Pusat Pengajian Sains Fizik - Tesis
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- PublicationLow-Cost Surface Passivation For Black Silicon Solar Cells By Liquid Phase Deposition Techniques(2023-12)Ahmad, Sheriff MuhiddinBlack silicon (b-Si) is a promising surface structure for solar cells due to its low broadband reflectance and superior light trapping properties within the 300–1100 nm wavelength region. For the fabrication of b-Si, one-step electroless metal-assisted chemical etching (MACE) is employed which produces nanowires (NWs) with heights of about 0.4 – 0.8 μm that result in low broadband reflectance but leads to high surface recombination in b-Si solar cells. To address this issue, efficient surface passivation is inevitable, which is essential for developing high-efficiency b-Si solar cells. Surface passivation by the formation of thermal silicon dioxide (SiO2) is the conventional method that involves high-temperature processing. The high process temperatures could deteriorate the nanotextured b-Si formed by the etching process, compromising broadband light absorption in the solar cells. Therefore, liquid phase deposition (LPD) is a promising alternative surface passivation technique that can reduce the surface recombination issue.
- PublicationMolecular Dynamics Simulation Of Nano Wetting Of Lennard-Jones Droplet On Curved Surfaces(2023-12)Alhiassah, Saleh Irsheid SalehThis thesis aims to investigate the wetting behavior of LJ nanodroplets on curved surfaces using molecular dynamics (MD) simulations implemented in the Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) package. The proposed methodology does not suffer the technical issues that plague experimental approaches. The thesis focuses on the influence of curved surface geometry and varying LJ interaction potentials on wetting transitions.
- PublicationInvestigation Of Zinc Oxide Quantum Dots Based Thin Films On Flexible Substrate For Perovskite Solar Cells(2023-12)Sani, MuhammadIn this research, ZQDs is synthesized via a cost-effective and solution- processed precipitation technique at low temperature (60-150 o C). The as-prepared colloidal ZQDs solution was spin-coated onto flexible Polyethelene terephthalate (PET) and indium-doped tin oxide coated Polyethelene terephthalate (ITO/PET) substrates. Tuning the optical and electrical properties of ZQDs films through changing experimental parameters without any doping has been reported. The influence of film thickness and ZQDs solution concentration (ZQC) on the structural, surface, compositional, optical and electrical properties of the spin-coated thin films and their effects on the FPKSCs performance were investigated.
- PublicationPedot:Pss Polymer-Based Heterojunction Emitter For Textured Monocrystalline Silicon Solar Cells(2024-01)Rosle, Mohamad Aliff AsraffThis work investigates optical, surface morphological and electrical properties of p-type PEDOT:PSS emitter on n-type textured mono c-Si for solar cell application. The mono c-Si wafers are textured using sodium hydroxide (NaOH) solution to form random upright pyramids on the surface. The parameter change involves concentration of NaOH (1%-3%), texturing temperature (70oC-90oC) and texturing time (40 min-60 min). The best sample is 2% NaOH for 50 min at 80oC, which results in weighted average reflection (WAR) of 18.06%.
- PublicationUltrasound Assisted Bismuth Coated Iron Oxide Nanoparticles For A Potential Dual-Modal Ct/Mr Imaging Contrast Media(2024-02)Braim, Farhank SaberIn this study, ultrasound rapidly modified Fe3O4 NPs by coating their surface with Bi NPs, creating unique Fe3O4@Bi composite NPs for computed tomography (CT) scan and magnetic resonance imaging (MRI).