Hasiah Salleh

Study the Electrical Properties and the Efficiency of Polythiophene with Dye and Chlorophyll as Bulk Hetero-Junction Organic Solar Cell

The main focus in this work is to study the electrical properties and efficiency of the mixtureof organic materials that can absorb wide range of light spectrum. Polythiophene (PT) as the main active ingredient acts as a acceptor that absorb light in range 200 -350 nm, while the tris (8-hidroxyquinoline aluminum)(Alq3)and chlorophyll acts as a donor that can absorb light from 350 nm to 700 nm. The combination of PT:Alq3:Chlo is called as bulk heterojunction in organic solar cell.The thin film of the mixture was deposited by using spin coating technique. The energy gap and electrical conductivity of thin films were measured by UV-VIS and 4-point probe respectively. The efficiency of thin film solar cell was determined by 2-point probe. Result of energy band gap of PT:Alq3:Chlo thin film is about 3.72+ 0.02 eV. The electrical conductivity showed increase with the increasing of light intensity. The conductivity of PT:Alq3:Chlo thin film at ratio 3:1:2 under radiation of 100Wm-2 is about 0.250+ 0.001 Scm-1 andthe power conversion efficiency is ~7.16%.

Electrical Conductivity and Hall Effect Study of Organic Solar Cell Using Downy Rose Myrtle Berries as Natural Dye: A Heat Treatment

This work focused on the electrical and Hall Effect of Organic Solar cell (OSC). In this work, Indium Tin oxide (ITO) glass as substrate was heated at 50 °C to 200 °C. The polymer used was Poly (3-Dodecylthiophene) (P3DT) thin film and Downy Rose Myrtle berries (RhodomyrtusTomentosa(Ait.) Hassk.) as dye. The P3DT were deposited on the ITO substrate using electrochemistry method at room temperature. While, the dye of Downy Rose Myrtle berries was deposited by layered using spin coating method. The electrical conductivity of ITO deposited thin film was explored by four point probes (FPP) under dark and under light radiation (range of 10 Wm-2 to 200Wm-2). From FPP study, the electrical conductivity was increased by the increment of light intensity and temperature of substrate. Lastly, the samples were examined using Hall Effect measurement to obtain the type of sample, Hall mobility, and highest charge carrier in the sample of OSC. The results show that the sample is suitable for further solar cell application.

Synthesis, Characterization and Electrical Conductance of Ferrocenylazobenzene

Ferrocenylazobenzene was synthesized by condensing an aminoazobenzene dye with ferrocenecarboxylic acid previously treated with oxalyl chloride. The compound displayed an anticipated chemically reversible one-electron oxidation process and gave a formal potential, E° = 0.65 V. In the UV-Vis region, the azo π-π* and n-π* transitions appeared at 355 and 460 nm respectively. On oxidation of the ferrocenyl moiety, the azo π-π* band was blue-shifted to 348 nm with an increase in intensity, while a new broad, lower energy absorption band assigned to the ligand-to-metal charge transfer appeared at 622 nm. The growth of this new band was concurrent with the bleaching of the metal-to-ligand charge transfer band which was largely obscured by the azo n-π* band at 460 nm. The compound in the form of thin film gave an average electrical conductivity of 0.239 ± 0.001 Scm−1 and a non-linear I-V curve with knee voltage at 2.3 V in dark condition.

Scan rate effect of titania for hybrid solar cell applications: Structural and electrical study

The AIP In this research, hybrid solar cell are produce by a combination of organic (Areca Catechu) extraction and Poly (3-hexylthiophene) (P3HT) and inorganic Titanium Dioxide, TiO2 materials. These hybrid solar cells are fabricated accordingly by layered of ITO/TiO2/P3HT/Areca Catechu/Au by using electrochemical method. The deposition of each layered by EIS was different by varied the scan rate of TiO2 deposition which are 0.05, 0.07, 0.09 and 0.11 vs-1 whereas the number of scans of each layers are fixed to 5 numbers of scans. Nanocrystals TiO2 (anatase structured) was prepared by dissolving the TiO2 nanoparticles with acetic acid which acts as capping agent in order to gain TiO2 nanostructures with better-controlled size and shape. Field Emission Scanning Electron Microscope (FESEM) images indicates that the TiO2 nanoparticles size was found to be around 15-34 nm. The XRD patterns indicate that the TiO2 film was highly crystalline and the anatase structure of TiO2 remains unchanged after annealed proc...

Fabrication and characterization of titania/poly (3-dodecylthiopene)/red seaweed as hybrid solar cell

In this research, hybrid solar cells which consist of a combination of organic red seaweed (RS) (Kappaphycus alvarezii) and poly (3-dodecylthiophene) (P3DT) with inorganic titania nanocrystals (TiO2 NCs) materials are fabricated. These hybrid solar cells are fabricated in bilayer heterojunction of ITO/TiO2 NCs/P3DT/RS/Au via electrochemistry method using Electrochemical Impedance Spectroscopy (EIS). The optical, electrical properties and power conversion efficiency (PCE) of these hybrid solar cells that can absorb over a broad range of light spectrum were studied. The UV-Vis spectra showed that TiO2 NCs, P3DT and RS were absorbed over a wide range of light spectrum which were 200-300 nm, 300-900 nm and 250-670 nm; respectively. The FTIR spectra of the RS showed the presence of carbonyl and hydroxyl group which was responsible for a good sensitizer for these hybrid solar cells. The electrical conductivity of ITO/ (1) TiO2 NCs/P3DT/RS thin film under the light radiation of 100 Wm−2 was 0.288 Scm−1, while fo...

