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A synthesis of electrode material with higher‐energy density and more extended stability is very significant for replacing the present‐day supercapacitor demand. Toward this objective, in this work, a composite containing three primary materials meant for supercapacitor application is synthesized. They are conducting polymer, metal oxide, and carbon materials. A unique quaternary composite is prepared via the chemical method using mesoporous carbon (MC), polyaniline (PANI), molybdenum oxide (MoO3), and silicon dioxide (SiO2) materials. This composite is used as an electroactive material in symmetric electrode configuration in aqueous electrolyte supercapacitor. As synthesized MoO3‐MC‐SiO2‐PANI sample is subjected to 250,000 CD cycles at a higher discharge current density of 16.6 A/g with 57% retention of the initial capacitance of 45 F/g with low and constant equivalent series resistance (ESR) value (3–3.8 Ω). This composite showed an energy density (ED) as 31 Wh/Kg at a power density of 155 W/Kg. The excellent stability of the electrode material was established by evaluating the electrode material after the subjection of 250,000 CD cycles by Fourier‐transform infrared spectroscopy (FT‐IR), field emission scanning electron microscopy (FE‐SEM), energy dispersive spectroscopy (EDX), cyclic voltammetry (CV), galvanostatic charge–discharge (CD), and electrochemical impedance spectroscopy (EIS) measurements. [ABSTRACT FROM AUTHOR]

Flexible electrode with high electrical conductivity and electrochemical performance are desirable today to meet the energy demand in portable electronics. Here we designed a flexible electrode, polyaniline‐sulfate‐titanium dioxide‐multiwalled carbon nanotubes (PANI‐SA⋅TiO2⋅MWCNT) to improve the electrochemical performance. This is achieved by following a synthetic strategy via the synthesis of PANI‐SA⋅TiO2⋅MWCNT by a two‐step process; initially, PANI‐SA⋅TiO2 synthesized by aqueous polymerization using two oxidants, namely peroxotitanium acid (PTiA) and ammonium persulfate (APS). Wherein, PTiA acts both as oxidant and source of TiO2. In the second step, emulsion polymerization of PANI‐SA⋅TiO2 with a small amount of MWCNT by benzoyl peroxide as oxidant. Formed PANI‐SA⋅TiO2⋅MWCNT was coated on a stainless steel foil without using any binder. Electrochemical performances of the electrodes of both PANI‐SA⋅TiO2 and PANI‐SA⋅TiO2⋅MWCNT were carried in symmetric cell supercapacitor configuration in aq. 1 M sulfuric acid electrolyte by cyclic voltammetry and charge‐discharge measurements. This composite exhibits an excellent rate capability, and no degradation was observed in specific capacitance over 5,000 charge‐discharge cycles carried even at a higher current density of 1.6 A g−1. The electrochemical performance of PANI‐SA⋅TiO2, including cycle life, is enhanced with the use of MWCNT. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, to make a stable electrode material for a supercapacitor, we selected a polyaniline and titanium dioxide (TiO2) hybrid material. Peroxotitanium acid was used to oxidize aniline in the presence of sulfuric acid to a poly(aniline sulfate) salt-titanium oxide composite in one step. IR, X-ray diffraction, and energy dispersive X-ray analysis (EDAX) analyses supported the formation of the composite. The poly(aniline sulfate) salt-titanium oxide composites (50 wt % each) showed an amorphous, flakelike morphology having a conductivity value of 8 × 10−3 S/cm with an excellent yield and stability (300°C).This composite material in the cell configuration showed a specific capacitance of 320 F/g at a 0.33 A/g discharge current density. Thirty thousand charge-discharge (CD) cycles at a heavy CD current density of 3.3 A/g were carried out on the supercapacitor cell. The values of equivalent series resistance (ESR) (8-9 Ω) and efficiency (100-98%) were found to be independent of the cycle number with an excellent retention capacity of 83%. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41711. [ABSTRACT FROM AUTHOR]