Faculty of Electronic Engineering & Technology
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MY
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Pauh Putra, Perlis

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Now showing 1 - 10 of 47
  • Publication
    Remazol orange dye sensitized solar cell
    ( 2017-01-03)
    Siti Salwa Mat Isa
    ;
    Muhammad Mahyiddin Ramli
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Muda M.R.
    ;
    Shahrir Rizal Kasjoo
    ;
    Muammar Mohamad Isa
    ;
    Nurul Izza Mohd Nor
    ;
    Norhawati Ahmad
    ;
    Nazuhusna Khalid
    ;
    Nur M. Selamat
    ;
    Nur Asyikin Mohd Anhar
    Water 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.
  • Publication
    Effect 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
    ;
    Muhammad Mahyiddin Ramli
    ;
    Ali Reshak
    The 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.
  • Publication
    Single wall carbon nanotubes dispersion study of different dye molecules and chitosan
    ( 2017-09-26)
    Muhammad Mahyiddin Ramli
    ;
    Siti Salwa Mat Isa
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Sohiful Anuar Zainol Murad
    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.
  • Publication
    Effect of soaking time towards graphitization of empty fruit bunch (EFB) waste
    (AIP Publishing, 2023)
    Norizah Abd Karim
    ;
    Che Mohd Ruzaidi Ghazali
    ;
    Muhammad Mahyiddin Ramli
    ;
    Marniati
    ;
    Zulfadhli, M. R.M.
    ;
    Mutiawati
    Empty 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.
  • Publication
    Characterization of doped ZnO thin film for Ammonia gas sensing application
    (Institute of Physics, Polish Academy of Sciences, 2023)
    Shazlina Johari
    ;
    Fatin Amira Hasbullah
    ;
    Anis Syafiqa Rosman
    ;
    Muhammad Mahyiddin Ramli
    ;
    Mohd Fairus Ahmad
    ;
    Norizah Abd Karim
    ;
    Nurul Huda Osman
    ;
    D. Darminto
    ;
    Ali Hussain Reshak
    ;
    Sebastian Garus
    This 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.
  • Publication
    Semiconducting biomass-based amorphous carbon films and their potential application in photovoltaic devices
    (Elsevier Ltd, 2025)
    Endhah Purwandari
    ;
    Retno Asih
    ;
    Sudarsono
    ;
    Diky Anggoro
    ;
    Gerald Ensang Timuda
    ;
    Malik Anjelh Baqiya
    ;
    Iman Santoso
    ;
    Hideki Nakajima
    ;
    Muhammad Mahyiddin Ramli
    ;
    Agus Subekti
    ;
    Darminto
    Amorphous carbon (aC) is highly appealing because of its unique structure, electrical and optical properties, making it appropriate for various applications, especially in energy conversion. This work presents a comprehensive study on the synthesis of aC materials, including both intrinsic (i-type) and doped conditions (p- and n-type), to enhance the performance of photovoltaic films. Carbon materials are derived from biomass using a straightforward and environmentally conscious technique. The obtained carbon compound demonstrates an amorphous state with a substantial prevalence of the sp2 C=C component. Raman spectroscopy and electron microscopy confirmed the stacking of 2D layers forming a multilayer graphene structure. The carbon compound prepared AC films deposited onto a quartz glass surface via spray coating. The films have a thickness ranging from 247 to 478 nm. The dielectric constants of the optical parameters reveal resonant exciton features at a photon energy of ∼3.8 eV, whereas the real component exhibits semiconductive properties. The refractive indices of the p-, i-, and n-layers, which have gap energies in decreasing order, demonstrate a decline. The optical conductivity of aC is higher than that of amorphous silicon, specifically 0.54 × 103Ω−1cm−1, 0.48 × 103 Ω−1cm−1, and 0.53 × 103 Ω−1cm−1 for the p-, i-, and n-type films, respectively. Based on this outcome, it is reasonable to suggest that the recently developed material is potentially important as a photovoltaic device.
  • Publication
    Remazol orange dye sensitized solar cell using graphene oxide and reduced graphene oxide working electrode
    (Universiti Malaysia Perlis (UniMAP), 2018-12)
    Norhayati Sabani
    ;
    Siti S. Mat isa
    ;
    Muhammad Mahyiddin Ramli
    ;
    N. Rosli
    Dye 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.
