In-Liquid Plasma Process for Size- and Shape-Controlled Synthesis of Silver Nanoparticles by Controlling Gas Bubbles in Water

Abstract

Most methods controlling size and shape of metal nanoparticles are chemical methods, and little work has been done using only plasma methods. Size- and shape-controlled synthesis of silver nanoparticles (Ag NPs) is proposed based on adjusting the gas bubble formation produced between two silver electrodes. The application of a voltage waveform with three different pulse widths during a plasma process in water can generate different gas bubble formations. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) images of Ag NPs synthesized using three different bubble formations reveal that spherical Ag NPs are synthesized when very tiny bubbles are generated between two electrodes or when only the grounded electrode is enveloped with large gas bubbles, but Ag nanoplates are synthesized when both electrodes are completely enveloped with large gas bubbles.

Engineering the surface morphology of inkjet printed Ag by controlling solvent evaporation during plasma conversion of AgNO3 inks

“…55,56,61 The concentration and size of Ag nuclei continually rises in this region during the plasma conversion process, eventually reaching a level sufficient to trigger nucleation and growth of 3D structures in the near surface region where the plasma electrons have their strongest influence. The as-formed Ag nanoparticles can diffuse through from the film surface through the bulk of the liquid within a couple of minutes, 62 so they are unlikely to accumulate. The Ag nanoparticles may aggregate due to their high surface energy, but forming large “raft” structures is unlikely in the presence of solvents because the low temperature plasma is not hot enough to rapidly remove the solvent molecules surrounding the Ag nanoparticles.…”

In-Situ Iodine Doping Characteristics of Conductive Polyaniline Film Polymerized by Low-Voltage-Driven Atmospheric Pressure Plasma

“…The diagnostic use of optical emission spectroscopy (OES) for light-emitting regions allows a better understanding of highly complex phenomena such as high-pressure plasma, dusty plasma, and solution plasma [ 48 , 49 , 50 ]. A fiber optic spectrometer (USB-2000+, Ocean Optics Inc., Dunedin, FL, USA) was employed to identify a variety of reactive species generated by the glow plasma during the AP plasma polymerization process.…”

Surfactant-free colloidal syntheses of precious metal nanoparticles for improved catalysts

“…In some cases, indeed, the electrode itself is the source of the NPs rather than a precursor being reduced. Shape control was even reported by tuning the gas bubbles formed in liquid elelctrolyte 145 or precursor concentration. 139 The approach has been shown to be suitable to obtain surfactant-free NPs as diverse as Ni 146 , Au, 138,141 Pt, 113,142 Pd, 113 Rh 113 or even TiO2 nanorods.…”