Department of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.
Phys Chem Chem Phys. 2011 Sep 7;13(33):14823-30. doi: 10.1039/c1cp20643e. Epub 2011 Jul 21.
Au nano-particles were synthesized via a reductive reaction in ionic liquid solution containing Au(3+) ions using a low-energy electron irradiation technique. In this study, we focused on how the electron beam conditions (acceleration energy, beam current and irradiation time) and the kinds of ionic liquid affected the size and shape of the prepared Au particles. The sizes of the primary particles increased with higher acceleration energy of the electron beam, whereas they did not depend so much on the beam current. Although the amount of secondary particles increased with longer irradiation time, the sizes of the primary particles remained constant. The anion of the ionic liquid strongly affected the size and shape of the primary particles, which was due to the different local structure of the ionic liquid around the Au particles. When the thickness of the ionic liquid layer was smaller than the penetration length of the electron beam, the formation of secondary particles was suppressed. The present results gave an important knowledge for controlling the size and shape of the metal particles, which is important for application of various catalyst or devices.
采用低能电子辐照技术，在含有 Au(3+)离子的离子液体溶液中通过还原反应合成了 Au 纳米粒子。在本研究中，我们重点研究了电子束条件（加速能量、束流和辐照时间）和离子液体的种类如何影响所制备的 Au 颗粒的尺寸和形状。初级颗粒的尺寸随电子束的加速能量增加而增大，而对束流的依赖性则不那么大。虽然随着辐照时间的延长，次级颗粒的数量增加，但初级颗粒的尺寸保持不变。离子液体的阴离子强烈影响初级颗粒的尺寸和形状，这是由于 Au 颗粒周围离子液体的局部结构不同所致。当离子液体层的厚度小于电子束的穿透长度时，次级颗粒的形成受到抑制。本研究结果为控制金属颗粒的尺寸和形状提供了重要的知识，这对于各种催化剂或器件的应用非常重要。
