| dc.description.abstract | Organic-inorganic nano-composite bring lots of improvements in electric and thermal properties, such as excellent mechanical stability, higher ionic conductivity and wide electrochemical stability, and also provide better interface stability with electrode.
This research focus on the preparation of TiO2 nano-tube and surface modification of TiO2 nano-tube with polymer which can be characterized by using XRD, NMR, XPS, TEM and TGA etc. Composite polymer electrolyte made by surface modified TiO2 nano-tube exhibit better compatibility from SEM surface morphology observation and an increase in ionic conductivity more than one order than that of blending ones. XPS and FT-IR also indicated polymer electrolyte containing TiO2 nano-tube can efficaciously dissociate the lithium salt and decrease the ion-pairing occurring.
Composite polymer electrolyte made with a number of variable components were systematically study to find their impact upon the electrochemical properties of the resulting materials. TiO2 nano-tube surface group can act as a cross-linking center for the polymer segments, which reduced the polymer reorganization, increased amorphous domain and delay the rate of recrystallization. It’s generally observed the lower molecular weight samples yielded the higher ionic conductivity. A proper choice of solvent will not only increase the order of salt dissociation but also can be stored in TiO2 tubular microstructure. Conductivity behavior suggested specific salt will re-distribute between TiO2 nano-tube and polymer chain to reach equilibrium state. TiO2 nano-tube with different `concentration of surface defect will be a critical factor affect the conductivity and thermal proper of polymer electrolyte.
In the composite/cross-linking polymer electrolyte, the interpenetrating network structure between phenolic and polymer chain can be efficiently hindered polymer crystallization, the cross-linker promoted mechanical stability, and the using of TiO2 nano-tube avoid the dramatically fadedness of conductivity came from over cross-linking. | en_US |