An accessible visible-light actinometer for the determination of photon flux and optical pathlength in flow photo microreactors
An accessible visible-light actinometer for the determination of photon flux and optical pathlength in flow photo microreactors
复制标题
一种易于使用的可见光光光计，用于测定流式光微反应器中的光子通量和光程长度
作者：
Anca Roibu;Senne Fransen;M. E. Leblebici;G. Meir;T. Van Gerven;S. Kuhn
光化学与流动微反应器的耦合使得与批处理系统相比具有更高效率的新型合成策略成为可能。提高光化学反应机制的再现性和理解需要定量工具，如化学光化测量。然而，可应用于微反应器中的光化系统的选择是有限的，由于它们的短光程长度与大的接收光子通量的组合。此外，用于表征由500至600 nm之间的可见光驱动的反应（例如光敏氧化）的日射计在很大程度上缺失。在本文中，我们提出了一种新的可见光光度计，它可以应用于流动微反应器在480和620 nm之间。该光度计系统基于二芳基乙烯衍生物从封闭形式到开放形式的光异构化反应。用于光化测量的实验协议是容易的，其特征在于具有良好的再现性，我们还提出了一个分析估计来计算光子通量。此外，我们提出了一种实验方法来确定微反应器中的平均路径长度，使用光度测量。在使用流动微反应器进行光化学反应的研究兴趣越来越大的背景下，建议的可见光辐射计有利于确定在受限的几何形状中接收的光子通量和平均路径长度。
Coupling photochemistry with flow microreactors enables novel synthesis strategies with higher efficiencies compared to batch systems. Improving the reproducibility and understanding of the photochemical reaction mechanisms requires quantitative tools such as chemical actinometry. However, the choice of actinometric systems which can be applied in microreactors is limited, due to their short optical pathlength in combination with a large received photon flux. Furthermore, actinometers for the characterization of reactions driven by visible light between 500 and 600 nm (e.g. photosensitized oxidations) are largely missing. In this paper, we propose a new visible-light actinometer which can be applied in flow microreactors between 480 and 620 nm. This actinometric system is based on the photoisomerization reaction of a diarylethene derivative from its closed to the open form. The experimental protocol for actinometric measurements is facile and characterized by excellent reproducibility and we also present an analytical estimation to calculate the photon flux. Furthermore, we propose an experimental methodology to determine the average pathlength in microreactors using actinometric measurements. In the context of a growing research interest on using flow microreactors for photochemical reactions, the proposed visible-light actinometer facilitates the determination of the received photon flux and average pathlength in confined geometries.
影响因子：
5.2
作者：
Neumann, Matthias;Zeitler, Kirsten
通讯作者：
Zeitler, Kirsten