Department of Chemistry, Bar-Ilan Institute for Nanotechnology and Advanced Materials, Bar-Ilan University , Ramat-Gan 5290002, Israel.
Centre for Micro-Photonics, Swinburne University of Technology , John Street, P.O. Box 218, Hawthorn, Victoria 3122, Australia.
ACS Appl Mater Interfaces. 2017 Aug 30;9(34):28930-28938. doi: 10.1021/acsami.7b08985. Epub 2017 Aug 21.
In this manuscript, we report the refractive-index (RI) modulation of various concentrations of nitrogen-doped carbon dots (N@C-dots) embedded in poly(vinyl alcohol) (PVA) polymer. The dispersion and size distribution of N@C-dots embedded within PVA have been investigated using electron microscopy. The RI of PVA-N@C-dots can be enhanced by increasing the doping concentration of highly fluorescent C-dots (quantum yield 44%). This is demonstrated using ultraviolet-visible (UV-visible), photoluminscence, Raman, and Fourier transform infrared (FTIR) spectroscopy measurements. The Mie scattering of light on N@C-dots was applied for developing the relationship between RI tuning and absorption cross section of N@C-dots. The extinction cross section of N@C-dot thin films can be rapidly enhanced by either tuning the RI or increasing the concentration of N@C-dots. The developed method can be used as effective RI contrast for various applications such as holography creation and bioimaging.
在本文中，我们报告了嵌入聚乙烯醇（PVA）聚合物中的不同浓度氮掺杂碳点（N@C-dots）的折射率（RI）调制。使用电子显微镜研究了嵌入 PVA 中的 N@C-dots 的分散和尺寸分布。通过增加高荧光 C-dots（量子产率 44%）的掺杂浓度，可以增强 PVA-N@C-dots 的 RI。这是通过使用紫外可见（UV-可见）、光致发光、拉曼和傅里叶变换红外（FTIR）光谱测量来证明的。将光在 N@C-dots 上的米氏散射应用于开发 RI 调谐与 N@C-dots 吸收截面之间的关系。通过调节 RI 或增加 N@C-dots 的浓度，可以快速增强 N@C-dot 薄膜的消光截面。所开发的方法可用作各种应用的有效 RI 对比，例如全息图创建和生物成像。
