: 13021
• Publication Date: 2018-06-06
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/c8nr02105h
• Languages: English
• ISSNs: 2040-3364

Abstract

Abstract : New metastable hexagonal Co3 N structure and its magnetic transition shown by neutron diffraction. Abstract : The search for new magnetic materials with high magnetization and magnetocrystalline anisotropy is important for a wide range of applications including information and energy processing. There is only a limited number of naturally occurring magnetic compounds that are suitable. This situation stimulates an exploration of new phases that occur far from thermal-equilibrium conditions, but their stabilization is generally inhibited due to high positive formation energies. Here a nanocluster-deposition method has enabled the discovery of a set of new non-equilibrium Co–N intermetallic compounds. The experimental search was assisted by computational methods including adaptive-genetic-algorithm and electronic-structure calculations. Conventional wisdom is that the interstitial or substitutional solubility of N in Co is much lower than that in Fe and that N in Co in equilibrium alloys does not produce materials with significant magnetization and anisotropy. By contrast, our experiments identify new Co–N compounds with favorable magnetic properties including hexagonal Co3 N nanoparticles with a high saturation magnetic polarization ( J s = 1.28 T or 12.8 kG) and an appreciable uniaxial magnetocrystalline anisotropy ( K 1 = 1.01 MJ m −3 or 10.1 Mergs per cm 3 ). This research provides a pathway for uncovering new magnetic compounds with computational efficiency beyond the existing materials database, which is significant for future technologies.