A Supercapacitor (SC) is also called an Ultracapacitor.
Flexible supercapacitors are highly attractive for the large number of
emerging portable lightweight consumer devices.
The novelty of a flexible supercapacitor is the incorporation of flexible
electrode or substrate material to combine structural flexibility with the
inherently high power density of supercapacitors.
8. Conducting polymers (CPs) have been
considered as the most promising materials
for flexible supercapacitors.
Reverse doping-dedoping behaviour of CPs
has been used for various smart
They can be synthesized either by oxidative
polymerisation or by electrochemical
polymerisation into different forms.
11. As per Journal 1 : Polyaniline is
deposited using a spray
technique onto a flexible current
collector for pseudocapacitor
The polyaniline is characterised
using FTIR, SEM, and optical
12. Electronically conducting polymers such as polypyrrole, polyaniline,
polythiophene and PEDOT can store & release charges through redox
When oxidation occurs, ions from the electrolyte are transferred to
the polymer backbone & on reduction, they are released back into
Among the conducting polymers, polyaniline has attracted much
Aniline is added to HCl
&kept for 1h at room
in 20mL of distilled
water is then added to
the suspension under
The prepared mixture
is filtered & then
rinsed with distilled
PANI is simultaneously
dedoped by 25mL of
NaOH at 900 C for 5h.
PANI is doped with
acid (CSA) and then
16. Electrochemical measurements
are performed using two
electrodes measurements in an
performance is analyzed for
supercapacitor electrodes in a
two-electrode system via
cyclic voltammetry (CV) and
spectroscopy (EIS) using a
26. As per Journal 2 : Pseudocapacitors made from
conducting polymers, which store charge via rapid
reduction and oxidation reactions, are a particularly
This perspective explores conductivity and charge
storage mechanisms in conducting polymers and
describes how synthetic strategies can aﬀect these
Developed the chemical correlations that have been
shown to enhance the performance of pseudocapacitive
electrochemical capacitors fabricated from conducting
27. The current commercial electrochemical capacitor is the electric
double-layer capacitor (EDLC) which store charge electrostatically,
similar to a traditional electrolytic capacitor.
Pseudocapacitors store charge through reduction and oxidation events
leading to a high energy density relative to EDLCs.
The goal of this work is to elucidate accessible chemistries that
eﬀectively control pseudocapacitive behavior in conducting polymers
and therefore advance electrochemical energy storage technologies.
29. To have both high conductivity and electrochemical
capacitance, it must possess charge carriers, charge mobility,
facile kinetics, and readily available solvated counterions.
Electron insertion into the conduction band via n-
doping and/or removing an electron from the valence
band via p-doping increase charge carrier
CP + n Red → (C+)n CPn-+ n Red+
CP + n Ox → CPn+ (A-)n + n Ox-
30. When a polymer undergoes ionization, the equilibrium
geometry of the ionized state is lower than that of the
This lattice deformation causes the HOMO energy to shift up
and the LUMO energy to shift down, creating new energy
bands in the band gap that are delocalized over the polymer
The more a polymer chain is ionized (“doped”), the more
these islands overlap and delocalize over the entire material.
33. It is important to
voltage window of
the device, the
capacitance of each
minimize the RESR of
output is P =
stored in an
l capacitor is, U
= ½ CV2
34. Potential diagrams of fully charged and discharged states of (a) Type I, (b) Type II,
(c) Type III and (d) Type IV electrochemical capacitor.
are poised as a
way to increase
given an inert
electrode in an
will be split into
oxygen at roughly 1
V vs Ag/AgCl and
hydrogen at −0.3 V
36. PANi is often
versus the reference
or oxygen evolution
depending on the
at the material
The safe working
window for a
device is generally
limited to around
0.6 to 0.8 V for
High conductivity in a conducting polymer and low internal cell resistance
are paramount to fast kinetics.
Too high of a packing density adversely limits electrolyte accessibility and
Chain length has a tremendous impact on mobility.
Increasing the degree of crystallinity and chain alignment, and producing a
defect free, homogeneous long chain polymer results in superior
39. The crystal structures of doped and undoped PEDOT
illustrate the interrelation between chain alignment and
Control of pore structure is a promising area of research
for inducing high surface area and inducing facile
Another versatile area for improving kinetics is self-doping
via layer-by-layer assembly of alternating poly(o-
methoxyaniline) and poly(3-thiophene acetic acid) films.
for low cycling
a polymer to
42. Extended cyclability can also be imparted
by depositing a thin carbonaceous shell
onto the conducting polymer electrode.
This physical buffer suppresses structural
deformation during cycling and leads to
95% capacitance retention for PANi and
85% for PPy electrodes after 10 000 cycles.
Nanostructures enhance free volume, accessible surface area,
and redox chemistry by promoting ion sorption and desorption
at the electrode/electrolyte interface.
Well-ordered nanowires and nanotube array with uniform
structure, high porosity and large surface area improve
capacitance and enhance charge/discharge rates in
mesoporous electrodes due to rapid ion diffusion.
44. PPy nanowire arrays improve stability during
charging/discharging cycles and achieve up to 566 and 259 F/g
at 1.1 and 13.75 A/g, respectively.
Various sized interconnected porous networks also facilitate
ion accessibility into the matrix of the material.
Porosity is essential for solvent diffusion and has a large effect
45. Ion accessibility is maximized using a highly porous,
amphiphilic and pH responsive α-cyclodextrin polyacrylamide
Specific capacitances of the stretched (315 F/g), folded
(301F/g), and original states (304 F/g) are based on the dry
weight of active mass PANi and remain capacitive at a high
charging density of 8 A/g.
47. • Heating of an aqueous ferric chloride
droplet in the presence of monomer
vapors leads to polymerization.
• This process is concomitant with droplet
evaporation, reduction of ferric chloride
to ferrous chloride, and precipitation of
• These oxidant crystallites direct structure
and result in PEDOT nanofibers with a
conductivity of 130 S/cm.
48. SEM IMAGE OF EVPP-PEDOT; (inset) X - RAY
PHOTOELECTRON SPECTRUM OF EVPP-PEDOT
49. As per Journal 3 : Recent developments of
nanocomposites are overviewed.
Material design, synthesis and applications in
flexible supercapacitors are highlighted.
Current challenges and future perspective are
play a crucial role
Although SCs store
lower amount of
batteries, in most
cases, their energy
density is still much
higher than that of
SCs can be fully
much longer time
kinetics through a
55. The double layer capacitance of an EDLC can be
expressed as: C = εrε0 A/D
Capacitance of a pseudocapacitor : C = ΔQ/ΔV
In conducting polymers based pseudocapacitors, the
charge/discharge processes are associated with the
doping/de-doping processes of conducting polymers.
56. Two important future
electrode and asymmetric
capacitors were indicated
considered as an
material for EDLC.
These studies show that
there is a significant
between graphene and
57. Graphene (Gr), a two-dimensional monolayer of sp2-
bonded carbon atoms, exhibits a range of remarkable
CPs hold promising characteristics for electrochemical
energy storage, however, their low stability under
charge/discharge conditions has limited practical
Gr can affect the molecular conformation and orientation
of CP chains, leading to the positive synergistic effect on
58. The integration of CP
with Gr prevents self-
aggregation or re-
stacking of graphene
Other advantages such as high surface
area considerable structural diversity,
small size of particles and short
distance for ion transfer, structural
uniformity and controllable
59. MATERIAL DESIGN, SYNTHESIS
METHOD AND PERFORMANCE
Several crucial aspects have to be considered in
the development of Gr/CP nanocomposites;
i) Appropriate methods of synthesis
ii) Surface compatibility of CP with Gr
iii) Controlling thickness and morphology of
the CP film
iv) Surface properties of the nanocomposite
material (e.g. surface roughness,
69. POLYMER BASED CAPACITORS
As per Journal 4 : Two important future research
directions: polymer/carbon material/metal oxide
ternary composite electrode and asymmetric
capacitors were indicated and summarized.
Graphene is considered as an ideal candidate
material for electrochemical doublelayer
70. ASSYMMETRIC CAPACITOR
There are limited studies on the measurement of
complete cells constructed with conductive polymer as
the electrode and most of these studies focus on the
There are limited studies on the measurement of
complete cells constructed with conductive polymer as
Combined with the advantages of long period, fast
reversible ac negative electrode and high conductivity
ionic water electrolyte of large capacity Faraday
72. CONDUCTIVE POLYMERS SUPERCAPACITOR
Type I : Completely identical p type doped conductive polymer.
Type II : Different kinds of p type doped conductive polymer.
Type III :One conductive polymer doped with n type and other
doped with p type.
75. Perspectives of the further development of Gr/CP
nanomaterials for the capacitive energy storage
purposes сan be related to two main directions.
The first one is concerned with the improvement of
intrinsic properties of Gr/CP nanomaterials.
Related to a variety of ways using complete Gr/CP-based
electrodes in SCs.
76. More recently, some cost-effective and template-free
methods for the scale-up or mass fabrication of 3D Gr
frameworks under mild conditions have been proposed.
A number of composites, fabricated by further
modification of the structures with CPs, have shown
These latest advances may open new ways to use Gr/CP
nanostructured composite materials for the
development of inexpensive and scalable capacitive
77. A lot of research
work has been
done to improve
the energy density
their high power
Considering that conductive
polymers can only be
reversible at a very small
potential range, their best
such as types on different
select of conductive
voltage of the
energy and power
• Preparation and characterization of a pseudocapacitor electrode by
spraying a conducting polymer onto a flexible substrate - Shaker
A.Ebrahim, Mohamed E.Harb, Moataz M.Soliman Mazhar B.Tayel.
• Conducting Polymers for Pseudocapacitive Energy Storage - Aimee M.
Bryan, Luciano M. Santino, Yang Lu, Shinjita Acharya and Julio M.
• Graphene-Conducting Polymer Nanocomposites for Enhancing
Electrochemical Capacitive Energy Storage - Fei Shen, Dmitry
Pankratov, and Qijin Chi.
• Conducting Polymers in Supercapacitor Application - D Y Su, Z G Liu, L
Jiang, J Hao, Z J Zhang and, J Ma.