화학적 환원법으로 제작한 은나노유체의 흡광계수

Abstract

Abstract In this study, we prepare the Ag nanofluids synthesized by the chemical reduction method and measure the extinction coef-ficient of those nanofluids at a wavelength of 632.8 nm. The Ag nanofluids are synthesized by the chemical reductionmethod using silver nitrate (AgNO 3 ) and sodium borohydride (NaBH 4 ) in water and ethylene glycol (EG). For stable disper-sion of Ag particles in the base liquids, polyvinyl pyrrolidone (PVP) is added as a surfactant. The extinction coefficient ofmanufactured Ag nanofluids is measured by an in-house developed measurement system at the wavelength of 632.8 nm. Theresults show that the extinction coefficient of water-based and EG-based Ag nanofluids is linearly increased with respect tothe particle loadings. Moreover, it is shown that the extinction coefficient of EG-based Ag nanofludis is higher than that ofwater-based Ag nanofluids. Finally we compare the experimental results with both the Maxwell-Garnett model and Rayleighscattering approximation model, and they demonstrate that the Rayleigh scattering approximation model is reasonably predictthe extinction coefficient of Ag nanofluids using hydraulic diameter of silver nanoparticle.