Solution Plasma Process Synthesis and Characterization of Copper Nanoparticles for Enhanced Photocatalytic...

Developing low-cost, highly active plasmonic metal nanoparticles has become a prominent topic in the field of new energy research. The solution plasma process (SPP) for synthesizing copper nanoparticles is expected to produce metallic copper nanoparticles (CuNPs) with a reduced tendency to oxidize. During this process, the electrolyte solution determines the chemical state and morphology of the synthesized nanoparticles. In this study, we report that a higher electrolyte concentration (70 mM) yields metallic CuNPs, whereas a lower concentration (30 mM) produces smaller nanoparticles in an oxidized state (+1). The nanoparticles prepared at different concentrations exhibited distinct absorption characteristics in their UV-visible spectra, providing a means for analyzing the catalytic activity of both types of copper nanoparticles when supported onto a base catalyst, thereby affording a foundational understanding of photocatalytic activity when CuNPs are supported on a gallium oxide photocatalyst.