Voon Chun Hong
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Preferred name
Voon Chun Hong
Official Name
Hong, Voon Chun
Alternative Name
Voon, C. H.
Voon, Chun Hong
Hong, Voon Chun
Hong, V. C.
Main Affiliation
Scopus Author ID
55334719400
Researcher ID
D-2050-2015

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Now showing 1 - 10 of 47
  • Publication
    Sustainable production of graphene oxide with ascorbic acid reduction characterization and insights
    ( 2024-10)
    Thaddeus Lee
    ;
    Chun Hui Tan
    ;
    Chai Yan Ng
    ;
    Foo Wah Low
    ;
    Hing Wah Lee
    ;
    Voon Chun Hong
    In this study, graphene oxide (GO) was synthesized from graphite powder using KMnO4 and a concentrated mixture of H2SO4/H3PO4. The obtained GO was subsequently reduced using ascorbic acid. The ratios of H2SO4 to H3PO4 and KMnO4 to graphite powder were kept constant. The synthesized GO and reduced graphene oxide (rGO) were evaluated using UV-visible spectroscopy, FT-IR spectroscopy, XRD, SEM, and EDX. The findings showed that processing graphite powder with KMnO4 at 60 °C for 12 hours resulted in a high degree of oxidation and minimal defects. Furthermore, ascorbic acid, an alternative to highly toxic hydrazine, aided in eliminating oxygen-containing functional groups in the rGO. This study focuses on the properties of GO produced using the improved Hummer's method, and the changes observed after chemical reduction.
  • Publication
    Potentials of MicroRNA in Early Detection of Ovarian Cancer by Analytical Electrical Biosensors
    ( 2022-01-01)
    Nor Azizah Parmin
    ;
    Uda Hashim
    ;
    Subash Chandra Bose Gopinath
    ;
    Nadzirah S.
    ;
    Salimi M.N.
    ;
    Voon Chun Hong
    ;
    Muhammad Nur Aiman Uda
    ;
    Muhammad Nur Afnan Uda
    ;
    Rozi S.K.M.
    ;
    Rejali Z.
    ;
    Afzan A.
    ;
    Azan M.I.A.
    ;
    Yaakub A.R.W.
    ;
    Hamzah A.A.
    ;
    Dee C.F.
    The importance of nanotechnology in medical applications especially with biomedical sensing devices is undoubted. Several medical diagnostics have been developed by taking the advantage of nanomaterials, especially with electrical biosensors. Biosensors have been predominantly used for the quantification of different clinical biomarkers toward detection, screening, and follow-up the treatment. At present, ovarian cancer is one of the severe complications that cannot be identified until it becomes most dangerous as the advanced stage. Based on the American Cancer Society, 20% of cases involved in the detection of ovarian cancer are diagnosed at an early stage and 80% diagnosed at the later stages. The patient just has a common digestive problem and stomach ache as early symptoms and people used to ignore these symptoms. Micro ribonucleic acid (miRNA) is classified as small non-coding RNAs, their expressions change due to the association of cancer development and progression. This article reviews and discusses on the currently available strategies for the early detection of ovarian cancers using miRNA as a biomarker associated with electrical biosensors. A unique miRNA-based biomarker detections are specially highlighted with biosensor platforms to diagnose ovarian cancer.
  • Publication
    Zinc oxide/graphene nanocomposite as efficient photoelectrode in dye-sensitized solar cells: Recent advances and future outlook
    ( 2022-05-01)
    Mahalingam S.
    ;
    Low F.W.
    ;
    Omar A.
    ;
    Manap A.
    ;
    Rahim N.A.
    ;
    Tan C.H.
    ;
    Abdullah H.
    ;
    Voon Chun Hong
    ;
    Rokhmat M.
    ;
    Wibowo E.
    ;
    Oon C.S.
