ISSN 1070-4272, Russian Journal of Applied Chemistry, 2014, Vol. 87, No. 9, pp. 1251−1253. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © V.N. Tseluikin, A.A. Koreshkova, 2014, published in Zhurnal Prikladnoi Khimii, 2014, Vol. 87, No. 9, pp. 1255−1258.
INORGANIC SYNTHESIS AND INDUSTRIAL
Deposition of Zinc–Carbon Nanotube Composite
Coatings in the Pulse-Reverse Mode
V. N. Tseluikin and A. A. Koreshkova
Engels Technological Institute, Branch of Yuri Gagarin State Technical University of Saratov,
pl. Svobody 17, Engels, 413100 Russia
Abstract—Composite electrochemical zinc–carbon nanotube coatings were deposited in the pulse-reverse mode.
The structure and service properties of these coatings were studied. It was found that introduction of carbon
nanotubes into a zinc plating electrolyte reduces the friction coefﬁ cient and improves the corrosion resistance of
the coatings being formed.
One of ways to modify machinery parts is by
deposition of composite electrochemical coatings (CECs)
onto their surface. The fabrication principle of CECs is
based on joint deposition of metals and dispersed particles
from suspension-electrolytes [1–3]. CECs base on zinc
are used for protecting steel articles from corrosion
and improving their physicomechanical properties .
According to the data reported in , about half the
world’s production of zinc is intended for fabrication of
electrochemical coatings. The service parameters of CECs
are largely determined by the nature of the dispersed
phase. At present, composite coatings modiﬁ ed with
nanosize particles of varied nature are being actively
studied. This tendency is due to the improvement of the
functional properties of CECs upon inclusion of various
nanoparticles into the metallic matrix .
Carbon nanotubes (CNTs) belong to promising
nanomaterials. These are cylindrical molecules formed
upon rolling-up of planar atomic layers of graphite
(graphenes). CNTs may be single- or multi-walled (be
constituted by several coaxial cylinders). The inner
diameter of the nanotubes is in the range from 0.4 nm to
several nanometers, and their length does not exceed, as
a rule, tens of micrometers [6, 7].
The goal of our study was to obtain zinc–CNT
composited coatings in the reverse mode and to analyze
their tribological and corrosion properties. The advantage
of reverse electrolysis mode is in the substantially larger
number of parameters controlling the coating deposition
process. Unsteady modes favor formation of coatings with
a high content of nanoparticles and their homogeneous
distribution within the deposit.
Zinc-based composite electrochemical coatings
were deposited from the electrolyte of the following
composition (g L
O 120, NH
polyethylene polyamine 5, carbon nanotubes 0.05. The
coatings were deposited onto a steel base (St, 45) at room
temperature under permanent agitation of the solution.
Purely zinc coatings were produced from an electrolyte
of the same composition without the dispersed phase.
The adhesion of the resulting coatings was assessed by
deposition of a grid of scratches [GOST (State Standard)
We examined the electrodeposition of zinc coatings in
the pulse-reverse mode at current densities i
= 6 A dm
= 1.5 A dm
. The ratio between the cathodic and
anodic periods were 10 : 1, 12 : 1, 14 : 1, and 16 : 1 (s/s).
Electrochemical measurements were made with a
P-30S pulse potentiostat. The potentials were set relative
to the saturated silver chloride reference electrode and
were recalculated to the hydrogen scale.