Zinc Oxide Nanostructures for Efficient Energy Conversion in Organic Solar Cell
Pages 31-35
M.F. Nurfazliana, S.A. Kamaruddin, M.S. Alias, N. Nafarizal, H. Saim and M.Z. Sahdan

DOI: http://dx.doi.org/10.6000/1929-6002.2014.03.01.5

Published: 01 April 2014

Abstract: We present a new approach of solution-processed using zinc oxide (ZnO) nanostructures as extraction layer material for organic solar cells. It is low chemical reaction compatibility with all types of organic blends and its good adhesion to both surfaces of ITO/glass substrate and the active layer (blends). Parameters such as the thickness and the morphology of the films were investigated to prove that these factors greatly affect the efficiency of organic solar cells. In this work, ZnO layer with thickness of approximately 53 nm was used as an interlayer to prevent pin-holes between the electrode and the polymer layer. The polymer layer was coated on the ZnO layer with the thickness of about 150 nm. The thick polymer layer will form a non-uniform surface because of the solvent, 1-2dichlorobenzene will etch away some region of the polymer layer and forming pin-holes. ZnO nanostructures layer was used to prevent pin-holes between the polymer layer and electrode. From the surface morphology of ZnO layer, it shows a uniform surface with particle grain size obtained between 50 -100 nm. The presence of the interlayer has a positive effect on the electrical characteristics of the solar cells. It was found that an organic solar cell with thickness less than 150 nm shows the optimum performance with efficiency of 0.0067% and Fill Factor (FF) of about 19.73.

Review on Air Cathode in Li-Air Batteries
Pages 293-305
Zhaoru Zha, Cai Shen, Deyu Wang and Wei-Qiang Han

DOI: http://dx.doi.org/10.6000/1929-6002.2013.02.04.1

Published: 29 November 2013

Abstract: Lithium-air (Li-air) battery is a promising electrochemical system with unprecedented high energy density. However, many problems and challenges prevent its wide scale application and commercialization. Low oxygen diffusion rates and large voltage gap are two of the main problems in Li-air battery. These two problems are related to the materials used in the air cathode such as porous carbon materials and metallic catalysts. This review seeks to discuss various materials used in the air cathode for Li air batteries. Mechanism of reaction in air cathode will be elucidated and discussed.

Study of Biodiesel Production from Sunflower Oil Using Non Usual Basic Polymeric Resin as Catalyst
Pages 130-138
Viviane Fernandes da Silva, Luiz Claudio de Santa Maria, Lenise V.F. Gonçalves, Maurício G. Fonseca and Luciano N. Batista

DOI: http://dx.doi.org/10.6000/1929-6002.2013.02.02.5

Published: 20 May 2013

Abstract: Biodiesel is defined as a long-chain mono alkyl (methyl, ethyl or propyl) ester of fatty acids obtained from renewable sources by transesterification reaction using an acid or base. In this work, a basic resin, Amberlyst A26, was used to produce methyl sunflower biodiesel. The iodine value, corrosion to copper, oxidative stability, specific mass, water content, acid value, cloud point and ester composition were evaluated. The heterogeneous catalyst was also characterized to verify its efficiency and its ability to be reused. We used the following analytical techniques: scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-rays fluorescence (XRF) and differential scanning calorimetry (DSC). The results showed that the characteristics of biodiesel made from sunflower oil using resin A26 as a catalyst are in accordance with Brazilian biodiesel regulations, except the oxidative stability. The techniques used to characterize the resin showed that it is possible to reuse the resin after regeneration.

Kitchen Waste Residues as Potential Renewable Biomass Resources for the Production of Multiple Fungal Carbohydrases and Second Generation Bioethanol
Pages 186-200
Chetna Janveja, Susheel Singh Rana and Sanjeev Kumar Soni

DOI: http://dx.doi.org/10.6000/1929-6002.2013.02.02.11

Published: 20 May 2013

Abstract: Utilization of kitchen waste, the major portion of municipal solid waste for the coproduction of multiple carbohydrases and bioethanol was investigated in this study. Solid-state fermentation was performed to evaluate the potential of various steam pretreated kitchen waste residues as substrates for the coproduction of cellulolytic, hemicellulolytic, pectinolytic, amylolytic enzymes by a locally isolated strain of Aspergillus niger CJ-5. All the kitchen waste residues simply moistened with water,without the supplementationofexogenous nutrients proved good for the induction of all the enzyme components of a cocktail after96 h incubation. Of all the substrates evaluated, steam pretreated potato peels induced maximum yields corresponding to 69.0±1.92U CMCase, 16.5±0.54U FPase, 44.0±1.28U β-glucosidase, 999.0±28.90U xylanase, 58.2±2.12U mannanase, 120.0±3.72U pectinase, 31520.0±375.78U α-amylase, 482.8±9.82U glucoamylase/g dry substrate (gds). Saccharification of residues using inhouse produced crude enzyme cocktail resulted in the release of 610±10.56, 570±8.89, 435±6.54, 475±4.56, 445±4.27, 385±4.49, 370±6.89, 490±10.45 mg of total reducing sugars/g of dried potato peels, orange peels, pineapple peels, mausami peels, onion peels, banana stalks, pea pods and composite mixture respectively revealing carbohydrate conversion efficiencies in the range of 97.0-99.4%. After fermentation of released hexoses, alcohol yields ranging from 80±1.069 - 262±7.86 µL/gds were obtained.