Advanced Materials Research Vol. 1113

Abstract: Electrodeposition is a method to electrochemically deposit alloy on various types of metal. This method has ability to produce protective coating and thin films on the metal. In this research, one of the electrodeposition methods, Cyclic Voltammetry (CV) with 10 and 20 cycles was applied to deposit Cobalt-Nickel-Iron (Co-Ni-Fe) on Electroless Nickel Immersion Gold (ENIG) Flexible Printed Circuits (FPCs). The main purpose of this paper is to investigate the electrical properties, morphology and crystallographic structure of the electrodeposited coating. Curve Trace test was conducted to identify the contact resistance of the coating. In this case, the allowable contact resistance should be less or the same as ENIG FPCs which is 1.6 Ω. Morphology of the coated circuit was observed by using FESEM while crystallographic phase of the coating was identified by XRD. Morphology study on Co-Ni-Fe coated FPCs exhibited Cauliflower like shape with average grain size of 1.49 μm and 1.88 μm for 10 and 20 cycles, respectively. CoFe, FeNi and CoO.NiO phases was noticed in the electrodeposited coating. The obtained result showed that the electrodeposited Co-Ni-Fe produced with 10 cycles has the same contact resistance as ENIG which is 1.6 Ω. 20 cycles of CV produced 1.4 Ω of contact resistance, slightly smaller than the other FPCs. This research revealed that electrodeposited Co-Ni-Fe is suitable to be applied as a protective coating while still maintaining the electrical properties of FPCs.

Abstract: The present study shows the electrodeposition of MnO₂ from KMnO₂ solution and its electrochemical studies. XRD analysis shows the electrodeposited MnO₂ has nano-sized particle of 18 nm. The electrochemical properties have been investigated using the cyclic voltammetry, galvanostatic charge/discharge and impedance techniques. The electrodeposited MnO₂ shows good electrochemical behavior with high specific capacitance value of ca. 306 F g^-1. Moreover, it shows high capacitance stability of 90% over 1000 charge/discharge cycles. Impedance result shows low solution resistance and charge transfer resistance, an indication of the conductive nature for the electrodeposited film.

Abstract: With world-wide strict legislation for reduction or removal of lead from industrial waste, development of a large number of lead-free alternative solder materials had been intensively examined. The drive for lead-free solders development was towards systems that can imitate conventional lead containing solder alloys in terms of melting temperatures and improvement of mechanical properties. Nanostructured solder alloy, with a grain size of typically < 100 nm, was a new class of materials with properties distinct from and frequently distinguished to those of the conventional alloy. In comparison, nanostructured solder alloys exhibit higher strength and hardness, enhanced diffusivity, and excellent soft and hard magnetic properties. Numerous different techniques were performed to synthesize these nanostructured solder alloys. Electrodeposition method has generated huge interest in nanostructured solder preparation, mainly due to its ability to deposit solders selectively and uniformly at nanoscale. These factors bring significant influences on the behaviors of products, such as magnetization, density, ductility, wear resistance, corrosion resistance, porosity, molecular structure, and crystal properties which plays a vital part in the field of electronic manufacturing. In this paper, a short review on the electrodeposition, a useful technique to deposit different metals and alloys, as a method for nanostructured lead-free solder alloys preparation is presented.

Abstract: In this research, green synthesis of silver nanoparticles using elaeis guineensis leaves extract was investigated and the influence of pH and reaction time in the reaction kinetic were studied. UV-visible spectrophotometer was used to monitor the reduction reaction of silver ions to silver nanoparticles and formation of silver nanoparticles shown at sharp peak at pH 10 with λ_max of 391 nm. Transmission electron microscopy (TEM) shows silver nanoparticles are polydispersed and irregular shape with size ranging from 55-85 nm. Formation of silver nanoparticles was confirmed by energy dispersive x-ray analysis (EDAX) and crystalline structure using XRD. From this research, it was found that pH 10 influenced the reaction kinetic therefore reduce the reaction time.

Abstract: Textile industry is one of the most significant worldwide water pollution sources. With the increased demand for textile products, the textile industry and its wastewater have been increasing proportionally. Microcapsule has remarkable advantages in engineering application for pollutants removal as encapsulation agent of nanoparticles (NPs) to drastically reduce the risk associated to nanotoxicity when it is in direct contact with surroundings. This work primarily focuses on the synthesis of magnetic nanoparticles augmented microcapsule in which role of temperature and initial pH was studied in relation to Fenton reaction of Methylene Blue dye. It is observed that high removal efficiency of the dye could be achieved with high temperature whereas highly acidic and alkaline condition could enhance degradation rate. The inherent catalytic and magnetic properties exhibited by Fe⁰/iron oxides NPs-PVDF microcapsules, compared to conventional activated carbon based absorbent, make them an attractive candidate to remove cationic dye from aqueous environment.

