Nur Hamidah Abdul Halim
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Preferred name
Nur Hamidah Abdul Halim
Official Name
Nur Hamidah, Abdul Halim
Alternative Name
Halim, Nur Hamidah Abdul
Halim, N. H.A.
Hamidah A Halim, N.
Halim, N. H.
Halim, N. Hamidah A.
Abdul Halim, Nur Hamidah
Main Affiliation
Scopus Author ID
55493444600

Research Output
Now showing 1 - 2 of 2
  • Publication
    Electrical simulation on silicon nanowire field-effect transistor biosensor at different substrate-gate voltage bias conditions for charge detection
    ( 2022-12)
    X.Y. Teoh
    ;
    Mohamad Faris Mohamad Fathil
    ;
    Y.M.Tan
    ;
    Norhayati Sabani
    ;
    Mohammad Nuzaihan Md Nor
    ;
    Mohd Khairuddin Md Arshad
    ;
    Ruslinda A. Rahim
    ;
    Nur Hamidah Abdul Halim
    ;
    Ramzan Mat Ayub
    ;
    Uda Hashim
    ;
    M.M. Ibrahim
    In this work, the impact of different substrate-gate voltage bias conditions (below and above the device threshold voltage) on current-voltage characteristics and sensitivity of a silicon nanowire field-effect transistor (SiNW-FET) biosensor was investigated. A 3-dimensional device structure with n-type SiNW channel and a substrate gate electrode was designed and electrically simulated In the Silvaco ATLAS. Next, the SiNW channel was covered with a range of interface charge density to mimic the charged target biomolecule captured by the device. The outcome was translated into a drain current versus interface charge semi-log graph and the device sensitivity was calculated using the linear regression curve’s slope of the plotted data. The device’s electrical characteristic shown higher generation of output drain current values with the increase of negative substrate-gate voltage bias due to the hole carriers’ accumulation that forms a conduction channel in the SiNW. Application of higher negative interface charge density increased the change in drain current, with the device biased with higher substrate-gate voltage shows more significant change in drain current. The device sensitivity increased when biased with higher substrate-gate voltage with highest sensitivity is 75.12 nA/dec at substrate-gate voltage bias of –1.00 V.
      2  17
  • Publication
    Optimization of gold nanoparticles electrodeposition duration on screen printed electrode to enhance electrochemiluminescence of nitrogen-doped carbon dots
    ( 2023-12)
    Nurul Izzati Akmal Mohd Azman
    ;
    Nur Syakimah Ismail
    ;
    Nur Hamidah Abdul Halim
    ;
    Nurjuliana Juhari
    ;
    Norhayati Sabani
    ;
    Toibah Abd Rahim
    ;
    Siti Aisyah Shamsudin
    ;
    Eiichi Tamiya
    In this work, the electrodeposition method was utilized to form gold nanoparticles on a carbon screen-printed electrode (SPE) using chronoamperometry at -0.4 V with various durations from 50 to 200 seconds. Scanning Electron Microscopy (SEM) images have proven that the electrodeposition method is capable of uniformly forming AuNPs on SPE (AuNPs- SPE). Apart from that, electrodeposition durations have increased the size of AuNPs by up to 66% based on average size measurements using ImageJ software. It can be observed that long electrodeposition durations permit the agglomeration of AuNPs on the electrode surface. The effect of electrodeposition duration on electrocatalytic performance in potassium ferricyanide and electrochemiluminescence (ECL) intensity of nitrogen-doped carbon dots (NCDs) was evaluated. Cyclic voltammetry (CV) of ferricyanide demonstrates that as the electrodeposition duration increases, AuNPs-SPE shows better electrochemical performance than bare SPE. ECL of NCDs displays that 100 s electrodeposition durations give the highest ECL intensity of 184% compared to bare SPE and have been chosen as the optimum parameter. The ECL mechanisms of bare SPE and AuNPs-SPE reveal that AuNPs- SPE has greater electrochemical and ECL performance than bare SPE, as evidenced by the CV of AuNPs-SPE having a faster reduction current, which rises to 87.2% ECL intensity and 510 mV faster ECL occurrence. These phenomena confirmed that the electrodeposition of AuNPs has improved the conductivity of SPE.
      6  3