, Volume 58, Issue 2, pp 371–383 | Cite as

Arrays of magnetic nanoparticles capped with alkylamines

  • P John Thomas
  • P Saravanan
  • G U Kulkarni
  • CNR RaoEmail author


Magnetic metal and metal oxide nanoparticles capped with alkylamines have been synthesized and characterized by transmission electron microscopy. X-ray diffraction, energy dispersive X-ray analysis and magnetization measurements. Core-shell Pd-Ni particles with composition, Pd561Ni3000, (diameter ∼3.3 nm) are superparamagnetic at 5 K and organize themselves into two-dimensional crystalline arrays. Similar arrays are obtained with Pd561Ni3000Pd1500 nanoparticles containing an additional Pd shell. Magnetic spinel particles of γ-Fe2O3, Fe3O4 and CoFe2O4 of average diameters in the 4–6 nm range coated with octylamine are all supermagnetic at room temperature and yield close-packed disordered arrays. Relatively regular arrays are formed by dodecylaminecapped Fe3O4 nanoparticles (∼8.6 nm diameter) while well-ordered hexagonal arrays were obtained with octylamine-covered Co3O4 nanoparticles (∼4.2 nm diameter).


Self-assembly magnetic nanoparticles 


81.16.D 81.07.Bc 81.16.B 


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Copyright information

© Indian Academy of Sciences 2002

Authors and Affiliations

  • P John Thomas
    • 1
  • P Saravanan
    • 1
  • G U Kulkarni
    • 1
  • CNR Rao
    • 1
    Email author
  1. 1.Chemistry and Physics of Materials UnitJawaharlal Nehru Centre for Advanced Scientific Research, JakkurBangaloreIndia

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