Cu2O Nanocrystal-Templated Growth of Cu2S Nanocages with Encapsulated Au Nanoparticles and In-Situ Transmission X-ray Microscopy Study
Cu2O Nanocrystal-Templated Growth of Cu2S Nanocages with Encapsulated Au Nanoparticles and In-Situ Transmission X-ray Microscopy Study
复制标题
DOI：
10.1002/adfm.201002108
复制
发表时间：
2011-02-22
影响因子：
19
通讯作者：
Huang, Michael H.
中科院分区：
文献类型：
--
作者：
Kuo, Chun-Hong;Chu, Yi-Ting;Huang, Michael H.
立方和八面体Cu 2 O纳米晶和Au-Cu 2 O核壳异质结构被用作生长Cu 2S纳米笼和Au-Cu 2S核笼结构的牺牲模板。一个快速的硫化过程，涉及的表面反应的Cu 2 O纳米晶体与Na 2S，然后通过蚀刻的Cu 2 O核心与HCl溶液约5秒，结果在制造的Cu 2S笼的壁厚为10-20 nm。透射电子显微镜表征揭示了结晶壁的形成和存在的超小孔的尺寸为1 nm或less. Formation的Cu 2 O-Cu 2S核壳结构和它们转化成Cu 2S笼的UV-vis吸收光谱验证。X射线光电子能谱进一步证实了笼的组成为Cu 2S。通过Kirkendall效应的整个挖空过程使用原位透射X射线显微镜记录。壳形成后，连续的离子扩散除去内部的Cu 2 O。观察到中间结构与剩余的中央Cu 2 O部分和桥接臂周围的笼子里。纳米笼还显示允许分子运输：蒽和芘渗透到笼中导致增强的荧光淬灭后立即吸附到封装的金纳米晶体的表面上。
Cubic and octahedral Cu2O nanocrystals and Au-Cu2O core-shell heterostructures are used as sacrificial templates for the growth of Cu2S nanocages and Au-Cu2S core-cage structures. A rapid sulfidation process involving a surface reaction of Cu2O nanocrystals with Na2S, followed by etching of the Cu2O cores with HCl solution for approximate to 5 sec, results in the fabrication of Cu2S cages with a wall thickness of 10-20 nm. Transmission electron microscopy characterization reveals the formation of crystalline walls and the presence of ultrasmall pores with sizes of 1 nm or less. Formation of Cu2O-Cu2S core-shell structures and their conversion into Cu2S cages is verified by UV-vis absorption spectroscopy. X-ray photoelectron spectra further confirm the composition of the cages as Cu2S. The entire hollowing process via the Kirkendall effect is recorded using in-situ transmission X-ray microscopy. After shell formation, continuous ionic diffusion removes the interior Cu2O. Intermediate structures with remaining central Cu2O portions and bridging arms to the surrounding cages are observed. The nanocages are also shown to allow molecular transport: anthracene and pyrene penetration into the cages leads to enhanced fluorescence quenching immediately upon adsorption onto the surfaces of the encapsulated gold nanocrystals.