Fabrication of Low‐cost Screen‐printed Electrode in Paper Using Conductive Inks of Graphite and Silver/Silver Chloride

Abstract

The fabrication of the Screen‐Printed Electrode (SPE) was performed using the graphite ink to print the working (WE) and counter electrodes (CE), and silver/silver chloride path as reference electrode (RE). All the electrodes are printed in a paper substrate using screen‐printing technique. The resulting SPE is characterized using scanning electron microscopy, showing all the ink layer, and subsequently optimized. The paper sample presented the cellulose fibers entanglement, extremely rough, with highly porous network. Then the graphite ink was deposited and the surface became flat, thinner and very smooth. When the silver ink was painted on top of the graphite ink, the spherical silver particles, ranged from 2–3.5 μm in size, were observed. And finally, the silver ink was covered with a AgCl layer and the particle size becomes larger with an irregular sphere‐like phase. The images showed that the layers appear to be homogeneously distributed with good coverage. Then fabrication process was optimized concerning type of paper, the sanding process, the hydrophobic barrier, the electrode design and size. In summary, the optimized values included using the previously sanded matte paper with a mineral spirit layer. The design and size of the electrode were also tested to achieve the best electrochemical performance (design 3 with 3.5 cm). The final SPE was a miniaturized and flexible paper‐based electrochemical electrode. In order to evaluate the electrical properties, the ohmic resistance of each ink was tested using a multimeter and the obtained values were 2.18 kΩ for the graphite ink, 2.27 Ω for the silver ink and 38.33 kΩ for the silver/silver chloride ink. That can indicate the good conductivity of each ink used in the fabrication of the electrode and the correct deposition of Ag/AgCl. Finally, the electrode was used to measure the electrochemical response of K4[Fe(CN)6] in different concentrations. Then a calibration curve was obtained from the voltammograms and a linearity was observed between the current and concentration in the range of 0.50–2.00 mM. That indicates that the SPE has potential to be used as a voltammetric electrode.

Optimizing Capacitive Pressure Sensor Geometry: A Design of Experiments Approach with a Computer-Generated Model

“…PDMS has been widely utilized as a flexible dielectric material [ 20 ] and diaphragm in capacitive pressure sensors, owing to its favorable characteristics, including low Young’s modulus, flexibility, biocompatibility, and excellent dielectric properties [ 21 , 22 ]. Silver is used as the electrode material in most capacitive applications [ 23 , 24 , 25 , 26 ]. Moreover, owing to its high dielectric value and mechanical flexibility, PVDF is employed as a dielectric material [ 27 ].…”

Disposable Voltammetric Immunosensor for Determination and Quantification of Biomarker CA 15-3 in Biological Specimens

“…Graphite and silver inks were prepared according to the procedure outlined in our previous studies [21,22]. The fabrication and characterization of the SPE are described in detail in our previous work [23]. Briefly, a stencil was cut from clear sticker paper using a cutter plotter.…”

Electrochemical Determination of Catechol Using a Disposable Printed Electrode with Conductive Ink Based on Graphite and Carbon Black

“…The printing technique to be used must be suitable for the type of ink chosen. Various techniques are employed in the manufacture of printed electrodes, and the most common is screen-printing [15][16][17][18][19][20][21][22][23][24].…”