XRD and surface morphology studies on chitosan-based film electrolytes

• Published in: Journal of Applied Sciences
• Main Author: Yahya M.Z.A.; Harun M.K.; Ali A.M.M.; Mohammat M.F.; Hanafiah M.A.K.M.; Ibrahim S.C.; Mustaffa M.; Darus Z.M.; Latif F.
• Format: Article
• Language: English
• Published: Asian Network for Scientific Information 2006
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-33845872808&doi=10.3923%2fjas.2006.3150.3154&partnerID=40&md5=b6da7e6d29c3bd2fd16ac3a50ebb13e0

Chitosan was used as the host polymer with lithium acetate (LiOAc) as the doping salt and Palmitic Acid (PA) and Oleic Acid (OA) as plasticizers. The highest conductivity value was obtained for film containing salt 55 wt. % CA and 45 wt. % LiOAc. At this composition, the surface of the film shows clusters of needle or dendrite-like structures. The x-ray diffractogram shows peaks at 2θ = 16°, 21°, 26° and 31° attributed to the salt. The peaks are small and relatively broad in comparison to sample with equal amounts of polymer and salt. The surface of the film shows that the salt has recrystallized out of the film. This could reduce the number of mobile lithium ions in the film and thus lower the conductivity of this sample. Both films formed from solution containing 1.0 g chitosan +0.20 g oleic acid and containing 1.0 g chitosan +0.40 g oleic acid have a porous surface. Such films could be suitable as a separator for lithium ion cells. This surface morphology is different from those films obtained from a solution containing 1.0 g chitosan +0.40 g ethylene carbonate. The highest conducting OA plasticized film contains 50 wt. % CA, 40 wt. % LiOAc and 10 wt. % OA. The surface looks soft and spongy with tunnel-like structures. © 2006 Asian Network for Scientific Information.