PEAK CURRENT PARAMETERS OF MOLYBDENUM NANOCOLLOIDS PREPARED BY ELECTRICAL SPARK DISCHARGE METHOD
Abstract - This study used the Electrical Spark Discharge Method to prepare molybdenum nanocolloids (MNC). The equipment and materials used for its preparation include an electrical discharge machining machine, 99.9% pure molybdenum wires, and deionized water. In this study, colloids were prepared with seven peak current parameters when the process time parameter Ton - Toff was 10-10 μs; the preparation time was 3 minutes. The analysis of UV-Vis and Zetasizer showed that the prepared MNChad the best colloidal properties when the peak current parameter was IP7, with a wavelength of 216 nm, an absorbance of 2.555, an average particle size of 188.6 nm, and a ζ potential of -32.9 mV. Transmission electron microscopy images showed that the shape of the colloidal particles was close to spherical, and the minimum particle size was about 13.27 nm. The properties of this colloid proved that the electrical spark discharge method could prepare MNCs with good suspension. Oscilloscope analysis showed that the discharge success rate of preparing the colloid was 60 %. When the spark discharge was successful, the interelectrode gap voltage and current were about 125 V and 10A, respectively. Suspending agent was not added in the preparation of the colloid. Hence, when applying this colloid in fields of environmental pollution prevention and biomedicine, it is not needed to consider the possible adverse effects of the colloid containing elements other than molybdenum.
Keywords - Electrical Spark Discharge Method, Molybdenum Nanocolloids, Absorbance, Interelectrode Gap