The Effect of Plasma Parameters on the Structural Properties of SiO2/Au Core Shell Nanostructure

Abstract

Plasma diagnostics play a pivotal role in understanding plasma behavior and properties in various environments, which enables us to control the plasma parameters required for a suitable application, such as nanoparticle production. In this work, the underwater plasma was generated by exploding gold wires in a SiO₂ suspension. The process is controlled by an Arduino-based system that precisely regulates the circuit, ensuring accurate replication of each pulse. The optical emission spectroscopy (OES) is used to diagnose the plasma simultaneously.
Boltzmann plot was used to calculate the electron temperature, which ranged from 8.374 eV to 10.321 eV and the electron density is determined through Stark broadening, which increased from 0.166 ×1018 (cm-3) to 0.449×1018 (cm-3), indicating a direct proportionality between the applied current and the plasma parameters.
The X-ray diffraction (XRD) analysis showed that the nanostructures contained an FCC Au structure with crystallite sizes ranging from 12 to 34 nm.