Un Ieng Wai, Sivan Yonatan
School of Electrical and Computer Engineering, Ben-Gurion University of the Negev, Israel.
Nanoscale. 2020 Sep 14;12(34):17821-17832. doi: 10.1039/d0nr03897k. Epub 2020 Aug 24.
Recently, there has been a growing interest in the usage of mm-scale composites of plasmonic nanoparticles for enhancing the rates of chemical reactions; the effect was shown recently to be predominantly associated with the elevated temperature caused by illumination. Here, we study the dependence of the temperature distribution on the various parameters of these samples, and provide analytic expressions for simple cases. We show that since these systems are usually designed to absorb all the incoming light, the temperature distribution in them is weakly-dependent on the illumination spectrum, pulse duration, particle shape, size and density. Thus, changes in these parameters yield at most modest quantitative changes. We also show that the temperature distribution is linearly dependent on the beam radius and the thermal conductivity of the host. Finally, we study the sensitivity of the reaction rate to these parameters as a function of the activation energy and show how it manifests itself in various previous experimental reports. These results would simplify the optimization of photocatalysis experiments, as well as of other energy-related applications based on light harvesting for heat generation.
最近，人们对用于提高化学反应速率的毫米级等离子体纳米颗粒复合材料的应用兴趣日益浓厚；最近的研究表明，这种效应主要与光照引起的温度升高有关。在这里，我们研究了温度分布对这些样品各种参数的依赖性，并给出了简单情况下的解析表达式。我们表明，由于这些系统通常设计为吸收所有入射光，因此其中的温度分布对光照光谱、脉冲持续时间、颗粒形状、尺寸和密度的依赖性较弱。因此，这些参数的变化最多只会产生适度的定量变化。我们还表明，温度分布与光束半径和主体的热导率呈线性相关。最后，我们研究了反应速率对这些参数的敏感性作为活化能的函数，并展示了它在之前各种实验报告中的表现。这些结果将简化光催化实验以及其他基于光捕获产热的能源相关应用的优化。
