Foo Kai Loong
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Preferred name
Foo Kai Loong
Official Name
Foo, Kai Loong
Alternative Name
Loong, Foo Kai
Kai Loong, Foo
Foo, K. L.
Foo, Kai Loong
Foo, Kai Long
Main Affiliation
Scopus Author ID
37012449500
Researcher ID
D-2035-2015

Research Output
Now showing 1 - 6 of 6
  • Publication
    Low temperature annealed zinc oxide nanostructured thin film-based transducers: Characterization for sensing applications
    ( 2015)
    R. Haarindraprasad
    ;
    Uda Hashim
    ;
    Subash Chandra Bose Gopinath
    ;
    Muhammad Kashif
    ;
    P. Veeradasan
    ;
    S. R. Balakrishnan
    ;
    Foo Kai Loong
    ;
    Prabakaran A/L Poopalan
    The performance of sensing surfaces highly relies on nanostructures to enhance their sensitivity and specificity. Herein, nanostructured zinc oxide (ZnO) thin films of various thicknesses were coated on glass and p-type silicon substrates using a sol-gel spin-coating technique. The deposited films were characterized for morphological, structural, and optoelectronic properties by high-resolution measurements. X-ray diffraction analyses revealed that the deposited films have a c-axis orientation and display peaks that refer to ZnO, which exhibits a hexagonal structure with a preferable plane orientation (002). The thicknesses of ZnO thin films prepared using 1, 3, 5, and 7 cycles were measured to be 40, 60, 100, and 200 nm, respectively. The increment in grain size of the thin film from 21 to 52 nm was noticed, when its thickness was increased from 40 to 200 nm, whereas the band gap value decreased from 3.282 to 3.268 eV. Band gap value of ZnO thin film with thickness of 200 nm at pH ranging from 2 to 10 reduces from 3.263eV to 3.200 eV. Furthermore, to evaluate the transducing capacity of the ZnO nanostructure, the refractive index, optoelectric constant, and bulk modulus were analyzed and correlated. The highest thickness (200 nm) of ZnO film, embedded with an interdigitated electrode that behaves as a pH-sensing electrode, could sense pH variations in the range of 2-10. It showed a highly sensitive response of 444 μAmM-1cm-2 with a linear regression of R2 =0.9304. The measured sensitivity of the developed device for pH per unit is 3.72μA/pH.
  • 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
    Morphological, structural, and electrical characterization of sol-gel-synthesized ZnO nanorods
    ( 2013-02-03)
    M. Kashif
    ;
    Uda Hashim
    ;
    M. E. Ali
    ;
    Foo Kai Loong
    ;
    Syed M. Usman Ali
    ZnO nanorods were grown on thermally oxidized p-type silicon substrate using sol-gel method. The SEM image revealed high-density, well-aligned, and perpendicular ZnO nanorods on the oxidized silicon substrate. The XRD profile confirmed thec-axis orientation of the nanorods. PL measurements showed the synthesized ZnO nanorods have strong ultraviolet (UV) emission. The electrical characterization was performed using interdigitated silver electrodes to investigate the stability in the current flow of the fabricated device under different ultraviolet (UV) exposure times. It was notified that a stable current flow was observed after 60 min of UV exposure. The determination of stable current flow after UV exposure is necessary for UV-based gas sensing and optoelectronic devices.
  • 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.