Photochemical and Photophysical Properties of Sequentially Functionalized Fullerenes in the Aqueous Phase

Title
Photochemical and Photophysical Properties of Sequentially Functionalized Fullerenes in the Aqueous Phase
Authors
Samuel D. Snow이재상Jae-Hong Kim
Issue Date
2012-12
Publisher
Environmental science & technology
Citation
VOL 46, NO 24, 13227-13234
Abstract
The vast range of C60 derivatives makes it difficult to assess the potential environmental impact of this class of materials, while past environmental studies mostly focused only on pristine C60. Central to derivatized C60’s potential to negatively impact (micro)biological receptors upon unintended release is its unique property of mediating the transfer of light energy to ambient oxygen, producing 1O2. To initiate the process of establishing a thorough understanding of the photoinduced adverse biological effects of functionalized fullerenes and their aqueous dispersions, the photochemical properties relevant to 1O2 production were evaluated using three selected series of mono-, bis-, and tris-adducted fullerene materials. Differential 1O2 production of derivatives in toluene were explained by spectral variations under visible and UVA light conditions. Of the nine functionalities studied only aggregates of two positively charged derivatives showed significant photoactivity under experimental conditions. Laser flash photolysis revealed a triplet excited state in the photoactive aggregates with a sufficiently long lifetime to be quenched by 3O2. Dynamic light scattering, transmission electron microscopy, and electron diffraction patterns revealed aggregates with sizes typical of aqueous C60 colloids that varied in crystallinity based on functionality. Results raised questions about our current understanding of the photoactivity of fullerene aggregates.
URI
http://pubs.kist.re.kr/handle/201004/44378
ISSN
0013936X
Appears in Collections:
KIST Publication > Article
Files in This Item:
There are no files associated with this item.
Export
RIS (EndNote)
XLS (Excel)
XML


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE