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Faculty of Electronic Engineering & Technology
Country
MY
City
Pauh Putra, Perlis
43 results
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PublicationRemazol orange dye sensitized solar cell( 2017-01-03)
;Siti Salwa Mat Isa ; ; ;Muda M.R. ; ; ; ; ; ;Nur M. SelamatNur Asyikin Mohd AnharWater based Remazol Orange was utilized as the dye sensitizer for dye sensitized solar cell. The annealing temperature of TiO2 working electrode was set at 450 °C. The performance of the device was investigated between dye concentrations of 0.25 mM and 2.5 mM at three different immersion times (3, 12 and 24 hours). The adsorption peak of the dye sensitizer was evaluated using UV-Vis-Nir and the device performance was tested using solar cell simulator. The results show that the performance was increased at higher dye concentration and longer immersion time. The best device performance was obtained at 0.2% for dye concentration of 2.5 mM immersed at 24 hours. -
PublicationEffect of sodium ion addition on copper selenide/chitosan film towards electrical and shielding efficiency improvement( 2024-06)
;Nurul Najiha Mazu ;Hazeem Ikhwan Mazlan ;Josephine Ying Chyi Liew ;Nurul Huda Osman ;Ali ReshakThe operation of electronic devices can be disrupted by unwanted electromagnetic signals, affecting its operation. Deploying electromagnetic shielding is a viable solution to minimize the impact of electromagnetic interference (EMI). The conventional methods of electromagnetic shielding use metal gaskets to safeguard sensitive electronic components, which have drawbacks of cost and weight. Hence, electromagnetic shielding polymer can be an alternative to replace metal gaskets. This work investigates the effect of sodium ion (Na) addition to copper selenide/chitosan (CuSe/Ch) film for electromagnetic shielding applications. The shielding polymers were produced using solution casting methods, while the CuSe was synthesized using the chemical coprecipitation method. Impedance spectroscopy and two port waveguide methods were used to characterize the prepared polymer's electrical properties and shielding efficiency. The results indicate that Na incorporation in the CuSe/Ch film resulted in a 47 % decrease in bulk resistivity and increased DC conductivity from 6.07 × 10-6 S/cm to 3.69 × 10˗5 S/cm. The AC conductivity of films containing Na demonstrates a similar level of conductivity at lower frequencies, followed by a sharp increase at higher frequencies, indicating a more substantial influence of Na at higher frequencies. Higher absorption shielding efficiency (SEA) and lower reflection shielding efficiency (SER) were achieved by introducing Na into the CuSe chitosan film. The Na/CuSe/Ch film shows higher total shielding efficiency at an average of 20 dB, equivalent to 99 % of the EM power shield. -
PublicationSingle wall carbon nanotubes dispersion study of different dye molecules and chitosan( 2017-09-26)
; ;Siti Salwa Mat Isa ;Carbon Nanotubes (CNTs) is known for their hydrophobicity ability. However, this ability can become the bottleneck for the application of CNTs where a highly dispersion of materials are needed. In this project, different dispersing agents were investigated namely dye molecules and chitosan. Three different dyes are studied with different concentration, including 0.05 % of chitosan. The dispersion quality is determined by examining through UV-Vis-NIR. The best dispersion quality investigated here is when the concentration of dye molecules is higher, which is around 2.5 mM. -
PublicationEffect of Ni on the suppression of sn whisker formation in Sn-0.7Cu solder joint( 2021)
; ; ;Andrei Victor Sandu ; ; ;Noor Zaimah Mohd MokhtarJitrin ChaiprapaThe evolution of internal compressive stress from the intermetallic compound (IMC) Cu6Sn5 growth is commonly acknowledged as the key inducement initiating the nucleation and growth of tin (Sn) whisker. This study investigates the effect of Sn-0.7Cu-0.05Ni on the nucleation and growth of Sn whisker under continuous mechanical stress induced. The Sn-0.7Cu-0.05Ni solder joint has a noticeable effect of suppression by diminishing the susceptibility of nucleation and growth of Sn whisker. By using a synchrotron micro X-ray fluorescence (µ-XRF) spectroscopy, it was found that a small amount of Ni alters the microstructure of Cu6Sn5 to form a (Cu,Ni)6Sn5 intermetallic layer. The morphology structure of the (Cu,Ni)6Sn5 interfacial intermetallic layer and Sn whisker growth were investigated by scanning electron microscope (SEM) in secondary and backscattered electron imaging mode, which showed that there is a strong correlation between the formation of Sn whisker and the composition of solder alloy. The thickness of the (Cu,Ni)6Sn5 IMC interfacial layer was relatively thinner and more refined, with a continuous fine scallop-shaped IMC interfacial layer, and consequently enhanced a greater incubation period for the nucleation and growth of the Sn whisker. These verification outcomes proposes a scientifically foundation to mitigate Sn whisker growth in lead-free solder joint. -
PublicationRemazol orange dye sensitized solar cell using graphene oxide and reduced graphene oxide working electrode(Universiti Malaysia Perlis (UniMAP), 2018-12)
; ;Siti S. Mat isa ;N. RosliDye Sensitized Solar Cell (DSSC) is said as a potential solar device which offers easy, cheaper and greener materials and preparation process. However, the efficiency of this device is still an ultimate problem and challenge. In this paper, an organic Remazol orange dye was used as the DSSC dye sensitizer which prepared with different working electrodes. The different working electrodes consist of Titanium Dioxide (TiO2) with Graphene Oxide (GO) and TiO2 with reduced Graphene Oxide (rGO). In order to analyze the adsorption characteristics of GO and rGO, the solution was tested using Ultraviolet-Visible-Near Infrared Spectrophotometry and the surface morphology of all mixed pastes was observed under Atomic Force Microscopy and Scanning Electron Microscope. Then, the device performance was tested under illumination of solar cell simulator. From overall results, the efficiency for all tested devices was quite low from expectation. For this work, the performance of TiO2-rGO DSSC at 0.138% is 84.7% higher compared to the TiO2-GO DSSC which was 0.021%. This result was obtained when the working electrode and dye less exposed to the light during dye preparation process at 24 hours soaking time. -
PublicationAutomated monitoring system for transmission system laboratory modelTransmission System Laboratory Model (TSLM) is a model of power transmission systems use to facilitate the studies of power system. TSLM replicates a power transmission system mimicking the real transmission line. The input and output voltage reading on the current TSLM requires a manual measurement using multimeter. The lack of real time monitoring is rectified in this work. This works propose an automated real time measurement and display system for real time voltage input and output monitoring on the TSLM. An imbedded custom made digital voltmeter and a digital display is used for real time monitoring.
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PublicationrGO-SWCNT hybrid for counter electrode in dye sensitized solar cell(Universiti Malaysia Perlis (UniMAP), 2018-12)
;M. R. Muda ;Siti S. Mat IsaTowards platinum free counter electrode in dye sensitized solar cells, some carbon-based materials like carbon nanotubes and graphene are fully utilized due to their extraordinary properties such as high aspect ratio and conductivity. In this paper, single-walled carbon nanotubes (SWCNT), reduced graphene oxide (rGO) and hybrid structure of rGO-SWCNT spray coated counter electrodes were compared with graphite as the reference material. The morphology of these materials was analyzed with FESEM and FTIR. The DSSC performance was then measured using solar simulator. The current-voltage (I-V) characteristics show that the rGO-SWCNT counter electrode result the excellent performance with efficiency of ~1.86 %, 95.2 % better than graphite. This higher performance was attributed by the complete oxygen-functional group removal during reduction process which offers large active surface area for electro-photocatalytic activity, higher conductivity, better structure and properties compared to the individual forms. -
PublicationEffect of soaking time towards graphitization of empty fruit bunch (EFB) waste(AIP Publishing, 2023)
