ISSN 1070-4272, Russian Journal of Applied Chemistry, 2014, Vol. 87, No. 4, pp. 491−495. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © P.V. Vlasov, M.A. Smirnov, I.Yu. Dmitriev, N.N. Saprykina, G.K. Elyashevich, 2014, published in Zhurnal Prikladnoi Khimii, 2014, Vol. 87,
No. 4, pp. 499−504.
AND POLYMERIC MATERIALS
Electrochemical Activity and Structure of New Composite
Systems Based on Cross-Linked Polyacrylamide
P. V. Vlasov, M. A. Smirnov, I. Yu. Dmitriev,
N. N. Saprykina, and G. K. Elyashevich
Institute of Macromolecular Compounds, Russian Academy of Sciences, Bolshoy pr. 31 St. Petersburg, 199004 Russia
Received April 4, 2014
Abstract—A procedure was developed for preparing electroactive composite systems based on polyacrylamide
hydrogel and a conducting polymer, polyaniline. The overall electrical conductivity of the composite systems was
measured by chronoamperometry, and the contributions of the electronic and ionic constituents were calculated.
The speciﬁ c capacity of the composites was calculated using galvanostatic charge–discharge cycles, and the
stability of the capacity at cycling was evaluated.
In the recent years, the researchers’ attention has been
focused on various electrochemical systems suitable for
energy production and storage. Electrochemical capaci-
tors known also as ionistors or supercapacitors occupy a
special place among these systems. The speciﬁ c energy
accumulated by a supercapacitor is considerably higher
than the energy that a common capacitor is capable to
accumulate. This is associated with extremely small thick-
ness of the electrical double layer (acting in this case as
capacitor plates) in supercapacitors and with considerably
higher speciﬁ c surface area. Two mechanisms of en-
ergy accumulation by supercapacitors are distinguished:
(1) due to capacity of the electrical double layer and (2)
due to reversible redox electrochemical processes (Fara-
day processes). Supercapacitors based on carbon mate-
rials of comparatively high electrical conductivity and
high speciﬁ c surface area operate by the ﬁ rst mechanism.
Pseudocapacitors in which the capacity arises owing to
electrosorption or redox reactions involving the electrode
material belong to the second type of energy accumula-
tors. Actually the operation principle of supercapacitors
of the second type combines both mechanisms of energy
storage, namely, electrostatic interaction as in capacitors
with electrical double layer and Faraday reactions analo-
gous to the processes on which the operation of cells and
batteries is based.
Devices in which conducting polymers are used as
electrodes are a promising kind of supercapacitors .
Electrodes of such type belong to a new class of elec-
troactive materials generally termed bulk electrodes.
Polyelectrolytic hydrogels play the role of matrix for the
electrode constituent in such devices . Hydrogels are
ionic conductors, and they can ensure the accumulation
of the electric ﬁ eld energy owing to the formation of the
electrical double layer, whereas the conducting polymer
exhibiting the electronic conductivity and capability for
redox reactions can impart pseudocapacity to the system.
A distinctive feature of such devices is high speciﬁ c area
of the interface between the ionic and electronic con-
ductors. As a result, the whole volume of the electrode
becomes involved in the energy accumulation by both
mechanisms, which allows the energy storage density to
be considerably increased.
The traditional method for preparing composite sys-
tems conducting polymer–hydrogel [3–6] consists in that
the cross-linked matrix hydrogel is synthesized ﬁ rst, and
then it is brought to the state of equilibrium swelling in a
solution of the monomer of the conducting component.
The resulting system is placed in a solution of the mono-
mer polymerization initiator, and the conducting polymer
is thus synthesized. This procedure has signiﬁ cant draw-
backs associated with the fact that, because of limited dif-