Disulfide-Containing Crosslinked Polyaniline Cathode for Rechargeable Battery.

Polymer electrodes have had several advantages like being environment friendly, mechanically flexible and more inexpensive than lithium metal which is used as lithium metal oxide-based cathode. But polymer electrodes generally have had lower charge/discharge capacity. Sulfur compounds with organothiol (-SH) or disulfide (S-S) group have advantages about high theoretical capacity but they have poor electronic conductivity. Then in this study, focusing on the enhancement of electrical performance of polymer electrode, disulfide bonds are linked to the side chain of polyaniline (PANI) and conjugated crosslinking between polymer chains is formed. As a result, crosslinked poly(9-amino-5,8-dihydro-1H,4H-2,3,6,7-tetrathia-anthracene) (PADTTAA)-co-PANI electrodes with different ratio of ADTTAA were successfully synthesized. Elemental and compositional analysis on the surface of the polymer sample was measured by using X-ray photoelectron spectroscopy (XPS). And the electrochemical property of disulfide-containing crosslinked PANI based cathode was investigated by confirming cyclic voltammetry and charge-discharge capacity. As the contents of ADTTAA increased, the charge/discharge capacity increased but the conductivity and cycle life decreased.

Polymer Nanocomposite Electrode Consisting of Polyaniline and Modified Multi-Walled Carbon Nanotube for Rechargeable Battery.

In this study, PANI nanocomposite with modified multi-walled carbon nanotube (mMWCNT) was prepared. Herein MWCNT was modified by Friedel-Crafts acylation reaction. The dc conductivity of PANI nanocomposite according to the content of mMWCNT was measured by four-point probe. The highest conductivity of 9.49 S/cm was obtained in case of PANI nanocomposite with 3 wt% of mMWCNT. And it could be known that MWCNT was less damaged by the modification of Friedel-Crafts acylation reaction (mMWCNT) than strong acid treatment (aMWCNT), so the thermal stability of PANI nanocomposite was higher than that of pure PANI. And the morphology and crystallinity of the PANI nanocomposite were investigated by field emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM) and X-ray diffraction. Also the electrochemical property of PANI nanocomposite was intensively investigated by cyclic voltammetry (CV) and charge-discharge capacity. From the CV data, it could be known that the charge-discharge capacity of PANI nanocomposite electrode was improved compared to pure PANI and PANI + aMWCNT electrodes.