Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Structural and magnetic properties of cobalt iron disulfide (CoxFe1-xS2) nanocrystals

Journal Article · · Scientific Reports

We report on synthesis and investigation of nanocrystalline cobalt-iron-pyrites with an emphasis on nanocrystal structure, morphology and magnetic behavior. The nanocrystals (NCs) were 5–25 nm in diameter as characterized using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). With an increase in Fe fraction, X-ray diffraction and small-angle-X-ray scattering (SAXS) showed a systematic decrease in lattice constant, primary grain/NC size (15 to 7 nm), and nanoparticle (NP) size (70 to 20 nm), respectively. The temperature dependence of the DC magnetization and AC susceptibility versus frequency revealed a number of magnetic phases in CoxFe1-xS2. Samples with x = 1 and x = 0.875–0.625 showed evidence of superspin glass (SSG) behavior with embedded ferromagnetic (FM) clusters of NPs. For x = 0.5, samples retained their mixed phases, but showed superparamagnetic (SPM) behavior with antiferromagnetic clusters suppressing magnetic dipolar interactions. Below x = 0.5, the pyrites show increasing paramagnetic character. We construct a phase diagram, which can be understood in terms of competition between the various dipolar, exchange, inter- and intracluster interactions. Our results suggest that NC size and shape can be tuned to engineer spin-polarized ferromagnetism of n-doped iron pyrite.

Research Organization:
Univ. of California, Irvine, CA (United States)
Sponsoring Organization:
USDOE
Grant/Contract Number:
EE0005324
OSTI ID:
1500211
Journal Information:
Scientific Reports, Journal Name: Scientific Reports Journal Issue: 1 Vol. 8; ISSN 2045-2322
Publisher:
Nature Publishing GroupCopyright Statement
Country of Publication:
United States
Language:
English

References (23)

Iron disulfide for solar energy conversion journal May 1993
The HighScore suite journal October 2014
Majority Carrier Type Control of Cobalt Iron Sulfide (Co x Fe 1– x S 2 ) Pyrite Nanocrystals journal January 2016
Effect of Disorder and Dipolar Interactions in Two-Dimensional Assemblies of Iron-Oxide Magnetic Nanoparticles journal March 2016
Colloidal Iron Pyrite (FeS 2 ) Nanocrystal Inks for Thin-Film Photovoltaics journal February 2011
Spin-glass-like freezing of inner and outer surface layers in hollow γ-Fe2O3 nanoparticles journal October 2015
Origin of reduced magnetization and domain formation in small magnetite nanoparticles journal April 2017
Magnetic properties of Co3O4 nanoparticles mineralized in Listeria innocua Dps journal April 2006
Magnetic coupling induced increase in the blocking temperature of γ-Fe2O3 nanoparticles journal May 2000
Standardisation of magnetic nanoparticles in liquid suspension journal August 2017
Superferromagnetic domain state of a discontinuous metal insulator multilayer journal July 2005
Dynamics of spin clusters in amorphous Fe 2 O 3 journal November 2005
Charge transport in cobalt-doped iron pyrite journal April 2010
Superspin glass originating from dipolar interaction with controlled interparticle distance among γ -Fe 2 O 3 nanoparticles with silica shells journal June 2011
Structural and magnetic properties of CoO-Pt core-shell nanoparticles journal March 2014
Exchange-bias-like coupling in a Cu-diluted-Fe/Tb multilayer journal March 2015
Dynamics of an Interacting Particle System: Evidence of Critical Slowing Down journal December 1997
A profile refinement method for nuclear and magnetic structures journal June 1969
Determination of size distribution from small-angle scattering data for systems with effective hard-sphere interactions journal August 1994
A customizable software for fast reduction and analysis of large X-ray scattering data sets: applications of the new DPDAK package to small-angle X-ray scattering and grazing-incidence small-angle X-ray scattering journal September 2014
Superparamagnetism and Other Magnetic Features in Granular Materials: A Review on Ideal and Real Systems journal June 2008
Structural and magnetic properties of CoO-Pt core-shell nanoparticles text January 2014
Structural and Magnetic Properties of CoO-Pt core-shell nanoparticles text January 2013

Cited By (1)

Topologically stable helices in exchange coupled rare-earth/rare-earth multilayer with superspin-glass like ordering journal September 2019

Similar Records

Magnetic Behavior of Iron-Rich Permalloy Nanoparticles
Journal Article · Sun Jul 15 00:00:00 EDT 2018 · Journal of Superconductivity and Novel Magnetism · OSTI ID:22773967

Magnetic and electrocatalytic properties of transition metal doped MoS2 nanocrystals
Journal Article · Wed Oct 17 00:00:00 EDT 2018 · Journal of Applied Physics · OSTI ID:1481874

Simple solvothermal synthesis of hydrophobic magnetic monodispersed Fe{sub 3}O{sub 4} nanoparticles
Journal Article · Thu Feb 14 23:00:00 EST 2013 · Materials Research Bulletin · OSTI ID:22215812

Related Subjects