Russian Journal of Applied Chemistry, 2009, Vol. 82, No. 4, pp. 592−595.
Pleiades Publishing, Ltd., 2009.
Original Russian Text
O.N. Shcherbinina, N.G. Medvedeva, S.S. Popova, E.L. Surmenko, 2009, published in Zhurnal Prikladnoi Khimii, 2009, Vol. 82,
No. 4, pp. 599−602.
AND CORROSION PROTECTION OF METALS
Electrochemical Modiﬁ cation of Copper-Based Matrix
Structures with Calcium
O. N. Shcherbinina, N. G. Medvedeva, S. S. Popova, and E. L. Surmenko
Engels Technological Institute, Branch of Saratov State Technical University, Engels, Saratov oblast, Russia
Received June 18, 2008
Abstract—Electrochemical behavior of a copper electrode in solutions of calcium chloride in dimethylformamide
was studied in the concentration range 0.027−0.63 M at various electrode potentials. The diffusion-kinetic
characteristics of the CaCu alloy formed on the copper surface under the conditions studied were calculated.
Recently, a new field of chemistry, chemistry of
intercalated compounds and, in particular, cuprates in the
system BiPCaCuO, has been rapidly developing [1, 2].
The interest in these compounds is due to broad prospects
for their use as new superconductors, hyperanisotropic
materials, and materials for new generations of reversible
chemical power sources. Synthesis of superconducting
cuprates with exceedingly high transition temperatures
(225 K and higher), development of algorithms to be used
in a search for compounds with a high temperature of
transition into the HTS state, and design of new methods
for synthesis of HTS materials are the most important
areas of basic research in chemistry and technology
of high-temperature superconductors [1−4]. Rather
promising as regards controlled synthesis of metallic
composites with the HTS stoichiometry, distinguished
by homogeneous distribution of components, is the
electrochemical method of cathodic incorporation .
This method is used to obtain composite structures
differing in oxidizing properties from metallic alloys.
Studies devoted to this subject are few in number.
Thus, development of theoretical foundations of new
electrochemical techniques for deposition of complex-
composition ﬁ lms possessing the structure and properties
of HTS is a topical ﬁ eld of electrochemical technology.
Treatment of surface metal layers by the method of
electrochemical incorporation at room temperature can
change the nature of the metal surface by imparting a
number of speciﬁ c physical properties and provide a high
degree of purity of a product .
The experiment was performed on a setup including
a P-5848 potentiostat and a KSP-4 self-recorder or
oscilloscope. The cathodic treatment of samples was
made in the potentiostatic mode at potentials of –2.2
to –3.0 V in solutions of calcium chloride CaCl
dimethylformamide (DMF), with concentrations of
0.027, 0.09, 0.36, and 0.63 M. The polarization time at
each prescribed potential was 45 min, and a nonaqueous
silver chloride electrode (s.c.e.) served as reference.
A high-purity (99.99%) copper plate with a working
surface area of 1.5 cm
was used as the working electrode.
Fig. 1. Potentiostatic curves for cathodic incorporation of
calcium into copper from a 0.63 M solution of CaCl
at various potentials. (i) Current density and (t) time; the same
for Figs. 3–5. E (V): (1) –2.2, (2) –2.4, (3) –2.6, (4) –2.8, and
(5) –3.0; the same for Figs. 2–4.
i, mA cm