Supercapacitors composite solid polymer

Electronically conducting polymers (ECPs) such as polyaniline (PANI), polypyrrole (PPy) and po 1 y(3.4-cthy 1 cncdi oxyth iophcnc) (PEDOT) have been applied in supercapacitors, due to their excellent electrochemical properties and lower cost than other ECPs. We demonstrated that multi-walled carbon nanotubes (CNTs) prepared by catalytic decomposition of acetylene in a solid solution are very effective conductivity additives in composite materials based on ECPs. In this paper, we show that a successful application of ECPs in supercapacitor technologies could be possible only in an asymmetric configuration, i.e. with electrodes of different nature. 

A. Yoshizawa, M. Takeda, Y. Oura, Y. Takemoto and K. Naoi, Low-molecular-weight soluble polyaniline for electrolytic capacitor, Electrochemistry, 1999, 67, 45 H. Yamamoto, K. Kanemoto, M. Oshima and I. Isa, Self-healing characteristics of solid electrolytic capacitor with polypyrrole electrolyte, Electrochemistry, 1999, 67, 855 M. Mastragostino, R. Paraventi and A. Zanelli, Supercapacitors based on composite polymer electrodes, J. Electrochem. Soc., 2000,147, 3167. 

Typically, the solid-state electrolyte can function as both a substrate and separator in the fabrication of a flexible supercapacitor by two steps. For instance, a freestanding PVA/ H3PO4 film was obtained by first casting the gel electrolyte on a glass slide and then peeled off from the glass. It had been further sandwiched between two composite electrodes that were prepared from conducting polymers and nanoparticles to produce the flexible supercapacitor (Fig. 9.3G) (Liu et al., 2010,2013b). 

FIGURE 2.81 Schematic diagrams of (a) dry solid-state polymer electrolyte (e.g., PEO/Li+), (b) gel polymer electrolyte, and (c) polyelectrolyte. (Zhong, C. et al. 2015. A review of electrolyte materials and compositions for electrochemical supercapacitors. Chemical Society Reviews 44 7484-7539. Reproduced by permission of The Royal Society of Chemistry.)... 

Hashmi and Upadhyaya compared the electrochemical properties of the electrochemically synthesized MnO /PPy composite electrodes, fabricated with different electrolytes, namely polymer electrolyte film (polyvinyl alcohol [PVA]-HjPO aqueous blend), aprotic liquid electrolyte (LiClO -propylene carbonate [PC]), and polymeric gel electrolyte (poly methyl methacrylate [PMMA]-ethylene carbonate [EC]-PC-NaClO ) [60]. The cell with aqueous PVA-H PO showed non-capacitive behavior owing to some reversible chemical reaction of MnO with water, while the MnO / PPy composite was found to be a suitable electrode material for redox supercapacitors with aprotic (non-aqueous) electrolytes. The solid-state supercapacitor based on the MnO /PPy composite electrodes with gel... 

An all-solid state supercapacitor was made using phosphoric acid-doped PBI as the polymer electrolyte membrane, and hydrous RuOi/carbon composite electrodes (20 wt%) with surface area 250 m /g. PBI was synthesized from diaminobenzidene (DAB) and isophthalic acid using polyphosphoric acid (PPA) as the solvent at 200 °C for 20 h as shown here ... 

Abstract This chapter details the preparation and mechanism of polymer electrolytes and their applications in electrochemical fields, such as lithium ion batteries, fuel cells, alkahne batteries, supercapacitors, solar cells, electrochromic devices and the like. Polymer electrolytes used in lithium ion batteries are divided into three categories solid, gel and composites. Recent progress made in these three categories is highlighted. Moreover, in addition to the lithium ion battery, appUcations of polymer electrolytes in other electrochemical fields and their ion conducting performance are also briefly described. 

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