Synthesis of copper/copper oxide nanoparticles by solution plasma

Journal of Applied Physics

Nakasugi

Akiyama

2014

Self Cite

Excitation temperature of a solution plasma was investigated by spectroscopic measurements to control the nanoparticle synthesis. In the experiments, the effects of edge shielding, applied voltage, and electrode material on the plasma were investigated. When the edge of the Ni electrode wire was shielded by a quartz glass tube, the plasma was uniformly generated together with metallic Ni nanoparticles. The emission spectrum of this electrode contained OH, H-alpha, H-beta, Na, O, and Ni lines. Without an edge-shielded electrode, the continuous infrared radiation emitted at the edge created a high temperature on the electrode surface, producing oxidized coarse particles as a result. The excitation temperature was estimated from the Boltzmann plot. When the voltages were varied at the edge-shielded electrode with low average surface temperature by using different electrolyte concentrations, the excitation temperature of current-concentration spots increased with an increase in the voltage. The size of the Ni nanoparticles decreased at high excitation temperatures. Although the formation of nanoparticles via melting and solidification of the electrode surface has been considered in the past, vaporization of the electrode surface could occur at a high excitation temperature to produce small particles. Moreover, we studied the effects of electrodes of Ti, Fe, Ni, Cu, Zn, Zr, Nb, Mo, Pd, Ag, W, Pt, Au, and various alloys of stainless steel and Cu-Ni alloys. With the exception of Ti, the excitation temperatures ranged from 3500 to 5500 K and the particle size depended on both the excitation temperature and electrode-material properties

Section: Methodsmentioning

confidence: 99%

“…In a previous study, we synthesized copper nanoparticles by using a sodium citrate solution. 23 The high voltage with a partial plasma was effective for size control of various materials, as described in Secs. III A and III B.…”

Section: Effects Of the Electrode Materialsmentioning

confidence: 99%

Excitation temperature of a solution plasma during nanoparticle synthesis

Journal of Applied Physics

Nakasugi

Akiyama

2014

Self Cite

“…As reported previously, 13 the experimental setup consisted of two electrodes in a glass cell with a capacity of 300 ml. The cathode consisted of a Ni wire with a diameter of 1.0 mm and purity of more than 99.9 mass% (Kojundo chemical, Saitama, Japan) placed at the center of the glass cell.…”

Section: Experiments a Experimental Setupmentioning

confidence: 99%

“…12) and CuO. 13 In addition, the size and composition of these nanoparticles can be controlled by changing the experimental conditions. 14,15 This method for producing nanoparticles has many advantages: (1) it requires a simple experimental setup without the need for a vacuum chamber; (2) there is no need to supply any gas; (3) a conductive electrode is used as the raw material, and harmful reductants or expensive agents are not required; and (4) it can be applied to any electrically conductive metal/alloy.…”

Section: Introductionmentioning

confidence: 99%

Surface morphology of a glow discharge electrode in a solution

Journal of Applied Physics

Hosokai

Tsubota

et al. 2012

Self Cite

Phase-field modeling of three-phase electrode microstructures in solid oxide fuel cells Appl. Phys. Lett. 101, 033909 (2012) Dynamic modelling and simulation of a polymer electrolyte membrane fuel cell used in vehicle considering heat transfer effects J. Renewable Sustainable Energy 4, 043107 (2012) Colloidal electroconvection in a thin horizontal cell. III. Interfacial and transient patterns on electrodes J. Chem. Phys. 137, 014504 (2012) Use of magnetite as anode for electrolysis of water J. Appl. Phys. 111, 124911 (2012) Additional information on J. Appl. Phys. This paper describes the surface morphology of a glow discharge electrode in a solution. In the experiments detailed in the paper, the effects of electrolysis time, solution temperature, voltage, electrolyte concentration, and surface area on the size of nanoparticles formed and their amount of nanoparticles produced were examined to study the surface morphologies of the electrodes. The results demonstrated that the amount of nanoparticles produced increased proportionally with the electrolysis time and current. When the voltages were below 140 V, surfaces with nanoparticles attached, called "Particles" type surfaces, were formed on the electrode. These surfaces changed and displayed ripples, turning into "Ripple" type surfaces, and the nanoparticle sizes increased with an increase in the amount of nanoparticles produced. In contrast, at voltages over 160 V, the surfaces of the electrodes were either "Random" or "Hole" type and the particle sizes were constant at different amount of nanoparticles produced. V C 2012 American Institute of Physics.

“…Some of these methods successfully produced small (<10 nm) uniform nanoparticles. In particular, solution plasma has been applied to the synthesis of microparticles/nanoparticles in solution [27][28][29]. A nickel electrode, placed at the center of a beaker, acts as the cathode in this method.…”

Section: Introductionmentioning

confidence: 99%

Nickel Nanoparticles Formation from Solution Plasma Using Edge-Shielded Electrode

Plasma Chem Plasma Process

Hosokai

Tsubota

et al. 2011

Abstract. Because of the easy massproduction, synthesis of metallic nanoparticles from a solution plasma is an attractive method. However, a solution plasma produces a highly inhomogeneous electric field via transition to full-plasma, and the products are partially oxidized and agglomerated, with a wide size-distribution. Here, we show a simple method of suppressing oxidation of products. An electrode tip was shield by a glass tube and a voltage of up to 180 V was applied with the electrolyte of 0.1 M NaOH solution. Significantly, the edge-shield was quite effective for maintaining partially glow discharge. The results were (1) surface temperature of the electrode less than 100 °C, (2) main phase of metallic nickel evaluated by XRD, and (3) nanoparticles of an average size of 220 nm. These results showed the potential for an application to the production of nanoparticles.