    Dye-Sensitized Solar Cells (DSSCs), also known as Grätzel cells, are a third-generation photovoltaic technology that has garnered extensive interest due to its simplicity of fabrication, economical, and relatively high power conversion efficiency (PCE). The PCE of the photovoltaic cells is primarily related to the architecture of the cells, as well as the electrodes and electrolyte employed. Using zinc oxide (ZnO) coupled with two-dimensional graphene as photoelectrode enables efficient charge transfer and minimizes electron–hole recombination in the DSSCs, resulting in improved performance. This review outlines the feasibility and performance enhancement of ZnO/graphene nanocomposite and its derivatives as photoelectrode for DSSCs. The structural features, optical properties, electron transport, and dye interaction of the ZnO/graphene nanocomposite-based photoelectrode were considered in this review. In addition, the limitations of ZnO/graphene derivatives as photoelectrodes and their solutions were extensively discussed, as well as their prospects. The ZnO/graphene-based photovoltaic cells exhibit an efficiency of up to 11.5% under different dyes and electrolytes. The recent progress achieved with this photoelectrode, which is a viable substitute for titanium dioxide (TiO2), is also thoroughly reviewed.
  • Publication
    Voltammetric DNA Biosensor for Human Papillomavirus (HPV) Strain 18 Detection
    ( 2020-07-09)
    Mhd Akhir M.A.
    ;
    Nor Azizah Parmin
    ;
    Uda Hashim
    ;
    Subash Chandra Bose Gopinath
    ;
    Rejali Z.
    ;
    Afzan A.
    ;
    Muhammad Nur Aiman Uda
    ;
    Muhammad Nur Afnan Uda
    ;
    Voon Chun Hong
    This research was developed to focus on the study of the voltammetric DNA biosensor for the detection of HPV strain 18. In this research, electrical DNA biosensor was expected to detect HPV strain 18 more efficiently by using electrical characterization. In this project, device inspection was conducted to make sure the functional of the gold interdigitated electrode (IDE) by using Scanning Electron Microscope (SEM). 3-Aminopropyl Triethoxysilane (APTES) solution was used for the process of surface modification to form the amine group on the surface of the device to facilitate the attachment of the DNA probe. In this project, synthetic DNA sample and DNA from the saliva of several Biosystems Engineering students were used as the target DNA. The current-voltage (I-V) electrical characterization was conducted to detect the presence of HPV strain 18 in both DNA samples. As the results, perfect alignment between the electrodes on the IDE was detected under SEM. Surface modification of the biosensor successfully conducted which is the covalent bond between APTES and DNA probe increase the electrical. Synthetic DNA shows the presence of HPV strain 18 while there was no HPV strain 18 detected in the DNA from saliva samples.
  • Publication
    Heat transfer improvement in simulated small battery compartment using metal oxide (CuO)/deionized water nanofluid
    ( 2020-02-01)
    Bin-Abdun N.A.
    ;
    Zuradzman Mohamad Razlan
    ;
    Shahriman Abu Bakar
    ;
    Voon Chun Hong
    ;
    Ibrahim Z.
    ;
    Wan Khairunizam Wan Ahmad
    ;
    Mohd Ridzuan Mohd Jamir
    Improving the heat transfer coefficient of working fluids is essential for achieving the best performance of manufacturing systems. As a replacement of conventional working fluids, nanofluids have a high potential for improving this heat transfer coefficient. However, nanofluids are seldom implemented in actual systems, and several factors should be considered before actual application. Accordingly, this study investigated the thermophysical properties and heat transfer rate of CuO/deionized water nanofluid with and without sodium dodecyl sulfate (SDS) surfactants. Three different volumetric concentrations of the nanofluid were prepared using a two-step preparation method. The experimental steps were divided into two phases: static and dynamic. In these experiments, the thermophysical properties of the prepared nanofluids and the heat transfer coefficient were measured using an apparatus designed based on an actual heat exchanger for a lithium ion polymer battery compartment. The effects of flow rate and surfactants on the heat transfer rate of the nanofluids with varying volumetric concentrations of 0.08%, 0.16%, and 0.40% were analyzed. The results indicate that the heat transfer rate increases considerably as the flow rate increases from 0.5 L/min to 1.2 L/min and with the presence of surfactants. The highest heat transfer rate was obtained at a 0.40% volumetric concentration of CuO/deionized water nanofluid with SDS surfactant.
