Next Article in Journal
Single Molecule Fluorescence Detection and Tracking in Mammalian Cells: The State-of-the-Art and Future Perspectives
Previous Article in Journal
Biological Activities of Toninia candida and Usnea barbata Together with Their Norstictic Acid and Usnic Acid Constituents
Int. J. Mol. Sci. 2012, 13(11), 14723-14741; doi:10.3390/ijms131114723
Article

Influence of Dose on Particle Size and Optical Properties of Colloidal Platinum Nanoparticles

 and *
Received: 17 September 2012; in revised form: 3 November 2012 / Accepted: 4 November 2012 / Published: 12 November 2012
(This article belongs to the Section Material Sciences and Nanotechnology)
View Full-Text   |   Download PDF [718 KB, uploaded 19 June 2014]   |   Browse Figures
Abstract: Attempts to produce colloidal platinum nanoparticles by using steady absorption spectra with various chemical-based reduction methods often resulted in the fast disappearance of the absorption maxima leaving reduced platinum nanoparticles with little information on their optical properties. We synthesized colloidal platinum nanoparticles in an aqueous solution of polyvinyl pyrrolidone by gamma radiolytic reduction method, which produced steady absorption spectra of fully reduced and highly pure platinum nanoparticles free from by-product impurities or reducing agent contamination. The average particle size was found to be in the range of 3.4–5.3 nm and decreased with increasing dose due to the domination of nucleation over ion association in the formation of metal nanoparticles by the gamma radiolytic reduction method. The platinum nanoparticles exhibit optical absorption spectra with two absorption peaks centered at about 216 and 264 nm and the peaks blue shifted to lower wavelengths with decreasing particle size. The absorption spectra of platinum nanoparticles were also calculated using quantum mechanical treatment and coincidently a good agreement was obtained between the calculated and measured absorption peaks at various particle sizes. This indicates that the 216 and 264-nm absorption peaks of platinum nanoparticles conceivably originated from the intra-band transitions of conduction electrons of (n = 5, l = 2) and (n = 6, l = 0) energy states respectively to higher energy states. The absorption energies, i.e., conduction band energies of platinum nanoparticles derived from the absorption peaks increased with increasing dose and decreased with increasing particle size.
Keywords: nanoscience; metal nanoparticle theory; conduction electrons; conduction bands; platinum nanoparticles; radiolytic method; quantum mechanical calculation nanoscience; metal nanoparticle theory; conduction electrons; conduction bands; platinum nanoparticles; radiolytic method; quantum mechanical calculation
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Export to BibTeX |
EndNote


MDPI and ACS Style

Gharibshahi, E.; Saion, E. Influence of Dose on Particle Size and Optical Properties of Colloidal Platinum Nanoparticles. Int. J. Mol. Sci. 2012, 13, 14723-14741.

AMA Style

Gharibshahi E, Saion E. Influence of Dose on Particle Size and Optical Properties of Colloidal Platinum Nanoparticles. International Journal of Molecular Sciences. 2012; 13(11):14723-14741.

Chicago/Turabian Style

Gharibshahi, Elham; Saion, Elias. 2012. "Influence of Dose on Particle Size and Optical Properties of Colloidal Platinum Nanoparticles." Int. J. Mol. Sci. 13, no. 11: 14723-14741.


Int. J. Mol. Sci. EISSN 1422-0067 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert