FIELD OF INVENTION
[001] The present invention relates to an energy storage device, more particularly to a supercapacitor or electrochemical capacitor utilizing electrode material comprising Anionic surfactant assisted Conducting Polymer-Carbon Allotropes Composites as high performance Supercapacitor Electrodes. The present invention, being an improvement in or modification of another invention from the same applicant Uttaranchal University, filed on March 13, 2018, with the patent application number 201811009209, titled “Supercapacitor comprising of surfactant doped conducting polymer-carbon substrates composites” is filed as a patent of addition.
[002] Definitions of Terms and Phrases

CP: Conducting Polymers
PPy: Polypyrrole
SLS: Sodium Lauryl Sulfate
SLSD: Sodium Lauryl Sulfate Doped
NaDBS: Sodium Dodecyl Benzene Sulphonate
CNT: Carbon Nanotube
GR: Graphene
HCA/ HC: Hybrid Carbon Assemblage/ Hybrid Carbon

[003] It may be noted that as per the requirement of invention disclosure, terms or phrases are used in several combination.

BACKGROUND AND PRIOR ARTS OF INVENTION

[004] Supercapacitor has emerged as new technology in energy storage. Supercapacitor stores electrostatic energy. As voltage is applied across system unlike charges attract each other. Ions in electrolyte diffuse across separator into the pores of electrodes, but electrodes are so designed that they prevent recombination of ions. These double layers coupled with an increase in area and decrease in distance between electrodes and achieve high energy density than conventional capacitor, as during whole process there is no transfer of electrical charge or chemical change, these charges are associated with non-faradic process. As the process is non faradic super capacitor possess properties such as large number of charging and discharging cycles, highly reversible stored charge. Super capacitor can have aqueous or organic electrolyte. Aqueous electrolyte includes H2SO4 and KOH. Among conducting polymers, Polypyrrole (PPy) has been widely investigated as promising candidate because of its better conductivity and large specific capacitance. The use of PPy is particularly promising because of its high energy storage capacity, good electrical conductivity, ease of synthesis in aqueous solution, and stability in ambient air. However, PPy is not soluble in organic solvents and water because of the strong intermolecular and intramolecular interactions and crosslinkings of PPy chains. Therefore, to overcome the insolubility problem of PPy, many researchers have studied soluble PPy. The dopant reduces the intermolecular and intramolecular interactions of PPy chains and improves the solubility of PPy in an organic solvent. Incorporation of anionic surfactants caused enhanced electrical conductivity, increased yield, decreased the size of particles as well as improved the thermal stability of the resultant PPy. The presence of anionic surfactant seems to inhibit undesirable side reactions so as to improve the regularity of the PPy backbone.

[005] Furthermore, the main drawback of CPs application as supercapacitor electrodes is connected with their poor stability during cycling. The CP films, due to volumetric changes during the doping/dedoping process (insertion/deinsertion of counter ions), undergo swelling, shrinkage, cracks or breaking that in consequence gradually aggravates their conducting properties. Additionally, the electrochemical activity of each CP is strictly determined by its working potential range limited by an isolating state and/or polymer degradation caused by over oxidation. Our target is to overcome this stability problem of CPs with cycling by using their composites with carbon nanotubes (CNTs), graphene and hybrid carbon assemblage as mesoporous conducting network able to adapt to all the mechanical stress. Recently, the preparation of conducting polymer and carbon allotropes composites have attracted considerable interest not only the CNTs and graphene can improve the mechanical and electrical properties of composites but also the composites possess the properties of individual component with a synergistic effect. These composites were shown to enhance charge density, electrical conductivity, and electrochemical activity compared with pure conducting polymer materials. Thus, the purpose of this study is to examine the effect of wrapping of PPy over three different carbon allotropes i.e. amine functionalized multiwalled CNTs (AMWCNTs), graphene and hybrid carbon assemblage and also investigate the effect of doping agent sodium dodecyl benzene sulphonate (NaDBS) on the morphology and pseudocapacitive behavior of the PPy synthesized by chemical oxidation.

[006] US 20160012978 provides a supercapacitor or electrochemical capacitor with reduced ionic impedance of the electrodes which greatly increases the frequency of operation as compared with the previously known supercapacitors. This means that supercapacitors according to embodiments of the present invention enjoy faster discharge and charging time compared with other previously known supercapacitors. In brief, the supercapacitor comprises spaced apart electrodes which are separated from each other by a separator. The separator is made of an electrical insulating material, such as a porous polymer. Each of the electrodes is formed of carbonaceous material and capable of being impregnated with a liquid electrolyte. Metal current collectors are provided on the sides of the electrodes opposite from the separator. The electrical energy storage is achieved by charge separation at the electrode carbonaceous material surfaces. Unlike the previously known supercapacitors, according to embodiments of the present invention, holes are formed through the electrodes. The holes extend generally from the metal current collector and towards the separator, and may be aligned, preferably in a grid pattern. These holes within the electrodes facilitate the rapid travel of electrolyte ions through the electrode thickness. Thus, since the electrolyte ions travel throughout the electrodes during charging and discharging, more rapid charging and discharging of the supercapacitor is achieved.

[007] US 7061749 relates to a supercapacitor device having an electrode material prepared from single-Wall carbon nanotubes and polymer, and method for making the same. In present invention, supercapacitor comprises with two electrodes, at least two current collectors, and an electrolyte in contact with and interposed between the electrodes. The electrodes comprise an activated carbonaceous polymer-nanotube material comprising single-Wall carbon nanotubes and polymer, wherein the polymer-nanotube material was pyrolyzed and activated. The current collectors comprise a conducting material and are each in contact with electrode. The supercapacitor of the present invention includes electrodes comprising single-Wall carbon nanotubes and polymer that has been carbonized, wherein the electrodes are in contact with an electrolyte between the electrodes, wherein the electrodes are in contact with and interposed between two conducting current collectors. If the electrolyte is a fluid or compressible medium, a non-conducting separator, permeable to the electrolyte ions, is interposed between the electrodes to prevent shorting.

[008] US 2012/0026643 demonstrates fabrication of supercapacitor comprising a two electrodes, a porous separator disposed between the two electrodes, and an ionic liquid electrolyte in physical contact with the two electrodes, Wherein at least one of the two electrodes comprises a mesoporous structure being formed of a plurality of nano graphene platelets and multiple pores having a pore size in the range of 2 nm and 25 nm and the graphene platelets are not spacer-modified or surface-modified platelets. Preferably, the graphene platelets are curved, not flat-shaped. The pores are accessible to ionic liquid molecules, enabling the formation of large amounts of electric double layer charges in a super capacitor, which exhibits an exceptionally high specific capacitance and high energy density.

OBJECTS OF THE INVENTION

[009] The principal object of the present invention is to provide a super capacitor device comprising Anionic surfactant assisted Conducting Polymer-Carbon Allotropes Composites as high performance Supercapacitor Electrodes.

[0010] Another object of the present invention is to provide a process for preparation of the anionic surfactant assisted conducting polymer composite as high performance electrode material.
SUMMARY OF THE INVENTION
[0011] The present invention, being an improvement in or modification of another invention from the same applicant Uttaranchal University, filed on March 13, 2018, with the patent application number 201811009209, titled “Supercapacitor comprising of surfactant doped conducting polymer-carbon substrates composites” is filed as a patent of addition.

[0012] The present invention discloses and claims a process for preparing polypyrrole and sodium dodecyl benzene sulphonate doped polymer carbon substrate composite as supercapacitor electrode, said process comprising the steps of injecting 0.025M of pyrrole into a suspension of 0.05 – 0.5g, preferably 0.1 g of carbon substrates selected from carbon nanotubes (CNT) or graphene (GR) or hybrid carbon assemblage (HC), preferably HC in 10 – 40 %, preferably 20% methanol solution; adding with an equivalent 0.005 – 0.02 M, preferably 0.01 M anionic surfactant Sodium dodecyl benzene sulfonate (NaDBS) and 0.005- 0.01 M FeCl3 solution and allowed to proceed at 0–5 ºC for 24 hours; filtering and washing subsequently. The pyrrole and NaDBS solution was ultrasonicated for 40 ~ 60 min prior to cooling in an ice bath for uniform dispersion. 0.49 g FeCl3 in 1 M HCl solution is prepared and allowed to proceed at 0–5ºC for 24 h followed by filtration, washing subsequently with ethanol and water, and drying overnight at 60ºC in vacuum.
BRIEF DESCRIPTION OF THE ACCOMPANYING FIGURES
Fig. 1: FTIR spectras of (a) PPy (b) PPy-CNT (c) PPy-GR and (d) PPy-HC
Fig. 2: FTIR spectras of (a) DPPy (b) DPPy-CNT (c) DPPy-GR and (d) DPPy-HC
Fig. 3: XRD graph of (a) PPy (b) PPy-CNT (c) PPy-GR and (d) PPy-HC
Fig. 4: XRD graph of (a) DPPy (b) DPPy-CNT (c) DPPy-GR and (d) DPPy-HC
Fig. 5: SEM images of (a) PPy (b) PPy-CNT (c) PPy-GR and (d) PPy-HC
Fig. 6: SEM images of (a) DPPy (b) DPPy-CNT (c) DPPy-GR and (d) DPPy-HC
Fig. 7: CV studies at different scan rates of (a) PPy (b) PPy-C (c) PPy-G and (d) PPy-HC
Fig. 8: CV studies at different scan rates of (a) DPPy (b) DPPy-CNT (c) DPPy-GR and (d) DPPy-HC
Fig. 9: Galvanostatic Charge Discharge studies at different current densities of (a) PPy (b) PPy-CNT (c) PPy-GR and (d) PPy-HC
Fig. 10: Galvanostatic Charge Discharge studies at different current densities of (a) DPPy (b) DPPy-CNT (c) DPPy-GR and (d) DPPy-HC
Fig. 11: EIS spectra of (a) undoped PPy electrodes and (b) NaDBS doped PPy
Fig. 12: Ragone plot of electrodes for (a) undoped PPy and (b) NaDBS doped PPy

DETAILED DESCRIPTION OF THE INVENTION
[0013] At the very outset of the detailed description, it may be understood that the ensuing description only illustrates a particular form of this invention. However, such a particular form is only exemplary embodiment, and without intending to imply any limitation on the scope of this invention. Accordingly, the description is to be understood as an exemplary embodiment and teaching of invention and not intended to be taken restrictively.
[0014] Throughout the description and claims of this specification, the phrases “comprise” and “contain” and variations of them mean “including but not limited to”, and are not intended to exclude other moieties, additives, components, integers or steps. Thus, the singular encompasses the plural unless the context otherwise requires. Wherever there is an indefinite article used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

[0015] Features, integers, characteristics, compounds, chemical moieties or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. The invention is not restricted to the details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification including any accompanying claims, abstract and drawings or any parts thereof, or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

[0016] The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference. Post filing patents, original peer reviewed research paper shall be published.

[0017] The present invention relates to a fabricate Supercapacitor device comprising doping agent anionic surfactant sodium dodecyl benzene sulphonate (NaDBS) assisted Conducting Polymer-Carbon allotropes Composites as high performance electrode material. The anionic surfactant sodium dodecyl benzene sulphonate (NaDBS) doped polypyrrole-amine functionalized carbon nanotube (AMWCNTs), graphene and hybrid carbon assemblage (AMWCNTs+graphene) composites were prepared via interfacial chemical oxidative polymerization of pyrrole deposited onto the carbon nanotubes, graphene and hybrid carbon assemblage.

[0018] The capacitance value of each sample was calculated from cyclic voltammograms by the following relationship:
[0019] Capacitance =Average Current/Scan Rate
[0020] The specific capacitance value for each sample was calculated by the following relation:-
[0021] Sp. Capacitance=Capacitance/Weight of Electrode

[0022] The specific capacitance of Polypyrrole and PPy-CNT, PPy-GR, PPy-HC composites as per calculation from figure were 107F/g, 173F/g, 267F/g, 356F/g at 5mV/sec respectively. The calculated specific capacitances for DPPy, DPPy-CNT, DPPy-GR, DPPy-HC by above equation were 193F/g, 232F/g, 317F/g and 473F/g at 5mV/sec respectively. The difference in the current between pure polymer and the composites obtained from CV curves can be explained by that the composite has a significantly more porous structure for ion transport, and higher and potential independent electronic conductivity through the embedded functionalized MWCNTs, graphene and combined graphene-AMWCNTs. The specific capacitance values can be obtained by the galvanostatic discharge curves according to the equation:

[0023] Cs =C/m= I?t/m?V
[0024] where I is the current of discharge, ?t is the discharge time, m is mass of the coated material, ?V is the potential range in the discharge, and Cs is the specific capacitance of the material. In this study, current density (I/m) of 1A/g to 2A/g was employed for the charge–discharge cycles. The specific capacitance values of PPy, PPy-CNT, PPy-GR and PPy-HC with Eq. (1) were 87, 168, 202 and 252 F/g at 1A/g respectively. The values of specific capacitance could be enhanced from 87 to 252 F/g. The calculated specific capacitances for DPPy, DPPy-CNT, DPPy-GR and DPPy-HC from Eq (1) were 217, 278, 403 and 587F/g at 1A/g respectively. For all eight electrodes, the current densities increased with increase in scan rate, indicating their good rate capability. On comparison this is concluded that anionic doping enhance the pseudocapacitive behaviour of PPy. This enhanced pseudocapacitive behaviour may be attributed to the inhibition of self-agglomeration of coated PPy polymer over the carbon substrate. The self agglomeration in undoped PPy samples hinder the diffusion of the electrolyte into the electrode, an as a result, some of the PPy chains might not participate in the redox reactions.

[0025] In the present subject matter, supercapacitor comprising at least two electrodes of conducting polymer i.e Polypyrrole Conducting Polymer-Carbon Substrates Composites and activated charcoal (AC) material has been disclosed.

[0026] In the present subject matter, the monomer chosen for study is pyrrole.

[0027] In another embodiment of the present subject matter, the oxidant chosen for above study was Ferric Chloride (FeCl3).

[0028] In another embodiment of the present subject matter, AMWCNTs, GR and HC assemblage (AMWCNTs + GR) act as substrates for deposition of conducting polymer.

[0029] In another embodiment of the present subject matter, the solvent of interfacial polymerization chosen is deionized water.

[0030] In another embodiment of the present subject matter, the temperature of the polymerization condition was kept between 0-5°C.

[0031] In another embodiment of the present subject matter, SLS was used as surfactant and dopant.

[0032] In another embodiment of the present subject matter, the polymerization reaction time was kept between 6-8 hours.

[0033] In another embodiment of the present subject matter, the prepared composites were washed by deionized water and dried at 50 °C.

[0034] In another embodiment of the present subject matter, Electrochemical workstation Metrohm AUT86472 (Netherland) was employed for the electrochemical measurement of the samples at ambient temperature. The electrochemical performances were evaluated by cyclic voltammetry (CV), galvanostatic charge–discharge (GV) and electrochemical impedance spectrum (EIS) in a conventional three-electrode electrolytic cell with a platinum wire, a silver/ silver chloride (Ag/ AgCl) and the composite electrode as the counter electrode (CE), reference electrode (RE) and working electrode (WE), respectively.

[0035] In another embodiment of the present subject matter, the working electrodes were prepared by mixing the synthesized electrode materials, activated charcoal, and poly (vinyldieneflouride) (PVDF) with a mass ratio of 70:20:10.

[0036] In another embodiment of the present subject matter, a small amount of N,N dimethylformamide was added to obtain a homogenous slurry, which was subsequently painted on a graphite sheet (1×1 cm2) by brush and allowed to dry at 65ºC in vacuum for 24 h for 3-Electrode Cell study.
[0037] In another embodiment of the present subject matter, the electrolyte was 6M KOH aqueous solution. CVs were carried out at the scan rates ran-ging from 5 to 100 mVs-1 within the potential range of -0.3 V to 1 V (vs. Ag/ AgCl). Galvanostatic charge–discharge test was recorded at current densities ranging from 0.5 Ag-1 to 2 Ag-1 with the same potential range. EIS measurements were performed around open circuit potential in the frequency range of 105–10-2 Hz with ac amplitude of 5 mV.

[0038] In another embodiment of the present subject matter, in the two-electrode system, two electrodes with the same weight and size were used as the test electrode and counter electrode and were separated by a polypropylene membrane.

[0039] The present invention thus discloses a supercapacitor comprising at least two electrodes comprising conducting polymer i.e. Polypyrrole and anionic surfactant NaDBS doped Polypyrrole conducting Polymer-Carbon Allotropes amine functionalized multiwalled carbon nanotubes (AMWCNTs), Graphene and Hybrid carbon assemblage composites and activated charcoal (AC) material at least two current collectors comprising of graphite sheets, each in contact with an electrode comprising of conducting polymer i.e. Polypyrrole and anionic surfactant NaDBS doped Polypyrrole conducting Polymer-Carbon allotropes composites and activated charcoal (AC) material, wherein the current collector comprises a conducting material; and an electrolyte comprising an aqueous solution of a compound selected from the group consisting of sulphuric acid, potassium hydroxide, and sodium hydroxide interposed between the electrodes. The supercapacitor further comprises a non-conducting separator in between the at least two electrodes wherein the separator is permeable by the electrolyte, and said separator comprises a material selected i.e. polypropylene membrane. The electrolyte was 6M KOH aqueous solution. CVs were carried out at the scan rates ranging from 5 to 100 mVs-1 within the potential range of -1 V to 1 V (vs. Ag/ AgCl) for unoped samples and -0.35V to 0.65V for NaDBS doped electrode materials. Galvanostatic charge–discharge test was recorded at current densities ranging from 1Ag-1 to 2 Ag-1with the same potential range. EIS measurements were performed around open circuit potential in the frequency range of 105–10-2 Hz with ac amplitude of 5 mV.

[0040] The working electrodes were prepared by mixing the synthesized electrode materials, activated charcoal, and poly (vinyldieneflouride) (PVDF) with a mass ratio of 70:20:10, wherein a small amount of N,N dimethylformamide was added to obtain a homogenous slurry of electrode materials, which was subsequently painted on a graphite sheet (3×3 cm2) by brush and allowed to dry at 65?C in vacuum for 24 h.

[0041] The energy density and power density of samples approached from 48 to 326 Wh/kg and 659 to 1262 W/kg, respectively, at a current density of 1 A/g. From the Ragon plot, it is observed that the DPPy-HC composite exhibit the highest energy density as well as maximum power density compared to other samples. The maximum power density of 3853 W/kg is obtained for DPPy-HC composite at 2 A/g. These results indicate that large power range could be obtained while maintaining high energy density and these electrodes can be utilized for high power applications. To sum up conductive polymer (PPy) onto high-surface area carbon materials has been introduced in order to create composite electrodes that combine the advantages of both materials. The doping inhibit the self agglomeration of PPy due to strong intermolecular and intramolecular interactions and crosslinkings of PPy chains and leads to enhanced specific capacitance.

[0042] Thus, in general a supercapacitor comprising at least two electrodes comprising Polypyrrole Conducting Polymer-Carbon Substrates Composites and activated charcoal material, at least two current collectors comprising of graphite sheets, each in contact with an electrode, wherein the current collector comprises a conducting material; and an electrolyte interposed between the electrodes.

[0043] The supercapacitor may further comprising a non-conducting separator in between the at least two electrodes wherein the separator is permeable by the electrolyte, comprises a material selected i.e. polypropylene membrane. The electrolyte comprises an aqueous solution of a compound selected from the group consisting of sulfuric acid, potassium hydroxide, and sodium hydroxide. The electrode materials comprises of Polypyrrole Conducting Polymer-Carbon Substrates Composites. The Carbon Substrates are amine functionalized multiwalled Carbon nanotubes (AMWCNTs), GR or HC. The working electrodes were prepared by mixing the synthesized electrode materials, activated charcoal, and poly (vinyldieneflouride) (PVDF) with a mass ratio of 70:20:10. A small amount of N, N dimethylformamide was added to obtain homogenous slurry of electrode materials, which was subsequently painted on a graphite sheet (3×3 cm2) by brush and allowed to dry at 65?C in vacuum for 24 h.

[0044] The supercapacitive studies of electrode materials was done by Electrochemical workstation Metrohm AUT86472 (Netherland) at ambient temperature via 3-Electrode and 2-Electrode cell.

[0045] In sum, the Polypyrrole and polypyrrole-amine functionalized multiwalled carbon nanotube, graphene and hybrid carbon assemblage (AMWCNTs+GR) composites were prepared via in-situ polymerization of pyrrole dispersed onto carbon nanotubes, graphene and hybrid carbon assemblage. The molar concentration of pyrrole was 0.015 – 0.04 M and the resulting composites were designated as PPy-CNT, PPy-GR and PPy-HC respectively. A typical preparation protocol for the preparation of composites was described as following. The freshly distilled pyrrole (0.015 – 0.04) was injected into a suspension of different carbon substrates (0.05 – 0.2 g) in 10 – 30 % methanol solution. The suspension was ultrasonicated for 30 ~ 70 min prior to cooling in an ice bath for uniform dispersion. The reaction was then slowly added with an equivalent FeCl3 (0.3 – 0.6 g in 1 M HCl) solution and allowed to proceed at 0–10?C for 24 h. After filtration, the title composite was washed subsequently with ethanol and water several times, and the product was dried at overnight in vacuum. All as-prepared composites were kept in cool place for followed characterization. Sodium dodecyl benzene sulfonate (NaDBS) (0.005 – 0.02 M) doped polypyrrole and composites were prepared with similar method as mentioned in above protocol.

[0046] The present invention thus differs from the patent application number 201811009209 principally by the surfactant used as dopant, which is Sodium lauryl sulphate (SLS) in 201811009209, and sodium dodecyl benzene sulphonate (NaDBS) in the Patent of Addition.

[0047] Polypyrrole based composites were synthesized by chemical oxidative polymerisation while surfactant doped based PPy composites were prepared by in-situ emulsion polymerisation. Surfactants, Sodium lauryl sulphate (SLS) and sodium dodecyl benzene sulphonate (NaDBS) also act as emulsifier within the polymerisation reaction. Study has been performed to check the effect of surfactant doping on the pseudocapacitance of the conducting polymer, PPy, and improvement in the specific capacitance of composite electrode materials for supercapacitor.

[0048] The following examples are given to illustrate the process of the present invention and should not be construed to limit the scope of the present invention:
Example 1:
Synthesis of Polypyrrole and Sodium dodecyl benzene sulphonate doped Poypyrrole coated over three different carbon substrates:
[0049] The Polypyrrole and polypyrrole-amine functionalized multiwalled carbon nanotube, graphene and hybrid carbon assemblage (AMWCNTs+GR) composites were prepared via in-situ polymerization of pyrrole dispersed onto carbon nanotubes, graphene and hybrid carbon assemblage. The molar concentration of pyrrole was 0.025M and the resulting composites were designated as PPy-CNT, PPy-GR and PPy-HC respectively. A typical preparation protocol for the preparation of composites was described as following. The freshly distilled pyrrole (0.025M) was injected into a suspension of different carbon substrates (0.1g) in 20% methanol solution. The suspension was ultrasonicated for 40 ~ 60 min prior to cooling in an ice bath for uniform dispersion. The reaction was then slowly added with an equivalent FeCl3 (0.49 g in 1 M HCl) solution and allowed to proceed at 0–5?C for 24 h. After filtration, the title composite was washed subsequently with ethanol and water several times, and the product was dried at overnight at 60?C in vacuum. All as-prepared composites were kept in cool place for followed characterization. Sodium dodecyl benzene sulfonate (NaDBS) (0.01M) doped polypyrrole and composites were prepared with similar method as mentioned in above protocol. It is observed that combination of FeCl3 and anionic surfactant NaDBS enhanced the conductivity as well as increased yield of resultant polymer. The resulting composites after surfactant doping were designated as DPPy, DPPy-CNT, DPPy-GR and DPPy-HC respectively.
Example 2:
Comparison of specific capacitance:
Table 1:
Summary of specific capacitance of undoped PPy and composites
Scan Rate (mV/sec) Specific Capacitance of PPy and composites from CV curves in F/g
PPy PPy-CNT PPy-GR PPy-HC
5 107 173 267 356
10 86 102 193 289
25 51 77 112 207
50 42 56 88 168
100 23 39 69 104

Table 2:
Summary of specific capacitance of NaDBS doped PPy and composites
Scan Rate (mV/sec) Specific Capacitance of DPPy and composites from CV curves in F/g
DPPy DPPy-CNT DPPy-GR DPPy-HC
5 193 232 317 473
10 116 191 251 392
25 83 122 203 316
50 58 87 154 247
100 40 54 110 194

Table 3:
Summary of specific capacitance of PPy and composites from GCD curves
Current Density (A/g) Specific Capacitance of PPy composites in F/g
PPy PPy-CNT PPy-GR PPy-HC
1 87 168 202 252
1.5 54 102 121 166
2 39 71 89 106

Table 4:
Summary of specific capacitance of NaDBS doped PPy and composites from GCD Curves
Current Density (A/g) Specific Capacitance of NaDBS Doped PPy composites in F/g
DPPy DPPy-CNT DPPy-GR DPPy-HC
1 217 278 403 587
1.5 104 179 311 359
2 69 121 229 279

Table 5:
Summary of Impedimetric parameters
Electrode Impedimetric Parameters
Rs (O) Rct (O)
PPy 6.9 5.3
DPPy 5.6 4.1
PPy-CNT 4.8 3.2
DPPy-CNT 3.6 2.5
PPy-GR 2.7 2.2
DPPy-GR 2.1 1.9
PPy-HC 1.6 1.2
DPPy-HC 1.3 1.1

Table 6:
Summary of Energy Density of undoped PPY and composites
Current Density (A/g) Energy Density of PPy and composites in Wh/Kg
PPy PPy-CNT PPy-GR PPy-HC
1 48.33 93.33 112.22 140
1.5 30 56.6 67.22 96
2 21.6 39.44 49.44 58.88

Table 7
Summary of Energy Density of doped PPY and composites
Current Density (A/g) Energy Density of NaDBS Doped PPy and composites in Wh/Kg
DPPy DPPy-CNT DPPy-GR DPPy-HC
1 120 154.44 223.88 326.11
1.5 57.77 99.44 172.77 199
2 38.33 67.22 127.22 155

Table 8:
Summary of Power Density of undoped PPY and composites
Current Density (A/g) Power Density of PPy and composites in W/Kg
PPy PPy-CNT PPy-GR PPy-HC
1 659 739 884 933
1.5 940 1210 1476 1728
2 1590 1910 2189 2790

Table 9:
Summary of Power Density of doped PPY and composites
Current Density (A/g) Power Density of NaDBS doped PPy and composites in W/Kg
DPPy DPPy-CNT DPPy-GR DPPy-HC
1 981 1110 1191 1262
1.5 1294 1711 2177 2830
2 1889 2313 2839.44 3853

[0050] Therefore, from the comparison of parameters, it has been found that the DPPy-HC is the best, and the method for preparing DPPy-HC may be considered the best mode of performing the present invention.

We Claim:
1. A process for preparing polypyrrole and sodium dodecyl benzene sulphonate doped polymer carbon substrate composite as supercapacitor electrode, said process comprising the steps of:
a) injecting 0.025M of pyrrole into a suspension of 0.05 – 0.5g of carbon substrates selected from carbon nanotubes (CNT) or graphene (GR) or hybrid carbon assemblage (HCA), preferably HCA in 10 – 40 % methanol solution;
b) adding with an equivalent 0.005 – 0.02M anionic surfactant Sodium dodecyl benzene sulfonate (NaDBS) and 0.005- 0.01M FeCl3 solution and allowed to proceed at 0–5 ºC for 24 hours;
c) filtering, washing subsequently with methanol and water; and
d) drying overnight at 60ºC in vacuum.
2. The process as claimed in claim 1, wherein pyrrole and NaDBS solution was ultrasonicated for 40 ~ 60 min prior to cooling in an ice bath for uniform dispersion.
3. The process as claimed in claim 1, wherein 0.49 g FeCl3 in 1 M HCl solution is prepared and allowed to proceed at 0–5ºC for 24 h followed by filtration, washing subsequently with ethanol and water, and drying overnight at 60ºC in vacuum.
4. The process as claimed in claim 1, wherein 0.1 g of carbon substrates, preferably HC is used.
5. The process as claimed in claim 1, wherein carbon substrate is dissolved in 20 % methanol solution.
6. The process as claimed in claim 1, wherein 0.01 M of NaDBS is used.