Solid polymer electrolytes based in sodium alginate. / Eletrólitos sólidos poliméricos a base de alginato de sódio

AUTOR(ES)

Yurika Okamoto Iwaki

DATA DE PUBLICAÇÃO

2010

RESUMO

The aim of this study was the preparation and characterization of sodium alginate membranes plasticized with glycerol. The samples were obtained with different concentration of acetic acid or lithium perchlorate in order to use them as solid polymer electrolytes (SPE) in electrochemical devices, such as sensors and batteries. The films were characterized by elemental analysis (EA), scanning electron microscopy (SEM), X-ray, thermogravimetry (TG), dynamic-mechanical thermal analysis (DMTA), UV-visible spectroscopy, infrared spectroscopy (IR) and electrochemical impedance spectroscopy (IES). The samples plasticized with 0.6 g of glycerol showed good transparency, good ionic conductivity and flexibility. X-ray diffractograms evidenced predominantly amorphous state of the samples. The best ionic conductivity results of 8.7 x 10 -5 S cm -1 at room temperature and 1.15 x 10 - 3 S cm -1 at 80 ° C were obtained with sodium alginate samples containing 0.3 mL of acetic acid. Samples with larger amounts of acid became brittle and opaque. The best conductivity values of 3.1 x10 -4 S cm -1 at room temperature and 1, 2 x10 -3 S cm -1 at 80 ° C were obtained for the samples containing 15 wt.% of lithium perchlorate.. The analysis of the conductivity as a function of temperature revealed that they follow the Vogel-Tamman-Fulcher (VTF) conductivity model. The activation energy were 36, 14 kJ mol -1 for the sample with 0.3 mL of acetic acid and 36 kJ mol -1 for the sample with 0.4 mL of acid. The sample with 15 wt.% of lithium perchlorate showed activation energy of 18.43 kJ mol -1. This new ionic conducting membranes are good candidates to be used as electrolytes in electrochemical devices.

ASSUNTO(S)

polímeros naturais alginato de sódio eletrólitos sólidos poliméricos natural polymers solid polymer electrolytes sodium alginate ionic conductivity condutividade iônica

Documentos Relacionados

• Solid polymer electrolytes based on polysacharide: synthesis and characterization.
• "Electrochromic devices with solid polymeric electrolytes based on starch"
• Eletrólitos sólidos poliméricos a base de quitosana
• Preparation and characterization solid polymer electrolytes based of commercial gelatin for application in solar cells.
• "Eletrólitos sólidos cerâmicos à base de óxido de zircônio para a detecção de oxigênio"