; ; ; ;Marniati ;Zulfadhli, M. R.M.MutiawatiEmpty fruit bunch (EFB) are the second-highest waste produced in the oil palm industry which is 18 022 tonnes in a year. However, the presence of oil palm waste especially from empty fruit bunch (EFB) give a major problem to the disposal. Herein, EFB waste has been identified as a potential carbon source for synthetic graphite production. This is due to implement the lower heating temperature of synthetic graphite produced in controlled heating conditions. Several parameters have been manipulated to study the effect of various parameters on the graphitization process. Hence, in this study, the effect of soaking time towards graphitization of empty fruit bunch (EFB) waste has been investigated. EFB waste was heat treated with various soaking times which is 2 hours, 2.5 hours and 3 hours in controlled heating conditions with constant heating temperature at 500°C and heating rate at 10°/minute After heating treatment, the samples were characterized using X-ray Diffraction (XRD) and analyzed by X'Pert Highscore Plus software. The functional group of synthetic graphite was determined by using Fourier Transform Infrared spectroscopy (FTIR). The morphological study was carried out by using Scanning Electron Microscope (SEM). From the analysis, the best synthetic graphite produced is at the 2.5 hours soaking time with a constant heating temperature at 500°C and a constant heating rate at 10°/min. -
PublicationGraphitization of empty fruit bunch (EFB) waste at lower heating temperature(AIP Publishing, 2023)
; ; ; ;Marniati ;Desita Ria YusianMuhammad Zulfadhly Mohd FazilPreviously, synthetic graphite was produced at higher heating temperature, which is above 2500°C in complex processing method and by using petroleum coke, anthracite, and coal tar pitch as the starting materials. These materials are known as non-waste sources. Therefore, in this study, Empty Fruit Bunch Waste (EFB) has been identified as a potential carbon source from waste to replace the non-waste sources of starting materials for synthetic graphite production. Hence, by implementing a controlled heating condition via pyrolysis process, with fixed heating rate and soaking time, Empty Fruit Bunch Waste (EFB), was heated at 3 different series of heating temperatures, which are, 300°C, 400°C and 500°C. The heating rate applied was maintained at 10°/min and the soaking time used 3 hours. After the heating treatment, the synthetic graphite obtained was characterized by various analytical tools, including, X-Ray Diffraction (XRD) analysis, Scanning Electron Microscope (SEM) analysis, and Fourier Transform Infra-Red (FTIR) Analysis. Based on the analysis, it was confirmed that synthetic graphite was successfully synthesized by heat treatment at 500 °C with 10°/min of heating rate and 3 hours soaking time. Synthetic graphite was observed in the form of amorphous carbon based on the XRD diffraction pattern that matches with the reference code of 00-041-1487. -
PublicationCharacterization of doped ZnO thin film for Ammonia gas sensing application(Institute of Physics, Polish Academy of Sciences, 2023)
; ;Fatin Amira Hasbullah ;Anis Syafiqa Rosman ; ; ; ;Nurul Huda Osman ;D. Darminto ;Ali Hussain ReshakSebastian GarusThis paper reports on the characterization of Sn- and Al-doped zinc oxide thin film for potential ammonia gas detection. The sol–gel method has been used to deposit the dopant onto the glass substrate at an annealing temperature of 500◦C for three different doping concentrations, which are 0.5, 1.0, and 1.5 at.%. The method used to produce this thin film is sol–gel, as it is cheap, easy, and can be employed at low temperatures. The studies involve the investigation of the morphological structures and electrical and optical properties of doped ZnO. In terms of structural properties, scanning electron microscope images of Sn- and Al-doped ZnO change as the dopant concentration is increased. The doped thin film response and recovery towards 200 ppm of ammonia were observed and recorded. Both dopants show good gas sensing response. The recorded resistance reading suggests that Al is the superior dopant in gas sensing as it produces a low resistance reading of 230 Ω as opposed to 140 kΩ produced by Sn-doped ZnO thin film.