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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  • Publication
    Effect of manganese content on the fabrication of porous anodic alumina
    ( 2012)
    Voon Chun Hong
    ;
    M. N. Derman
    ;
    Uda Hashim
    The influence of manganese content on the formation of well-ordered porous anodic alumina was studied. Porous anodic alumina has been produced on aluminium substrate of different manganese content by single-step anodizing at 50 V in 0.3 M oxalic acid at 15°C for 60 minutes. The well-ordered pore and cell structure was revealed by subjecting the porous anodic alumina to oxide dissolution treatment in a mixture of chromic acid and phosphoric acid. It was found that the manganese content above 1 wt% impaired the regularity of the cell and pore structure significantly, which can be attributed to the presence of secondary phases in the starting material with manganese content above 1 wt%. The pore diameter and interpore distance decreased with the addition of manganese into the substrates. The time variation of current density and the thickness of porous anodic alumina also decreased as a function of the manganese content in the substrates.
  • Publication
    Effective synthesis of silicon carbide nanotubes by microwave heating of blended silicon dioxide and multi-walled carbon nanotube
    ( 2017)
    Voo Chung Sung Tony
    ;
    Voon Chun Hong
    ;
    Lee Chang Chuan
    ;
    Lim Bee Ying
    ;
    Subash Chandra Bose Gopinath
    ;
    Foo Kai Loong
    ;
    Mohd Khairuddin Md Arshad
    ;
    Ruslinda A. Rahim
    ;
    Uda Hashim
    ;
    Nashaain Mohd Nordin
    ;
    Yarub Al-Douri
    Silicon carbide nanotube (SiCNTs) has been proven as a suitable material for wide applications in high power, elevated temperature and harsh environment. For the first time, we reported in this article an effective synthesis of SiCNTs by microwave heating of SiO2 and MWCNTs in molar ratio of 1:1, 1:3, 1:5 and 1:7. Blend of SiO2 and MWCNTs in the molar ratio of 1:3 was proven to be the most suitable for the high yield synthesis of β-SiCNTs as confirmed by X-ray diffraction pattern. Only SiCNTs were observed from the blend of MWCNTs and SiO2 in the molar ratio of 1:3 from field emission scanning electron microscopy imaging. High magnification transmission electron microscopy showed that tubular structure of MWCNT was preserved with the inter-planar spacing of 0.25 nm. Absorption bands of Si-C bond were detected at 803 cm-1 in Fourier transform infrared spectrum. Thermal gravimetric analysis revealed that SiCNTs from ratio of 1:3 showed the lowest weight loss. Thus, our synthetic process indicates high yield conversion of SiO2 and MWCNTs to SiCNTs was achieved for blend of SiO2 and MWCNTs in molar ratio of 1:3.
  • Publication
    Effect of temperature of oxalic acid on the fabrication of porous anodic alumina from A1-Mn alloys
    ( 2013-04-12)
    Voon Chun Hong
    ;
    Mohd Nazree Derman
    ;
    Uda Hashim
    ;
    K. R. Ahmad
    ;
    Foo Kai Loong
    The influence of temperature of oxalic acid on the formation of well-ordered porous anodic alumina on Al-0.5 wt% Mn alloys was studied. Porous anodic alumina has been produced on Al-0.5 wt% Mn substrate by single-step anodising at 50 V in 0.5 M oxalic acid at temperature ranged from 5°C to 25°C for 60 minutes. The steady-state current density increased accordingly with the temperature of oxalic acid. Hexagonal pore arrangement was formed on porous anodic alumina that was formed in oxalic acid of 5, 10 and 15°C while disordered porous anodic alumina was formed in oxalic acid of 20 and 25°C. The temperature of oxalic acid did not affect the pore diameter and interpore distance of porous anodic alumina. Both rate of increase of thickness and oxide mass increased steadily with increasing temperature of oxalic acid, but the current efficiency decreased as the temperature of oxalic acid increased due to enhanced oxide dissolution from pore wall.
