Dual surface plasmon resonances in Ni nanoparticles in silica

Journal Article · Wed Jun 24 04:00:00 EDT 2015 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.4917656· OSTI ID:22490225

Majhi, Jayanta K. ^[1]

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1. Department of Physics, Banwarilal Bhalotia College, Asansol – 713303, West Bengal (India)

We report the observations of two broad absorption bands (at ∼3.5 and ∼6.0 eV) in the optical absorption (OA) spectra of Ni nanoparticles (NPs) in silica. For the calculations of the OA spectra, Maxwell-Garnett type effective medium theory has been used with NP radii in the range of 1 – 50 nm. The peak positions of both the OA bands have been found to shift towards higher energy (blue-shift) with decrease in NP radius. In addition, the OA spectra are found to more sensitive for smaller NPs as compare to larger NPs. These observations are argued as due to the confinement of the mean free path of free electrons in Ni NPs. Based on this, we conclude that the observed OA bands are due to the surface plasmon resonance (SPR) absorptions irrespective of the satisfaction of the criteria of the SPR conditions, thus resolving the unclear understanding of the appearance of two absorption bands in Ni NPs.

• OSTI ID: 22490225
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 1665; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABSORPTION SPECTRA
ABSORPTION SPECTROSCOPY
COMPARATIVE EVALUATIONS
ELECTRONS
EV RANGE
MEAN FREE PATH
NANOPARTICLES
NICKEL
SILICA
SURFACES