In Situ Encapsulation of Ultrasmall CuO Quantum Dots with Controlled Band-Gap and Reversible Thermochromism

详细信息    查看全文

• 作者：Yuzhen Ge ; Zameer Hussain Shah ; Cui Wang ; Jiasheng Wang ; Wenxin Mao ; Shufen Zhang ; Rongwen Lu
• 刊名：ACS Applied Materials & Interfaces
• 出版年：2015
• 出版时间：December 9, 2015
• 年：2015
• 卷：7
• 期：48
• 页码：26437-26444
• 全文大小：693K
• ISSN：1944-8252

文摘

Silica encapsulated ultrasmall CuO quantum dots (QDs; CuO@SiO₂) were synthesized by reverse microemulsion. The CuO QDs with sizes ranging from 2.0 to 1.0 nm with corresponding band gaps of 1.4 to 2.6 eV were prepared simply by varying the concentration of the Cu²⁺ precursor. The samples were characterized by Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and UV鈥搗is spectroscopy. The CuO@SiO₂ composite displayed reversible thermochromism which resulted from the strong electron鈥損honon coupling of ultrasmall CuO in the confined space of SiO₂ and the enhanced band-gap shift in the visible light region depending on temperature. Besides, the as synthesized CuO@SiO₂ was found to be highly stable for reversible thermochromism due to the micropore structure of silica matrix and local confinement of the QDs.