      1  21
  • Publication
    Physical, mechanical and electrical properties of Chitosan/Graphene Oxide composite films for Copper Ions (Cu²+) detection
    (Springer, 2023)
    Mohammad Abdull Halim Mohd Abdull Majid
    ;
    Nurul Huda Osman
    ;
    Nizam Tamchek
    ;
    Nurul Asyikin Ahmad Sukri
    ;
    Hazeem Ikhwan Mazlan
    ;
    Nurul Najiha Mazu
    ;
    Adilah Idris
    ;
    Josephine Ying Chyi Liew
    ;
    Muhammad Mahyiddin Ramli
    Copper ions are one of the metal ions that contribute significantly to water pollution and threaten the ecosystem. The threat heightened the importance of the detection and removal of the contaminants. In this study, the Chitosan/Graphene Oxide (CH/GO) composite film was synthesized at different GO ratios via a direct casting technique. The structural, mechanical and film adsorption capacities were characterized along with the electrical properties. The results revealed that adding GO into CH at a 1:5 ratio produces the highest strength and adsorption capacity. The 1:5 film was then tested for its electrical properties to see the possibility of utilizing it as part of an electrical measurement system. Various electrical parameters such as permittivity (ε′, ε″), Tanδ, bulk resistivity (Rb) and DC conductivity (σDC) were studied. Results show that the 1:5 ratio chitosan film in various Cu²+ concentrations yielded significant differences in electrical properties. The Rb and σDC gave the most significant results and can be used as Cu²+ detection parameters.
      2  21
  • Publication
    The Effect of GO/TiO2 Thin Film During Photodegradation of Methylene Blue Dye
    ( 2021)
    Azliza Azani
    ;
    Dewi Suriyani Che Halin
    ;
    Mohd. Mustafa Al Bakri Abdullah
    ;
    Kamrosni Abdul Razak
    ;
    Mohd Fairul Sharin Abdul Razak
    ;
    V Chobpattana
    ;
    Mohd Arif Anuar Mohd Salleh
    ;
    Muhammad Mahyiddin Ramli
    Titanium (IV) isopropoxide (TTIP) was used to synthesize GO/TiO2 thin films using a sol-gel spin-coating method onto a glass substrate, undergoing an heat tretment at 350 °C. Several amounts of graphene oxide (GO) (0-20mg) were weighed into a sol solution of TiO2 to produce GO/TiO2 thin films. The thin film samples were characterized by X-ray diffraction (XRD) to analyze the samples’ phase and by scanning electron microscopy (SEM) to analyze the samples’ microstructure. Physical testing such as water contact angle (WCA) was analyzed using an optical microscope with J-Image software. In contrast, the optical band gap and photodegradation of methylene blue under sunlight irradiation of the thin film was analyzed using UV-VIS spectrophotometry. GO5 thin film sample showed low-intensity anatase phase formation, where the microstructure revealed a larger surface area with the addition of GO. WCA reveals that GO/TiO2 thin film exhibits super hydrophilic properties where the angle decreases from 37.83° to 4.11°. The optical result shows that GO has improved the absorption edges by expanding into visible regions. Moreover, due to the existence of GO 3.30 eV band gap energy of TiO2 decreases from to 3.18 eV obtained by GO5. The improved adsorption edge allows Ti3+, O2 and interstitial states to be formed in low valence states with energy underneath than in the TiO2 band gap. Therefore, the photodegradation of methylene blue (MB) dye increases from 48 % to 59 % in the GO/TiO2 thin film.
      1  66
  • Publication
    Characterization of Excimer Laser Micromachining Parameters to Derive Optimal Performance for the Production of Polydimethylsiloxane (PDMS)-based Microfluidic Devices
    ( 2024-01-01)
    Shazlina Johari
    ;
    Ting Z.K.
    ;
    Mazlee Mazalan
    ;
    Yufridin Wahab
    ;
    Anas Mohd Noor
    ;
    Mohd Fairus Ahmad
    ;
    Muhammad Mahyiddin Ramli
    Laser micromachining has been used as an alternative to producing microfluidics structures and simplifying the conventional soft lithography process. In this paper we characterize the excimer laser micromachining parameters and demonstrate its application by producing several microfluidic structures in polydimethylsiloxane (PDMS). The parameters include the number of laser pulses, laser energy and rectangular variable aperture (RVA) in both x- and y-directions. We found that the laser energy and pulse rate affect the depth of micromachining d channels, while RVA in both x- and y-directions affects the width of the channels. Repetition of laser scan does not change the channel width but significantly changes the channel depth. Proper adjustment for laser energy and pulse rate is required to fabricate a desired channels depth. In order to demonstrate the microfabrication capability of an excimer laser with the optimal operating parameters, several microfluidic structures were micromachining d into PDMS with a KrF excimer laser.
      1