  • Publication
    Dielectric properties and microwave absorbing properties of silicon carbide nanoparticles and silicon carbide nanowhiskers
    ( 2023-04)
    Phey Yee Foong
    ;
    Voon Chun Hong
    ;
    Lim Bee Ying
    ;
    Teh Pei Leng
    ;
    Mohd Afendi Rojan
    ;
    Subash Chandra Bose Gopinath
    ;
    Nor Azizah Parmin
    ;
    Mohd Khairuddin Md Arshad
    ;
    Yeng Seng Lee
    ;
    Ruslinda A. Rahim
    ;
    Uda Hashim
    Silicon carbide (SiC) is well known for their outstanding microwave absorbing properties. SiC nanomaterials (SiCNMs) are expected to have better microwave absorption performance due to their high specific surface area. To date, no study was reported to compare the dielectric properties and microwave absorbing properties of different type of SiCNMs. Therefore, the objective of this paper is to compare the dielectric properties and microwave absorption properties of different types of SiCNMs. In this paper, SiC nanoparticles (SiCNPs) and SiC nanowhiskers (SiCNWs) were characterised using SEM and XRD. In addition, their dielectric properties and microwave absorbing properties were measured using network analyser and transmission line theory. It was found that SiCNWs achieved higher dielectric constant and loss factor which are and εr’ =17.94 and εr″ = 2.64 compared to SiCNPs that only achieved εr’ = 2.83 and εr″ = 0.71. For microwave absorbing properties, SiCNWs and SiCNPs attained minimum reflection loss of -10.41 dB and -6.83 dB at 5.68 GHz and 17.68 GHz, respectively. The minimum reflection loss of SiCNPs and SiCNWs obtained in this study is much lower than the nanometer-SiC reported previously. These results suggested that SiCNWs can be an ideal candidate of microwave susceptors for various microwave applications
  • Publication
    Facile electrical DNA genosensor for human papillomavirus (HPV 58) for early detection of cervical cancer
    ( 2023-07)
    F. Nadhirah Jaapar
    ;
    Nor Azizah Parmin
    ;
    Nur Hamidah Abdul Halim
    ;
    Uda Hashim
    ;
    Subash Chandra Bose Gopinath
    ;
    Ruslinda A. Rahim
    ;
    Sh. Nadzirah
    ;
    Voon Chun Hong
    ;
    Muhammad Nur Aiman Uda
    ;
    Wei Chern Ang
    ;
    Iffah Izzati Zakaria
    ;
    Zulida Rejali
    ;
    Amilia Afzan
    ;
    Azrul Azlan Hamzah
    ;
    Chang Fu Dee
    ;
    F. Syakirah Halim
    For decades, a Pap smear test has been applied as a conventional method in detecting Human Papillomavirus caused cervical cancer. False-positive results were also recorded while using it as conventional method. Current biosensor such as Hybrid (II) Capture resulted in higher time consumption and cost. s Meanwhile, in this study we provided facile, mini, rapid, highly sensitive, eco-friendly, and cost-effective sensing system focusing on HPV strain 58 (HPV58) in a nano-size lab-on-chip technology genosensor. 30-mer of virus ssDNA designed and analyzed as a probe via bioinformatics tools such as GenBank, Basic Local Alignment Searching Tools (BLAST) and ClustalW. Nanotechnology-developed colloidal Gold-nanoparticles (AuNPs) are used in the biosensor fabrication to produce high stability and electron efficient transmission during electrical measurement. AuNPs-APTES modified on active sites of IDEs, followed by immobilization of specific probe ssDNA for HPV 58. Hydrogen binding during hybridization with its target produce electrical signals measured by KEITHLEY 2450 (Source Meter). The genosensor validated with different types of targets such as complimentary, non-complementary and single mismatch oligonucleotides. The serial dilution of target concentration has been experimented triplicate (n=3) range from 1fM to 10μM. The slope of calibration curve resulted 2.389E-0 AM-1 with regression coefficient (R2) = 0.97535.
