Aadila Aziz

Ionic conductivity studies of epoxidized poly (methyl methacrylate)-grafted natural rubber based gel polymer electrolyte for dye sensitized polymer solar cell

The epoxidized 30% PMMA grafted natural rubber (EMG30) was prepared using performic epoxidation method. 1HNMR studies confirm the appearance of epoxy group at 2.71 ppm in MG30 structure. The highest epoxidation content in EMG30 was used as a polymer host in gel polymer electrolyte (GPE) system. GPE film was prepared using 62.3 mol % EMG30, lithium trifluoromethanesulfonate (LiCF3SO3) and ethylene carbonate (EC). The conductivity of these polymer electrolytes was studied by AC impedance spectroscopy. The highest value was achieved up to 4.83 × 10−3 S cm−1 at 50 wt. % of EC in EMG30-LiCF3SO3 system. The increase in conductivity is associated to the increase of the segmental chain flexibility of the plasticized film indeed increases of the amorphous domain and was confirmed by X-ray diffraction (XRD) and differential scanning calorimetry (DSC) studies. These results show that this GPE system is a suitable candidate for use as an electrolyte in dye-sensitized polymer solar cell.The epoxidized 30% PMMA grafted natural rubber (EMG30) was prepared using performic epoxidation method. 1HNMR studies confirm the appearance of epoxy group at 2.71 ppm in MG30 structure. The highest epoxidation content in EMG30 was used as a polymer host in gel polymer electrolyte (GPE) system. GPE film was prepared using 62.3 mol % EMG30, lithium trifluoromethanesulfonate (LiCF3SO3) and ethylene carbonate (EC). The conductivity of these polymer electrolytes was studied by AC impedance spectroscopy. The highest value was achieved up to 4.83 × 10−3 S cm−1 at 50 wt. % of EC in EMG30-LiCF3SO3 system. The increase in conductivity is associated to the increase of the segmental chain flexibility of the plasticized film indeed increases of the amorphous domain and was confirmed by X-ray diffraction (XRD) and differential scanning calorimetry (DSC) studies. These results show that this GPE system is a suitable candidate for use as an electrolyte in dye-sensitized polymer solar cell.

Low Temperature Growth and Optical Properties of Zinc Oxide Nanostructure Prepared by Two-Step Solution-Based Deposition Method

ZnO thin films with typical c-axis (0 0 2) orientation were successfully deposited on glass substrates by two-step deposition method; mist-atomization and solution-immersion. The samples were annealed at selected temperature range of 350-500 ᵒC. The prepared samples then analyzed by Raman spectroscopy and photoluminescence (PL) spectroscopy. The optical properties of the samples were studied. The results of different annealing temperatures are also compared to investigate the optical and physical properties of each sample. Photoluminescence (PL) spectra showed low intensity in UV emission and high intensity in the visible emission, which indicates a good surface morphology of the ZnO nanorod. The Raman intensity changes in all sample were also tested.

Influence of Annealing Temperature to Surface Morphology of Flowerlike ZnO Deposited on Seeded Glass

Flower-shaped ZnO nanocrystals have been synthesized by a two-step solution based deposition method; mist-atomizer and solution-immersion on seeded glass substrate. The samples are annealed at different temperature in the range of 350 to 500 ᵒC. The structural properties of the samples were studied. Field emission scanning electron microscopy (FESEM) micrograph and atomic force microscopy (AFM) images for the ZnO thin films were obtained. Morphological changes due to various annealing temperature are discussed as changes observed in the ZnO crystals. FESEM image of the surface of the ZnO reveal the flowerlike vertical nanorods with hexagonal crossection. The samples with higher roughness analyzed from AFM images indicate that the sample have larger grain. AFM results are found in good agreement and supported the FESEM results.

Morphological, Structural and Optical Properties of Mg Doped ZnO Nanostructured Growth by Aqueous Solution Method

Mg doped Zinc oxide nanorods films were successfully deposited on glass substrate prepared by aqueous solution-immersion method. The influence of annealing temperature on the nanorod films were studied at different annealing temperatures 0°C, 250°C and 500°C respectively. FESEM showed the morphology of the films with hexagonal nanorods growth. XRD results indicated the crystalline structure of ZnO doped Mg nanorods films where the peak intensity of ZnO was decreased as annealing temperature increases. Photoluminescence (PL) measurement at room temperature showed the increasing of intensity peak for visible spectra with increasing of annealing temperature.

Optical Properties and Raman Scattering Investigation of Ag Doped ZnO Thin Film Prepared by Two-Step Solution-Based Deposition Method

Mist-atomization deposition method was applied in order to grow ZnO nanoparticles on Au-seeded glass substrates acting as seeded template. Ag doped ZnO thin films were deposited on ZnO seeded templates by solution-immersion method. The influence of Ag doping content on the optical and Raman scattering properties of ZnO films were systematically investigated by UV-Vis transmittance measurement measured by ultra-violet visible spectroscopy (UV-Vis) and Raman scattering spectrum measured by Raman spectroscopy under room temperature. From UV-Vis transmittance measurement, the incorporation of Ag dopant to the ZnO makes the transmittance wavelength shifted to the shorter wavelength as compared to the pure ZnO. From Raman spectra, 4 cm-1 downshift is observed in Ag-doped thin films as compared to pure ZnO thin films. This Raman peak shift shows that a tensile stress existed in the Ag-doped ZnO film.

