Fabrication and Characterisation of the Electrical and Physical Properties of the Mask Printed Graphite Paste Electrodes on Paper Substrates

Heavy metal contamination in waste water is a problem of paramount concern. Instant measurement of the degree of contamination is the long term aim of this work. This project proposed the fabrication of mask printed graphite paste electrodes based on natural graphite and micronized graphite powder which has potential for sensing heavy metal in water. The graphite paste were prepared by mixing paraffin oil and graphite powder at certain ratios and they were coated via a mask on a paper substrate using squeegee method. A two-probe station was used to characterize the I-V curve of the mask printed electrodes, in which the result was used for determining the resistivity of the graphite paste electrodes. A field emission scanning electron microscope (FE-SEM) and energy dispersive X-ray spectroscopy (EDS) was used to investigate the surface structure of the graphite paste electrode and determining the purity of the carbon in the electrode. The result shows that natural and micronized graphite paste electrode has a mean resistivity of 1.69 x 10^-3 Ωm and 1.25 x 10^-3 Ωm, respectively. The slight difference found in the conductivity of both electrodes is associated with the particle gap size, density and dimension of graphite electrodes which are associated with the percolation theory.