Now showing 1 - 2 of 2
  • Publication
    rGO-SWCNT hybrid for counter electrode in dye sensitized solar cell
    (Universiti Malaysia Perlis (UniMAP), 2018-12)
    M. R. Muda
    ;
    Siti S. Mat Isa
    ;
    Towards platinum free counter electrode in dye sensitized solar cells, some carbon-based materials like carbon nanotubes and graphene are fully utilized due to their extraordinary properties such as high aspect ratio and conductivity. In this paper, single-walled carbon nanotubes (SWCNT), reduced graphene oxide (rGO) and hybrid structure of rGO-SWCNT spray coated counter electrodes were compared with graphite as the reference material. The morphology of these materials was analyzed with FESEM and FTIR. The DSSC performance was then measured using solar simulator. The current-voltage (I-V) characteristics show that the rGO-SWCNT counter electrode result the excellent performance with efficiency of ~1.86 %, 95.2 % better than graphite. This higher performance was attributed by the complete oxygen-functional group removal during reduction process which offers large active surface area for electro-photocatalytic activity, higher conductivity, better structure and properties compared to the individual forms.
      1  17
  • Publication
    Evaluation of GO and rGO on breast cancer cell line (MCF7) and normal breast cell line (MCF10a) for cell viability and electrical response
    (Universiti Malaysia Perlis (UniMAP), 2018-12)
    Siti S. Mat Isa
    ;
    N. S. Mazlan
    ;
    ;
    L. F. A. Talip
    ;
    Rafeezul Mohamed
    ;
    Graphene based materials become a phenomenal in various applications including biomedical devices due to their excellent properties. Their effects towards certain diseases were broadly studies and presented. However, the work has been performed was only limited to the graphene oxide (GO) and its biocompatibility only. In this work, the interaction of GO and reduced graphene oxide (rGO) on breast cancer cell (MCF7) and normal breast cell (MCF10a) was investigated specifically on the cell viability, cell mortality and current-voltage (IV) relationship. Graphene oxide and rGO at the concentration of 100μg/mL were prepared by chemical methods. The morphology and quality of both materials were characterized using AFM and Raman Spectroscopy. The cells were treated for 24 hours and the effects of these materials on the viability and mortality of the cell were observed. The interaction between graphene-based materials and both cells significantly impact the current-voltage (IV) characteristics. The results show that GO and rGO did not affect the cell viability but only small percentage different was obtained on cell mortality. It also observed that the resistance of cell treated with rGO decreased with time for MCF7 and vice versa for MCF10a. While for GO, the resistance of cell increased with time for MCF7 and vice versa for MCF10a. These clear patterns of these interactions lead to a good input for biosensor fabrication which was aimed to be used as the early diagnosis cancer stem cell point of care (POC) device.
      4  15