  • Publication
    Hydrothermal growth zinc oxide nanorods for pH sensor application
    ( 2023-10)
    Foo Kai Loong
    ;
    Tan Soo Jin
    ;
    Heah Cheng Yong
    ;
    Subash Chandra Bose Gopinath
    ;
    Liew Yun Ming
    ;
    Uda Hashim
    ;
    Voon Chun Hong
    The aim of this work is to apply synthesized zinc oxide (ZnO) Nanorods using hydrothermal (HTL) growth technique for pH sensor application. The highly crystallite of ZnO Nanorods was obtained by anneal the growth ZnO Nanorods in furnace at 200°C for 2 hours. Besides that, XRD analysis shows the produced ZnO Nanorods belonged to the (002) plane. Furthermore, Scanning Electron Microscope (SEM) images confirm that the ZnO Nanorods with hexagonal-faceted structural were successfully produced by HTL growth technique. In addition, Ultraviolet–visible (UV-Vis) spectrophotometer analysis shows that the synthesized ZnO belongs to the wide band gap semiconductor material. The growing ZnO Nanorods were then subjected to electrical measurement with various pH levels. The outcome demonstrates that the current rises as the solution changes from acidic to alkaline. Overall, our study shows a relationship between the electrical as well as the structural characteristics of ZnO Nanorods at various pH levels.
  • Publication
    Preparation and characterization of tensile properties of PMMA-SiC nanowhiskers nanocomposite films: effect of filler loading and silane treatment
    ( 2023-10)
    Lim Bee Ying
    ;
    Voon Chun Hong
    ;
    L. Y. Lee
    ;
    Teh Pei Leng
    ;
    P. Y. Foong
    The preparation of nanocomposites through melt mixing was challenging as the nanofillers tend to form agglomeration. The silicon carbide nanowhiskers (SiCNWs) filled poly (methyl methacrylate) (PMMA) thin film in this study was prepared by means of solution casting. Acetone with low toxicity was used as solvent to dissolve the PMMA pellets. A coupling agent, silane was used to enhance the properties of composite films. Besides, the untreated and treated SiCNWs were filled into PMMA matrix, respectively with the filler loading varied from 0.2 to 0.8 wt%. The universal testing machine was used to investigate the tensile properties of composites. It was found out that the tensile strength of the PMMA was reduced in the presence of SiCNWs. However, the tensile strength had increased with the rise of filler loading. At 0.8 wt% of SiCNWs, the composites’ tensile strength was comparable to virgin PMMA. Meanwhile, the SiCNWs had reduced the elongation at break but increased the elastic modulus of PMMA/SiCNWs nanocomposite films. In addition, silane surface treatment on SiCNWs had improved the tensile strength and ductility but lowered the elastic modulus of the nanocomposites. The improvement was due to the enhancement of interfacial adhesion between SiCNWs and PMMA.
  • Publication
    Biotechnological processes in microbial Amylase production
    ( 2017)
    Subash C. B. Gopinath
    ;
    Periasamy Anbu
    ;
    Mohd Khairuddin Md Arshad
    ;
    Thangavel Lakshmipriya
    ;
    Voon Chun Hong
    ;
    Uda Hashim
    ;
    Suresh V. Chinni
    Amylase is an important and indispensable enzyme that plays a pivotal role in the field of biotechnology. It is produced mainly from microbial sources and is used in many industries. Industrial sectors with top-down and bottom-up approaches are currently focusing on improving microbial amylase production levels by implementing bioengineering technologies. The further support of energy consumption studies, such as those on thermodynamics, pinch technology, and environment-friendly technologies, has hastened the large-scale production of the enzyme. Herein, the importance of microbial (bacteria and fungi) amylase is discussed along with its production methods from the laboratory to industrial scales.
