Construction of anisotropic re-shaping mechanism of gold crystals with self-assembling surfactants

2017 Fiscal Year Final Research Report

• Project/Area Number: 16K12634
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Environmental conscious materials and recycle
• Research Institution: Ochanomizu University
• Principal Investigator: Imura Clara お茶の水女子大学, 基幹研究院, 講師 (60707107)
• Co-Investigator(Renkei-kenkyūsha): IMURA Yoshiro 東京理科大学, 工学部工業化学科, 助教 (70756288) ; SHINDO Hitoshi 中央大学, 理工学部応用化学科, 教授 (90245986)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Keywords: ナノ結晶 / 金 / 界面活性剤 / 形態制御

Outline of Final Research Achievements

Shape-control of gold crystals is important because their properties strongly depend on the structures and the sizes. In this work, anisotropic-re-shaping of gold crystals are investigated for the sustainable use of the catalytic applications.
First, micro-sized tabular gold crystals were prepared by reduction of HAuCl4 in the presence of a long chain amidoamine derivative. Reshaping of the gold crystals was approached by adding CTAB/HAuCl4 mixture. At the initial stage, the tabular crystals were etched by Br- and were changed into granular crystals. In the later stage, however, the etched crystals were reshaped into rod crystals having {211} and {110} facets due to surface selective adsorption of CTAB micelles. The rod crystals grew along the <111> direction. AFM and SAED observation revealed that anisotropic growth was caused by the changes in stabilities of gold crystal facets using the surfactant.

Free Research Field

コロイド界面化学、資源循環