1070-4272/04/7712-1935 C 2004 MAIK [Nauka/Interperiodica]
Russian Journal of Applied Chemistry, Vol. 77, No. 12, 2004, pp. 1935!1938. Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 12, 2004,
Original Russian Text Copyright + 2004 by Eremenko, Besedina, Obraztsova.
AND ION-EXCHANGE PROCESSES
Surface Chemistry of Ultradispersed Diamonds
A. N. Eremenko, O. A. Besedina, and I. I. Obraztsova
Kemerovo Branch of the Institute of Solid-State Chemistry and Mechanochemistry, Siberian Division,
Russian Academy of Sciences, Kemerovo, Russia
Received August 18, 2004
Abstract-The type and amount of functional groups on the surface of ultradispersed diamonds were
determined. The adsorption of potential-determining ions was studied in relation to various factors, and
the surface charge density was evaluated. The influence exerted by thermal treatment in argon and hydrogen
on the functional composition of the surface was analyzed.
A new research area, [nano: -particles, -materials,
and -technologies,] has formed and has been generally
accepted as a priority field of world’s science.
By the term [nanotechnology] is understood crea-
tion and use of materials, devices, and systems
whose structure is controlled on the nanometer scale.
The primary goal is to reveal the principles governing
the physicochemical properties of such materials and
methods for their fabrication and to thereby master
the prognostication of, and control over the properties
of the objects obtained.
The specificity of the properties of the substances
in question and the associated new physical phenom-
ena are determined by the fact that the characteristic
dimensions of the structural elements of nanoobjects
are within the range 10
m, which is compa-
rable with the size of atoms and molecules in ordinary
materials. Novel functional characteristics, markedly
differing from those of ordinary materials, can be
imparted to nanomaterials by controlling the dimen-
sions and shape of nanostructures.
In the authors’ opinion, ultradispersed diamonds
(UDD) are the most interesting objects of study among
all kinds of nanomaterials: they possess a unique
combination of markedly anomalous chemical, phys-
icochemical, and mechanical properties.
Ordinary (natural) diamonds are, as a rule, used
only as abrasive and cutting materials or substrates in
microelectronics. At the same time, the application
field of UDD is rather wide. By chemical, barometric,
or thermal treatment, various surface properties can
be imparted to UDD. In this context, the attention of
researchers is focused on a detailed study of param-
eters and properties of diamonds and on a search for
new areas of their application. It is believed that
the main application fields of UDD have not been
found yet, and their wide use in future high-tech pro-
jects is expected .
Many physicochemical properties of diamonds
strongly depend on the composition and properties of
their surface, which is formed in synthesis and chem-
ical treatment of the material. In a number of cases,
this is the key issue in obtaining new diamond-con-
taining composites with prescribed characteristics.
The electrokinetic, ion-exchange, and sorption prop-
erties of diamonds are primarily determined by the na-
ture and amount of surface functional groups. De-
spite the existence of numerous methods for studying
the surface of detonation-produced diamonds (spec-
tral, thermographic, potentiometric, polarographic),
the available information about its chemical composi-
tion is of mostly qualitative nature .
In view of the importance of the surface chemistry
of UDD for various applications, some quantitative
characteristics of the chemical composition of the
UDD surface were determined in the present study.
UDD with particle size of 335 nm were used;
the method for their recovery from the detonation-
produced diamond-carbon stock and subsequent pur-
ification has been developed previously [2, 3].
The type and amount of acid groups were found by
reverse acid3base titration by selective neutraliza-
tion with sodium hydroxide, hydrocarbonate, and car-
bonate by the Boem method  developed for carbon