Cyclic voltammetry can be used to investigate the chemical reactivity of species ion via oxidation and reduction process. The purpose of this study is to determine the level energy of high occupied ...molecule orbital (HOMO) and low unoccupied molecule orbital (LUMO) in polythiophene (PT), Poly (3-thiophene acetic acid) (P3TAA), polypyrrole (PPY) and chlorophyll (Chlo) through oxidation and reduction of molecular ions by cyclic voltammetry method. PT, P3TAA, PPY and Chlo solutions were prepared in a solvent of acetonitrile at the concentration range of 10-2 to 10-4 M. The current-voltage measurements for these solutions are performed using cyclic voltammetry method on input voltage from -2.0 V to 2.0 V. The working electrode used is indium tin oxide (ITO). The result of voltammogram is showed that the activity of PT species were produced three oxidation and one reduction processes. The formal reduction potential, Eo¢ is 0.83 (positive) meaning that oxidation process was dominant. So that the reaction of PT species was exhibited irreversible electrochemical behavior. The reaction of P3TAA species was exhibited reversible electrochemical behavior, where the range value of oxidation, DEpa and reduction, DEpc were in range of 0.825 V to 1.120 V and -0.230 V to 0.131 V respectively. PYY species reaction was exhibited irreversible electrochemical behavior where two oxidation states occur within -0.145 V to -0.202 V and 0.870 V to 1.63 V respectively. The species activity of Chlo was exhibited irreversible electrochemical behavior where only the oxidation process was obviously appeared at range of 0.80 V to 0.95 V. The LUMO energy levels of PT, P3TAA PPY and Chlo were 5.84 eV, 5.34 eV, 1.10 eV and 3.85 eV respectively, while HOMO energy levels of PT, P3TAA PPY and Chlo were 4.61 eV, 4.25eV, 3.70 eV and 5.93 eV. The average value of energy gap of PT, P3TAA, PPY and Chlo were 1.23 eV, 1.08 eV, 2.23 eV and 1.10 eV respectively.
The constant increase in worldwide per capita consumption of fish indicates the need for reliable and viable sources of fish, and aquaculture fits these criteria. Aquaculture has continued to make a ...significant contribution to total fisheries production over the last few decades. The significant progress in aquaculture has been largely attributed to the intensification of production and increasing dependency on formulated food. Among the major challenges in aquaculture is aquaculture feed, or in short, aquafeed, which may represent up to 80% of total operational costs. Due to escalating prices and unsustainable resources of aquafeed ingredients, especially fish meal, fish oils, and soybean meal, many substitutes are utilised, mainly animal by-products and animal waste, which is a concern under Islamic jurisprudence. This concern is quite substantial if aquaculture producers are vying for the halal market. Hence, it is important for them to understand this aspect of Islamic law. This paper reviews the current status of aquafeed ingredients and the classical Islamic jurisprudence pertaining to this issue. References to current decrees and standards by major Muslim countries and Islamic authorities are also presented, followed by options and avenues for remediation.
Hybrid solar cell (HSC) in a form of novel photovoltaic is considered among promising research topic due to its low cost's preparation and environmental friendly solar cells. This paper concerns a ...systematic study on concentration of TiO2 and effect of coating techniques towards solar cells's efficiency. However, this paper is limited to doctor blade and spin coating techniques only. These samples were then characterised based on morphology, thickness, optical absorption, electrical conductivity and solar cell's efficiency using various techniques including FESEM, profilometer, UV-Vis and, autolab with irradiance of 100 mW/m2. From the results, TiO2/PEDOT:PSS with dye Eugenia clavifora (EC) obtained the highest efficiency of 1.33% using doctor blade technique compared to 0.00108% for spin coating technique. Sample thickness was obtained at 60.25 ± 1.20 nm corresponding to the concentration of TiO2 at 0.20 M. Thus, it can be conclude that, power conversion efficiency (PCE) was dependent to the deposition techniques of the thin film.
High performances of Hybrid Dye Sensitized Solar Cell are necessary in absorbing more sunlight and needed renewable energy source to replace depleted fossil fuels via green energy. Hybrid DSSC is ...another promising option towards green energy to explore. This research aims, i) to study conjugated chlorophyll in order to increase charge carrier in molecule structure besides, increase the absorption spectrum via conjugating process with the addition of different amount Ferric (III) Chloride (FeCl3) acting as catalyst and, ii) to determine the effect of FeCl3 on the performance of conjugated dye as sensitizers in Hybrid DSSC. The conjugated chlorophyll shows a using UV-Visible analysis corresponding to conjugated chlorophyll absorbed in high region called red shifted which the maximum absorption obtain at a wavelength of 360nm and 311nm. Fourier Transform Infra-Red characterization of the an existing Fe-O bond appears at 430 cm-1 to 445 cm-1 and C≡C bond at 2244 cm-1 to 2260 cm-1. 10% FeCl3 in conjugated chlorophyll produce huge impact to electrical conductivity and efficiency with the highest value; 0.114 S/cm and 0.14%; respectively. Thus, it can be conclude that 10% FeCl3 of conjugated chlorophyll – Imperata cylindrica (iCHLO-IC) was suitable to be used for the next generation of hybrid DSSC.
PDF