  • Publication
    Effect of solvent on mechanical and physical properties of PMMA/Sic composite films
    ( 2024-12)
    Auni Fakhira Che Baharudin
    ;
    Lim Bee Ying
    ;
    Voon Chun Hong
    ;
    Teh Pei Leng
    ;
    Tan Soo Jin
    The selection of solvent in solution casting is crucial as it may affect the morphology and properties of the resulting composite films. In this study, the effect of solvent on the properties of poly(methyl methacrylate)/silicon carbide (PMMA/SiC) composite films was investigated. By using acetone, the solution casting was carried out at various solvent-to-solid (S/S) ratio, from 4:1 to 10:1 at room temperature. It was found that the increasing S/S ratio enhanced the tensile strength and modulus of elasticity of pristine PMMA films but deteriorated its elongation at break, up to 8:1 ratio. The crystallinity of the PMMA films was found to increase with S/S ratio, as confirmed by the higher peak intensity in X-Ray Diffraction (XRD) patterns and the SEM micrographs. In the second part of the study, by using S/S ratio of 8:1, the nano sized SiC (0.25 wt%) was added as a filler into PMMA and toluene with different ratio was added as a secondary solvent. The addition of SiC has increased the tensile strength and modulus of elasticity of PMMA/SiC but decreased its elongation at break. However, the presence of toluene reduced the tensile strength of the PMMA/SiC composite films and resulting in rougher tensile fracture surfaces as shown in SEM micrographs. The toluene with nonpolar nature had affected the distribution of SiC in PMMA. It can be concluded that the properties of the PMMA composites films can be tailored according to the needs of applications.
  • Publication
    Effect of Microwave Power and Clamping Pressure on the Microwave Welding of Polypropylene Using Silicon Carbide Nanowhiskers as Microwave Susceptor
    ( 2022-01-01)
    Foong P.Y.
    ;
    Voon Chun Hong
    ;
    Lim B.Y.
    ;
    Teh P.L.
    ;
    Mohd Afendi Rojan
    ;
    Nor Azizah Parmin
    ;
    Subash Chandra Bose Gopinath
    ;
    Mohd Khairuddin Md Arshad
    ;
    Low F.W.
    ;
    Mahalingam S.
    ;
    Manap A.
    ;
    Ruslinda A. Rahim
    ;
    Uda Hashim
    Due to their excellent dielectric properties and the rapid response to microwave irradiation, silicon carbide nanowhiskers (SiCNWs) were employed as microwave susceptor in this study to absorb microwave and locally melt the surrounding polypropylene (PP) substrates for the joining of PP substrates. Complete welded joint is formed after the melted PP was cooled and resolidified. Other than microwave susceptor, SiCNWs also acted as the nanofillers in strengthening the welded joint through the formation of SiCNWs reinforced PP nanocomposite at the interface of PP substrates. Besides, the effect of microwave power on the microwave welding of PP substrates using SiCNWs as susceptor was studied and reported. It was found that the tensile strength and modulus of elasticity of the welded joint improved as microwave power increased. However, it deteriorates the flexibility of the welded joint as high stiffness SiCNWs were incorporated deeper into the PP matrix which restricted the PP chain mobility. Aside from microwave power, clamping pressure is also critical in determining the mechanical properties of a welded joint. When compared to unclamped welded joint, the tensile strength, modulus of elasticity and flexibility of welded joint subjected to clamping pressure improved drastically. Moreover, the tensile strength of welded joint increased when the clamping pressure was increased from P1 to P3, but decreased when the clamping pressure was further increased to P4 due to the occurrence of flashing at welded joint. The formation mechanism of SiCNWs reinforced PP welded joint was also proposed in this study. Compared to conventional welding, this welding process is easy, straightforward and is able to produce welded joint with outstanding mechanical properties via precise controlling of the processing parameters. Thus, microwave welding is thought to offer an option for the joining of thermoplastics and other applications.