Abstract: The application of photodegradable polyethylene is increasingly important for agricultural uses due to its ability to degrade after suggested shelf life and to counter measure pollution issue caused by conventional polyethylene films. The photodegradable polyethylene (PE) mixtures were formulated with added polypropylene (PP) and photodegradant (RM master batch) and tested in oil palm seedlings cultivation. PP is known to have photodegradable ability and RM master batch is proven to induce photo degradation of polyethylene. Thus, the mixture of these three components according to different ratios was processed into agricultural plastic films. There are four formulations that are tested in this study, namely T1 (80% PE:20% PP:5% RM master batch), T2 (70% PE:30% PP:5% RM master batch), T3 (80% PE:20% PP:3% RM master batch) and T4 (70% PE:30% PP:3% RM master batch). All formulations except control sample were added with photodegradant to impart degradation reaction and compatibiliser was also affixed to allow coalesce between polyethylene and polypropylene. Carbon black was added 0.5% into the formulation as for poly bags application, dark environment of soil is crucial for root development and growth. Penetration of sun light into the planting soil could commence development of shoot instead of root growth. All four formulations showed observable morphological changes on microscopic images on the surfaces after being used in oil palm nursery. From the study, it is shown that T1 and T3, with 20% of additional polypropylene had demonstrated clear surface disintegration when viewed microscopically. The addition of 3% and 5% of photodegradant into the formulations did not show any expressive difference thus suggesting that 3% of photodegradant is the optimum amount to induce photo degradation.

Abstract: The utilization of waste materials which are abundant and cheap, especially from clean resources, has become more pressing than ever. This paper, discusses the utilization of the wastes in the form of palm oil fuel ash and oil palm kernel shell in the production of mortar mixes as a part of new and innovative materials in construction industry. The studies include the basic properties including the morphology of the composite with regards to variations in the mix design process. In order to get a better performance in terms of strength development, the ash used has gone through heat treatment and ground up to the size less than 2µm. High volume of 60%, 80% and 100% palm oil fuel ash was used as cement replacement. The incorporation of more than 80% of palm oil biomass waste as cement and sand replacement has produced mortar having an improved compressive strength than normal mortar. In addition, the density of the mortar with biomass waste was less than normal mortar. Overall results have revealed that the inclusion of high volume palm oil biomass waste can produce mortar mix with high strength, good performance and most importantly more sustainable.

Abstract: Molecular self-assembly is ubiquitous in nature and has now emerged as a new approach in chemical synthesis, engineering, nanotechnology, polymer science, and materials. Molecular self-assembly has been attracting increasing interest from the scientific community in the recent years due to its importance in understanding biology and a variety of diseases at the molecular level. In the last few years, considerable advances have been made in the use of peptides as building blocks to produce biological materials for wide range of applications, including fabricating novel supra-molecular structures and scaffolding for tissue repair. Today, the study of biological self-assembly systems represent a significant advance in the molecular engineering and is a rapidly growing scientific and engineering field that crosses the boundaries of existing disciplines. Many self-assembling systems are range from bi-and tri-block copolymers to complex DNA structures as well as simple and complex proteins and peptides. The attractiveness of such bottom-up processes lies in their capability to build uniform, functional units or arrays and the possibility to exploit such structures at meso-and macroscopic scale for life and non-life science applications.

Abstract: Rice Husk Superabsorbent Polymer Composites (RH-SPC) were synthesized through solution polymerization by using Acrylamide (AM) and Acryl Acid (AA) as monomer, Ammonium Persulphate (APS) as initiator and N, N-methylbisacrylamide (MBA) as cross-linker and rice husk (RH) as filler. The amount of rice husk filler and crosslinking agent were varied before the water absorbency (Q) of the prepared RH-SPC were tested by using tea bag method at different pH solution. In this study, the buffer solutions were prepared by the mixing of Hydrochloric Acid (HCl) and Sodium Hydroxide (NaOH). It was found that RH-SPC with the increment of 10 wt% (44.80 g/g) of rice husk filler and 0 wt% (91.40 g/g) of crosslinker results in the highest water absorbency value. Meanwhile, the best pH condition of 10 wt. % of rice husk husk filler and 0 wt% of crosslinker content show the optimum water absorbency at pH 8 and pH 6 with the value of Q are 51.20 g/g and 280.10 g/g, respectively.

Abstract: Hydroxyapatite (HA) has been used extensively in application of biomedical either in the form of porous ceramics, dense ceramics, powders or granules for gap filling or coatings for implants. Synthetic HA also has an excellent ion exchange properties that used as a filling material for chromatography columns. Furthermore, many researchers have reported that high removal efficiency of the heavy metals can be achieved by using synthetic HA. In this study, HA was synthesized via sol-gel method by using calcium nitrate tetrahydrate and triethyl phosphate as the precursors and 2-metoxiethanol ether as an organic solvent. Then, HA sol was deposited on silica-alumina based ceramics whose made by recycled sanitary ware waste by dip-coating method. The obtained coated substrates were then dried at 150°C and subsequently subjected to calcination up to 1000°C. Fourier Transform Infrared (FTIR) characterization for the HA powders dried at 150°C and calcined at 600°C, 800°C and 1000°C were carried out to come out with the spectral characteristic indicative of chemical bonding. High Purity of the obtained hydroxyapatite was confirmed by XRD analysis. The SEM micrographs displayed the microstructure of the HA coatings.