ISSN 1070-4272, Russian Journal of Applied Chemistry, 2006, Vol. 79, No. 2, pp. 325!326. + Pleiades Publishing, Inc., 2006.
Original Russian Text + V. N. Tseluikin, I. S. Chubenko, I. F. Gun’kin, A. Yu. Pankst’yanov, 2006, published in Zhurnal Prikladnoi Khimii, 2006,
Vol. 79, No. 2, pp. 326!327.
Colloidal Dispersion of Fullerene C
Free of Organic Solvents
V. N. Tseluikin, I. S. Chubenko, I. F. Gun’kin, and A. Yu. Pankst’yanov
Engels Technological Institute, Saratov State Technical University, Engels, Saratov oblast, Russia
Received April 13, 2005
Abstract-A new procedure for preparing aqueous colloidal dispersion of C
in water was developed.
is insoluble in water, which compli-
cates its practical use. However, colloidal aqueous dis-
persions of fullerenes can be prepared. A large portion
of fullerenes in their solution is in the form of clus-
ters . Dispersions of C
are prepared by addition
of water to an organic solution of the fullerene, with
the subsequent treatment resulting in precipitation of
colloidal particles . In the process, the organic
solvent is not removed from the solution.
The aim of this study was to prepare colloidal dis-
persions of fullerene C
in water free of admixtures
of other solvents.
A water3acetone mixture (1 : 3) containing 53
20 mM of sodium dodecyl sulfate as a stabilizer was
prepared. To this mixture, a solution of fullerene C
in chlorobenzene (2.2 mg ml
) was added dropwise
with vigorous stirring on a magnetic stirrer. The re-
sulting yellow homogeneous solution was distilled
under atmospheric pressure with vigorous stirring.
The first evaporated fraction was acetone. The second
fraction was chlorobenzene3water azeotrope. In the
course of evaporation of the azeotrope, the fullerene
became dispersed in water. Finally, water [refractive
index n = 1.3330 (20oC)] was distilled off. Disper-
sions containing 0.05 to 0.50 g l
ared. Their color varied from yellowish to brown as
the fullerene concentration increased. The chloroben-
zene band with l
= 264 nm  is absent in the elec-
tronic absorption spectrum of the aqueous dispersion
. Hence, chlorobenzene was completely re-
moved from the dispersion. It should be noted that
the dispersions are highly stable: no coagulation is ob-
served in the course of at least a month. The average
particle size of aqueous dispersions of C
lated from the turbidity spectrum by the equation 
is the geometric mean wavelength of the
spectral range examined; m
, refractive index of the
dispersion medium; and a, coefficient dependent on
the parameter n (n = Dlog D/Dlog l).
The average size of the colloidal particles is 40 nm.
A yellow homogeneous solution (the initial C
solution in chlorobenzene is violet) is also formed
when a C
solution in chlorobenzene is added drop-
wise with vigorous stirring to a water3acetone mix-
ture (1 : 3) without a stabilizer. The D(l) spectrum
dramatically changes under these conditions, i.e.,
the solvatochromic effect is observed. The D(l) spec-
trum of a C
solution in chlorobenzene contains
bands in the ranges l = 3803410 and 5103570 nm.
In going to a chlorobenzene3water3acetone system,
the optical density significantly increases in the whole
wavelength range (Fig. 2).
The solvatochromic effect is due to aggregation of
fullerenes upon a change in the solvent composition
Fig. 1. Absorption spectrum of colloidal dispersion of
in water. (D) Optical density and (l) wave-
length. Fullerene concentration 3.5 0 10