  • Publication
    Functionalized carbon black in epoxy composites: effect of single- and dual-matrix systems
    ( 2022-07-01)
    Phua J.L.
    ;
    Teh Pei Leng
    ;
    Yeoh C.K.
    ;
    Voon Chun Hong
    Functionalized carbon black (CB) using three different surface modification methods: wet oxidation, epoxy monomer impregnation, and air oxidation, in single-epoxy composites and dual-matrix epoxy/poly(methyl methacrylate) PMMA composites at 15 vol% of CB content was studied in this research. The characterization on the surface modification CB was done via Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller (BET), and thermal gravimetric analysis. The phenol or ether, carboxylic acid, and epoxide functional groups were found on CB after surface modifications, along with a change in structure and BET surface area. Thermal degradation of CB was different after surface modification. This study further investigated the effect of the addition of surface-modified CB into epoxy resin, where the state of dispersion and distribution was observed under scanning electron microscopy. After surface modification, the mechanical testing via flexural and fracture toughness was done, where improvement was observed. A minor decrease in the electrical bulk conductivity of the composites was measured, which was due to a reduction in the degree of agglomeration. Both the thermal stability and CTE of surface-modified CB-filled epoxy composites show a decrement. Graphic abstract: Chemical modification of CB using air oxidation, wet oxidation, and epoxy monomer impregnation methods.[Figure not available: see fulltext.]
  • Publication
    Gold-Nanohybrid Biosensors for Analyzing Blood Circulating Clinical Biomacromolecules: Current Trend toward Future Remote Digital Monitoring
    ( 2022-01-01)
    Letchumanan I.
    ;
    Subash Chandra Bose Gopinath
    ;
    Mohd Khairuddin Md Arshad
    ;
    Mohamed Saheed M.S.
    ;
    Perumal V.
    ;
    Voon Chun Hong
    ;
    Uda Hashim
    Mortality level is worsening the situation worldwide thru blood diseases and greatly jeopardizes the human health with poor diagnostics. Due to the lack of successful generation of early diagnosis, the survival rate is currently lower. To overcome the present hurdle, new diagnostic methods have been choreographed for blood disease biomarkers analyses with the conjunction of ultra-small ideal gold nanohybrids. Gold-hybrids hold varieties of unique features, such as high biocompatibility, increased surface-to-volume ratio, less-toxicity, ease in electron transfer and have a greater localized surface plasmon resonance. Gold-nanocomposites can be physically hybrid on the sensor surface and functionalize with the biomolecules using appropriate chemical conjugations. Revolutionizing biosensor platform can be prominently linked for the nanocomposite applications in the current research on medical diagnosis. This review encloses the new developments in diagnosing blood biomarkers by utilizing the gold-nanohybrids. Further, the current state-of-the-art and the future envision with digital monitoring for facile telediagnosis were narrated.
  • Publication
    Fabrication of Integrated Electrode for pH Sensor Application
    ( 2021-01-01)
    Mohd Akhir F.S.
    ;
    Foo Kai Loong
    ;
    Jin T.S.
    ;
    Uda Hashim
    ;
    Voon Chun Hong
    ;
    Azman Abu Hassan M.
    Integrated Electrode (IDEs), as a sensor, is a pervasive device in modern electronics and future hopes for producing a highly sensitive and selective sensor. In this work, a simple method of conventional photolithography for the fabrication of interdigitated electrodes is presented in detail. The structural of highly uniform IDEs device was optically characterized using high power microscope (HPM) and scanning electron microscope (SEM). Besides, the fabricated IDEs device was undergone electrical measurement with different pH. The result shows the highest current at 96 nA when the IDEs was tested with pH 10. Overall, our study establishes a correlation between structural and electrical properties of Al IDEs thin films with different pH