Hydrothermal temperature effect on crystal structures, optical properties and electrical conductivity of ZnO nanostructures

ZnO is an wide direct band gap semiconductor and possess rich family of nanostructures which turned to be a key role in the nanotechnology field of applications. Hydrothermal method was proven to be simple, robust and low cost among the reported methods to synthesize ZnO nanostructures. In this work, the properties of ZnO nanostructures were altered by varying temperatures of hydrothermal process. The changes in term of morphological, crystal structures, optical properties and electrical conductivity were investigated. A drastic change of ZnO nanostructures morphology and decreases of 002 diffraction peak were observed as the hydrothermal temperature increased. The band gap of samples decreased as the size of ZnO nanostructure increased, whereas the electrical conductivity had no influence on the band gap value but more on the morphology of ZnO nanostructures instead.

Hybrid thin films based on bilayer heterojunction of titania nanocrystals/polypyrrole/natural dyes (Kappaphycus alvarezii) materials

In this research, hybrid thin films which consist of a combination of organic red seaweed (RS) (Kappaphycus alvarezii) and polypyrrole (PPy) with inorganic titania nanocrystals (TiO2 NCs) materials were fabricated. These hybrid thin films were fabricated accordingly with bilayer heterojunction of ITO/TiO2 NCs/PPy/RS via electrochemical method using Electrochemical Impedance Spectroscopy (EIS). The effect of number of scans (thickness) of titania on optical and electrical properties of hybrid thin films were studied. TiO2 NCs function as an electron acceptor and electronic conductor. Meanwhile, PPy acts as holes conductor and RS dye acts as a photosensitizer enhances the optical and electrical properties of the thin films. The UV absorption spectrum of TiO2 NCs, PPy and RS are characterized by UV-Visible spectroscopy, while the functional group of RS was characterized by Fourier transform infrared spectroscopy (FTIR). The UV-Vis spectra showed that TiO2 NCs, PPy and RS were absorbed over a wide range of li...

Thickness Dependent on Energy Band Gap and Electrical Conductivity of Undoped Conjugated Polymer Thin Films

Conjugated polymers have been widely used for electronic purpose applications due to their numerous advantages. This has led many researches to pay their major attention in studying on characteristics of conjugated polymer thin films. The purpose of this study was to investigate the effect of undoped conjugated polymer thin films on their optical and electrical properties. Poly(3-thiophene acetic acid), Polypyrrole and Polythiophene thin film was fabricated on ITO glass substrate by using EIS. Film thickness, energy band gap and electrical conductivity of thin films were characterized by using profilometer, ultraviolet-visible spectrometer and four point probe method respectively. The thickness of each thin film varied between 50.534 nm to 97.03 nm. The result has shown that thicker film has lower energy band gap compared to the thinner one. However the electrical conductivity showed an opposite behavior.

Mixture of Zinc Oxide Microrod and Poly(3-Dodecylthiophene) with Melastoma malabathricum Dye for Hybrid Solar Cell

A single hybrid solar cell (SHSC) which consist of zinc oxide (ZnO) micro-rod and Poly (3-dodecylthiophene)(P3DDT) materials with nature dye from Melastomamalabathricum fruit (Mm) were fabricated to determine it electrical properties and power conversion efficiency (PCE). The ZnO microrod was growth by thermal method. P3DT was synthesis by oxidation polymerization method. Nature dye was extracted from Mm fruit in purplecolor.The fabrication of a SHSC started with growth ZnO microrodon the Indium Tin Oxide (ITO) in thin filmform, followed with P3DT layers and finally layered with Mm in 5 layers and 10 layers respectively.The SHSC wascharacterized the electrical conductivity and PCE also compared under dark condition and various light intensity. The conductivity of the samples is increase within the increment of light intensity and the efficiency of SHSC increase within the increment of layer of Mm. The highest electrical conductivity was for 10 layers of dye which is 2.678 + 0.002 Scm-1. The power conversion efficiency (PCE) of the ITO/ZnO/P3DDT/10 layers dye achieved was the highest which is 0.0011% under radiation of 200 Wm-2 intensity of light. As a conclusion, it can say that the amount of Mm can affect the performance of hybrid solar cell, where the dye is increased, the electrical conductivity and the PCE also increase. Thus, the Mm is a good dye and can be potential to apply in the solar cell.

Effect of Time Conditions on the Growth of ZnO Nanorods via Hydrothermal Method

In this study, ZnO nanorod arrays were fabricated using a hydrothermal method on ITO glass substrate. We can find that the dimension of ZnO nanorod will changes with different growth temperature. X-ray diffraction (XRD) patterns show that the nanorods are high-quality crystals growing along [00 direction with a high consistent orientation perpendicular to the substrate and it is also revealed that nanorods have wurtzite crystal structure. The diameter of ZnO nanorods were 100300 nm depending on the time of growth process. The surface morphology of ZnO nanorods were analyse using Scanning Electron Microscope (SEM).