Moradi Maryam, Staude Isabelle, Pertsch Thomas, Jäger Michael, Schubert Ulrich S
Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstraße 10, 07743, Jena, Germany.
Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743, Jena, Germany.
Nanoscale. 2022 Sep 2;14(34):12395-12402. doi: 10.1039/d2nr02654f.
The control of plasmon-nanoemitter interactions at the nanoscale enables the tailored modulation of optical properties, namely, the photoluminescence (PL) intensity of the nanoemitters. In this contribution, using a nanometer-thick poly[(2-diethylamino) ethyl methacrylate] (39 to 74 nm) as pH responsive spacer layer (p ∼ 6 to 6.5) between a plasmonic gold film and CdSe/ZnS Quantum Dots (QDs) nanoemitters, we could achieve reversible pH-responsive PL switching in QDs. In fact, the swelling (at pH 5) and shrinking (at pH 11) function of the pH-responsive spacer layer modulates the distance between the QDs and the gold surface, which dictates the plasmonic film-QDs nanoemitter interaction. Notably, we observed a high QDs' PL enhancement of up to a factor of 3.1 ± 0.4 through changing the pH value from 5 to 11. Furthermore, based on a systematic analysis of several samples with different spacer layer thicknesses and multiple pH cycles, our developed system revealed substantial stability, reversibility and PL enhancement reproducibility. Thus, the established acid-base responsive switchable systems may represent an appealing platform for applications such as sensors, biochemical assays, optoelectronics and logic gates and can be easily evolved to other multifunctional switchable systems using alternative stimuli-responsive polymers.
在纳米尺度上控制等离子体-纳米发射体相互作用能够实现对光学性质的定制调制，即纳米发射体的光致发光（PL）强度。在本论文中，我们使用纳米厚的聚[（2-二乙氨基）乙基甲基丙烯酸酯]（39至74纳米）作为等离子体金膜与CdSe/ZnS量子点（QD）纳米发射体之间的pH响应间隔层（p ∼ 6至6.5），实现了量子点中可逆的pH响应PL开关。事实上，pH响应间隔层的膨胀（在pH 5时）和收缩（在pH 11时）功能调节了量子点与金表面之间的距离，这决定了等离子体膜-量子点纳米发射体的相互作用。值得注意的是，通过将pH值从5改变到11，我们观察到量子点的PL增强高达3.1 ± 0.4倍。此外，基于对几个具有不同间隔层厚度的样品和多个pH循环的系统分析，我们开发的系统显示出显著的稳定性、可逆性和PL增强再现性。因此，所建立的酸碱响应可切换系统可能代表了一个有吸引力的平台，可用于传感器、生化分析、光电子学和逻辑门等应用，并且可以很容易地使用替代的刺激响应聚合物演变为其他多功能可切换系统。
