[20p-P12-1~31] 12.7 Biomedical Engineering and Biochips

[20p-P12-12] Optical properties of gold nano-particles attached on zinc oxide particles

Mari Iizuka¹, 〇Masatoshi Fujii¹, Hideki Hashimoto², Yasuhisa Fujita³ (1.Shimane Univ., 2.Shimane Univ.1, 3.Shimane Univ.2)

Keywords:zinc oxide,nano-particle,Optical property

Zinc oxide, ZnO, is a wide band gap 3.4 eV semiconductor, having high exiton binding energy of 60 meV; it is used as ultraviolet light emitters. On the other hand, ZnO particles are widely used as safety white pigment for baby powder. ZnO has a potential to use as light emitter for life science and medical field. However, it needs ultraviolet light excitation due to the wide band gap. This absorption property limits the medical use. We tried to extend the excitation wavelength range to visible light filed by attaching Au nanoparticle, which has plasmon absorption at visible wavelength range. We made Au supported ZnO particles as following. ZnO particles dispersed from pH 9 to pH 10 preset aqueous solution and added HAuCl4 aqueous solution. The solution was irradiated by 365 nm light or heated at 70°C under stirring for preset timeinterval. The prepared particles were characterized by a particle size, particle morphology, and light emission spectrum.