Chih-Hung Lo

Process development and photocatalytic property of nanofluid prepared by combined ASNSS

Abstract This study proposes a new method: the combined arc-submerged nanoparticle synthesis system (ASNSS) for preparing TiO2 nanofluid. In addition to the influence of the various process variables such as breakdown voltage, peak current and dielectric liquid temperature on nanoparticles, this study will also discuss the photocatalytic activity of the prepared TiO2 nanoparticle suspension. To examine the photocatalytic activity of the TiO2, the photodecomposition of salicylic acid was carried out. Experimental results show that the proposed method can successfully prepare anatase TiO2 and this nanofluid can be stabilised for longer than six months. The rate constant of photocatalytic reaction of TiO2 nanoparticles for salicylic acid is 0·0035. Experimental results indicate that the TiO2 nanoparticle fluid possesses excellent photocatalytic activity in photodegradation of salicylic acid.

Fabrication and characterization of CuO nanorods by a submerged arc nanoparticle synthesis system

The purpose of this study is to investigate an innovative nanorod preparation method, the submerged arc nanoparticle synthesis system. The key parameters such as discharge current, breakdown voltage, pulse duration, and temperature of the dielectric liquid are carefully analyzed in order to obtain more uniform nanorods. The prepared nanorods were systematically characterized by x-ray diffraction, transmission electron microscopy, selected-area electron diffraction, x-ray photoelectron spectroscopy, and the ultraviolet-visible absorption spectrum. The results showed that the CuO nanorods had a diameter of 30–50nm and a longitudinal length of up to 1–2μm. A possible preparation mechanism was also discussed for the growth of the CuO nanorods.

High Thermal Conductivity Nanofluid Fabrication by Continuously Controlled Submerged Arc Nano Synthesis System (CC-SANSS)

The purpose of this study is to innovative high thermal conductivity Cu-based nanofluid preparing method, the continuous control submerged arc nano synthesis system (CC-SANSS). The key parameters such as current, voltage, pulse-duration, electric resistance and temperature of the de-ionized liquid are investigated carefully in order to obtain more uniform nanoparticles suspension in nanofluids. The morphology of nanoparticles prepared in de-ionized liquid exhibits the needle-like shape, with an average width of 20nm and length of 80nm. In addition, transient hot-wire method is used to measure the thermal conductivity properties of nanofluids. It is found that improvement of thermal conductivity are 35.99%, 18.26%, 8.5%, 1.95%, respectively when ingredient of nanofluids are 2.0%, 1.0%, 0.5%, 0.1% Volume at 30°Cwater-based nanofluids containing copper oxide nanoparticle. Experimental result shows that better thermal properties are obtained when low concentration nanofluids produced by CC-SANSS are compared to the ones produced by other processes.