Structural and Optical Properties of ZnO/PMMA Nanocomposite

UV filter is an interesting and challenging application in industries. Hence, ZnO-PMMA nanocomposite thin films have been chosen to achieve above mentioned characteristics [1]. In this study, fabrication of ZnO on PMMA glass substrate successfully prepared by using the solution-immersion method. Layer by layer of poly (methyl methacrylate) (PMMA) was deposited on a glass substrate using the spin coating technique by dissolving PMMA in toluene. Various layers of PMMA were varied to 1, 3, 5 and 7 layers. The structural and optical properties of ZnO/PMMA nanocomposite were then characterized by Field Emission Scanning Electron Microscope (FESEM) and Photoluminescene (PL) Spectroscopy. From FESEM result, shape of nanorod unclearly seen as the layer deposited of PMMA increase and from EDAX show oxygen element have highest atomic percentage 65.50 %. 7 layer of deposited PMMA show highest intensity compare to other layers in green region at 577.32 nm for PL measurement.

The Effect of PMMA Layer to the UV Properties of ZnO/PMMA Nanocomposite

Preparation of ZnO/PMMA nanocomposite has been reported by using the solution-immersion method. These studies involve depositing poly (methyl methacrylate) (PMMA) layer by layer on glass substrate using the spin coating technique. Surface morphologies deposited layer of PMMA on glass substrate was characterized using Atomic Force Microscope (AFM) and an optical property of ZnO/PMMA nanocomposite was characterized using UV-Vis Spectrometer. For AFM result, the highest surface roughness 0.048 nm represent layer of platinum due to its function as a seeded-catalyst followed by 1 layer of PMMA show surface roughness 0.015 nm. 4 hours immersion time show highest absorption for 5 layer of deposited PMMA at 279.21 nm. While, for 6 hours show highest absorption for 1 layer and 3 layer of PMMA with overlapped each other at 278.54 nm.

Preparation and Characterization of Needle-Like ZnO on TiO2 Nanoparticles by Solution-Immersion Method and RF Magnetron Sputtering

Needle-like zinc oxide (ZnO) nanostructures was deposited on titanium dioxide (TiO2) nanoparticles by solution-immersion method and Radio Frequency (RF) magnetron sputtering with diffferent RF powers, respectively on a glass substrate to synthesis nanocomposites of ZnO/TiO2. Field Emission Scanning Electrons Microscope (FESEM) images demonstrate that needle-like ZnO (112-1110 nm) are deposited on the surface of the TiO2 nanoparticles with the diameter of approximately 36.3-62.9 nm. At 200 W, more needle-like ZnO with smallest average diameter (112 nm) appeared on the TiO2 nanoparticles, which also has the smallest average size of 36.3 nm The compositions of elements in the nanocomposites were showed by Energy Dispersive X-ray Spectrometry (EDX). All elements of Ti, O, and Zn are observed as major components which confirm the presence of TiO2 and ZnO in the composite. X-ray Diffraction (XRD) patterns of the nanocomposites show ZnO formed on TiO2 nanoparticles are hexagonal with a wurtzite structure and it revealed ZnO/TiO2 thin films were succesfully deposited as nanocomposites of ZnTiO3 at 100 W, Zn2TiO4 at 150 W and Zn2Ti3O8 at 200 W and above.

Effects of RF Power on the Optical Properties of ZnO/TiO2 Nanocomposites Prepared by RF Magnetron Sputtering and Solution-Immersion Method

Nanocomposites of ZnO/TiO2 were fabricated by two methods. Firstly, deposition of TiO2 nanoparticles by Radio Frequency (RF) magnetron sputtering. Secondly, growths of ZnO nanostructures on the TiO2 nanoparticles by solution-immersion method with aqueous solution of Zinc nitrate hexahydrate as precursor solution and stabilizer hexamethylenetetramine (HMTA) in water as solvent. The optical properties of ZnO/TiO2 nanocomposites were examined by Ultraviolet-Visible (UV-Vis) spectroscopy, Raman spectroscopy and Photoluminescence (PL) spectroscopy. UV-vis spectra of ZnO/TiO2 nanocomposites display high absorption in the UV region and high transparency in the visible region. There is improvement in UV absorption for ZnO/TiO2 nanocomposites compared to pure TiO2 due to imperfect alignment of ZnO nanostructures. Raman analysis shows the presence of wurtzite hexagonal ZnO in all the films and presence of anatase structure of TiO2 in the film deposited at 200 W. PL spectra of the films show the emissions in the UV and visible regions. Intensity of PL emission in UV region (λ< 400 nm) is maximum for film deposited at 200 W and minimum for film deposited at 300 W resulting from the change in the surface state density. A broad peak from ~ 600-700 nm also was found for all the films.

The Growth of ZnO Nanoparticles by Solution-Immersion Method on Various Types of Seeded Template

Synthesis of nanostructured ZnO by an environmentally-friendly method thus applying water as the major media is the aim in solution-immersion method. In this paper, the effect of three types of seeded template to the structural and optical properties of ZnO nanostructures grown by the Solution-Immersion method is investigated. The primary template is glass, seeded with three types of thin films i.e. TiO2 by radio-frequency (RF) magnetron sputtering at 200 W (ZnO/TiO2), a layer of PMMA by spin-coating (ZnO/PMMA) and ZnO grown by the mist-atomization method (ZnO/ZnO). The morphology and optical properties will be investigated by FESEM, PL and UV-Vis.