The annealing temperature for 250 nm PVDF-TrFE (70:30 mol %) spin coated thin films were varied at solvent evaporation (T s = 79 ˚C), Curie's transition (T c = 113 ˚C) , till melting temperature (T m = 154 ˚C). XRD measurement showed that, there was an improvement in the crystallinity of the annealed films, consistent with the increased in the annealing temperatures. Morphological studies of the annealed PVDF-TrFE thin films as observed with Field Emission Scanning Electron Microscope (FESEM) (100k magnification), showed enhanced development of elongated crystallite structures known as ferroelectric crystal. However, thin film annealed at 160 ˚C (AN160) showed fibrous-like structure with appearance of nanoscale separations, which suggested high possibility of defects. Ferroelectric characterization indicated an improvement in the remnant polarization of annealed PVDF-TrFE thin films with the exception to AN160 in which leakage of current was inevitable due to the presence of cracks on the film surface.

The different morphology of 250 nm PVDF-TrFE (70:30 mol%) thin films were observed in relation to its ferroelectricity. The annealing temperatures were varied from solvent evaporation (Ts), Curies transition (Tc), up to melting temperature (Tm). It was found that the annealing process promoted the development of elongated crystallite structure also known as ferroelectric crystal, which significantly improved the ferroelectric properties of PVDF-TrFE (70:30 mol%) thin films. However, the presence of nanoscale separations on the thin film annealed over Tm (AN160) suggested high possibility of defects, and hence a reduction in ferroelectric properties of thin films.

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The annealing temperature of 250nm PVDF-TrFE (70:30 mol%) spin coated thin films were optimized. The annealing temperature were varies starting from solvent evaporation (T s ), Curie's transition (T c ), up to melting temperature (T m ). The result shows that the dielectric constant increases with the increasing of annealing temperature. Supported with the XRD observation indicating there were an improvement in crystallinity consistently with the increasing of the annealing temperature. Morphological properties of the annealed PVDF-TrFE thin films were observed by utilizing Field Emission Scanning Electron Microscope (FESEM) at 100k magnification. It can be found that, the annealing temperature promotes the development of elongated crystallite structure which known as ferroelectric crystal. However, the presence of nanoscale cracks on the thin film annealed at 160˚C (AN160, over T m ) suggesting high possibility to posed defects while in device applications.

The ability to decorate silicate surface with different organoalkoxysilanes creates powerful new capabilities for catalyst, adsorbents and chemical separation. Mesopororus silica, MCM-41 was modified by grafting of amino and mercaptopropyl functional group. The structures of these materials were characterized by using Fourier Transform Infrared Spectroscopy (FT-IR), and X-Ray diffraction (XRD). The samples were found to exhibit structural properties similar to those reported earlier. Significant functional groups of the modified mesoporous silicates were found in the spectrum of FT-IR. Standard structure of mesoporous silicates were found to be preserved at planar [100] of XRD difractogram of mesoporous silicates. Adsorption of Cu (II) ions were done under different temperatures, initial concentrations and pH. Adsorption process also was determined from kinetic point of view and was found to be better fitted to pseudo second order of kinetic model.