  • Publication
    Development of anodised aluminium oxide nanostructure from Al-Mn alloy
    ( 2013)
    Voon Chun Hong
    This study was divided into two parts. The first part of the study was focused on the synthesis of well ordered porous AAO by using oxide dissolution treatment. The porous AAO was formed by anodising of 99.99 % aluminium in 0.3 M oxalic acid at 15 oC for 15 minutes. Anodised substrates were subjected to oxide dissolution treatment by immersing in stirred mixture of chromic acid and phosphoric acid. The effect of oxide dissolution treatment on the morphology and regularity of porous AAO was studied by using scanning electron microscope. The results showed that exposure of porous AAO to oxide dissolution treatment up to three minutes revealed the well ordered pores arrangement that formed during the steady state growth stage. Regularity of the porous AAO was improved. In the second part of the study, porous AAO was formed from aluminium manganese (Al-Mn) alloy substrates and the effect of manganese content, anodising voltage, concentration of oxalic acid, and temperature of oxalic acid on the anodising behaviour, morphology, dimensional properties and growth kinetics were studied. Results showed that the addition of Mn from 0.5 wt % to 2.0 wt % into Al substrates reduced the current density, regularity and growth kinetics of porous AAO. The pore size and interpore distance were also found to decrease with the addition of Mn. Anodising efficiency of anodising process decreased as the Mn content increased up to 1.0 wt %, but increased when the Mn content was further increased to 2.0 wt %. Analysis of XRD patterns showed that amorphous alumina was formed in substrates of all compositions and MnO2 was found to present in Al-1.5 wt % Mn and Al -2.0 wt % Mn substrates. For the study of effect of anodising voltage, anodising of Al-0.5 wt % Mn under the influence of increasing anodising voltage of 30-70V has led to higher current density, larger pore size and interpore distance and higher growth rates. The regularity of pore arrangement of porous AAO was improved when the anodising voltage was increased from 30 V to 50V, but deteriorated when further increased to 70V. Dielectric breakdown occurred when anodising was conducted at 70V. Amount of amorphous alumina was found to increase when the anodising voltage was increased from 30 V to 70 V. Anodising of Al-0.5 wt % Mn at 50 V in oxalic acid of increasing concentration from 0.1 M to 0.7 M increased the current density and growth kinetics. Well ordered porous AAOs were obtained when oxalic acid of all concentration was used, except 0.1 M. Increase of concentration of oxalic acid decreased the pore size while no significant difference in interpore distance was observed. Anodising efficiency decreased as a function of concentration of oxalic acid. The relative intensity of broad peaks in XRD patterns showed that amount of amorphous alumina increased as a function of concentration of oxalic acid. For the study of effect of temperature of oxalic acid, anodising of Al-0.5 wt % Mn was conducted at 50V in 0.5 M oxalic acid of temperature ranging from 5oC to 25oC. Current density and oxide thickness increased while regularity of pores arrangement and anodising efficiency decreased with the increasing temperature of oxalic acid. Temperature of oxalic acid did not have obvious effect on both pore size and interpore distance. Relative intensities of broad peaks increased indicating the amount of amorphous alumina increased with the increasing temperature of oxalic acid.
  • Publication
    Dielectric and mechanical properties of PLA-carbon composites
    ( 2024-04)
    Mathanesh Thangarajan
    ;
    Yeoh Cheow Keat
    ;
    Teh Pei Leng
    ;
    Wee Chun Wong
    ;
    Chong Hui Yew
    ;
    Kang Zheng Khor
    ;
    Nor Azura Abdul Rahim
    ;
    Voon Chun Hong
    This study focuses on the development and characterization of Carbon-based Polylactide (PLA) composites for 3D printer filaments. The aim is to enhance the electrical and mechanical properties of PLA by incorporating recovered carbon black (RCB) in different mesh sizes (500, 1000, 1500, and 2000 mesh). Electrical impedance spectroscopy and dielectric constant measurements were performed to investigate the electrical properties of the composites. Results showed that the addition of RCB increased the dielectric constant, with values ranging from 2.5 to 7.1, indicating improved electrical performance. Scanning electron microscopy (SEM) analysis revealed the dispersion of carbon particles within the composites, enhancing their electrical conductivity. The effect of RCB particle size on electrical properties was also explored, with smaller particle sizes (2000 mesh) resulting in the highest conductivity of 6.2 S/m. Tensile testing demonstrated that the addition of RCB increases the tensile strength of PLA, with values ranging from 28.6 MPa to 47.2 MPa, and the elastic modulus, ranging from 832 MPa to 1.56 GPa, depending on the mesh size. The optimal combination of RCB content and mesh size resulted in a composite with a tensile strength of 43.8 MPa. Overall, this research provides insights into the development of Carbon-based PLA composites with improved electrical and mechanical properties.