Ferromagnetism Exhibited by Nanoparticles of Noble Metals

Maitra, Urmimala ; Das, Barun ; Kumar, Nitesh ; Sundaresan, Athinarayanan ; Rao, C. N. R. (2011) Ferromagnetism Exhibited by Nanoparticles of Noble Metals ChemPhysChem, 12 (12). pp. 2322-2327. ISSN 1439-4235

Full text not available from this repository.

Official URL: http://doi.org/10.1002/cphc.201100121

Related URL: http://dx.doi.org/10.1002/cphc.201100121


Gold nanoparticles with average diameters in the range 2.5–15 nm, prepared at the organic/aqueous interface by using tetrakis(hydroxymethyl)phosphonium chloride (THPC) as reducing agent, exhibit ferromagnetism whereby the saturation magnetization MS increases with decreasing diameter and varies linearly with the fraction of surface atoms. The value of MS is higher when the particles are present as a film instead of as a sol. Capping with strongly interacting ligands such as alkane thiols results in a higher MS value, which varies with the strength of the metal–sulfur bond. Ferromagnetism is also found in Pt and Ag nanoparticles prepared as sols, and the MS values vary as Pt>Au>Ag. A careful study of the temperature variation of the magnetization of Au nanoparticles, along with certain other observations, suggests that small bare nanoparticles of noble metals could indeed possess ferromagnetism, albeit weak, which is accentuated in the presence of capping agents, specially alkane thiols which form strong metal–sulfur bonds.

Item Type:Article
Source:Copyright of this article belongs to John Wiley and Sons, Inc.
ID Code:120056
Deposited On:22 Jun 2021 05:40
Last Modified:22 Jun 2021 05:40

Repository Staff Only: item control page