2018 Volume 65 Issue 9 Pages 548-553
New production method of nano-crystals was proposed. Over the past few decades, with improvements in nanotechnology, production of nano-materials had been paid interest markedly. There are some production methods of nano-materials, such as inert gas evaporation method, hydrothermal synthesis method, mechanical grinding method and etc. In recently, solution plasma method was developed, in that method nano-crystals were produced by microwave induced plasma in liquid. The authors have found new nano-crystal production method. In the new method, nano-crystals were produced by application of relatively low voltage DC current in aqueous electrolyte solution. The various combinations of electrodes (Au, Cu, W, Si, etc.) and aqueous electrolyte solution (Na2SiO3, Na2CO3, Na2SO4, etc.) were tested to produce nano-crystals. After few tens minutes of current application, precipitated materials were gathered and identified by X-ray diffraction analysis and TEM observation. From XRD analysis and TEM observation, it was found that the collected materials were nano-crystals of around few tens nm of the same material as the electrode. From measurement of mass change of electrode before and after DC current application, it turned out that nano-crystals were generated from the electrode to which the positive voltage was applied.