P05 超音波とウルトラファインバブルを用いた金ナノ粒子の合成

抄録

Gold nanoparticles possess the size- and shape-dependent catalytic and optical properties. Synthesis by ultrasonic cavitation needs no surfactant and reductive agents. Ultrafine bubble (UFB) which is smaller than 1 μm in diameter has high charge on the surface and long residence time. In this study, we investigated how UFB effect the synthesis of gold nanoparticles by ultrasound. Sample was 0.1 mM HAuCl₄ solution. Ultrasonic frequency and temperature were 500 kHz and 283 K, respectively. By addition of UFB, nucleus generation time was shorten, diameter of gold nanoparticles decreased and diameter distribution of spherical particles became narrow. As the UFB density became higher, dimeter of gold nanoparticles became smaller. It is thought that UFB enhances cavitation generation and UFB attached on nanoparticles prevents aggregation of nanoparticles. As the UFB density increased, fraction of plate particles decreases. This is because formation rate of plate particles is slower than that of sphere particles.