Mapping the Distribution of Potential Gradient in Bipolar Electrochemical Systems through Luminol Electrochemiluminescence Imaging
Mapping the Distribution of Potential Gradient in Bipolar Electrochemical Systems through Luminol Electrochemiluminescence Imaging
复制标题
通过鲁米诺电化学发光成像绘制双极电化学系统中的电位梯度分布
DOI：
10.1021/acs.analchem.0c05397
复制
发表时间：
2021
影响因子：
7.4
通讯作者：
Inagi Shinsuke
中科院分区：
文献类型：
--
作者：
Villani Elena;Inagi Shinsuke
双极电化学被认为是合成新型功能材料的一种强有力的、可持续的电化学过程。这种电化学技术的吸引人的特征，例如双极电极（BPE）的无线性质和在放置在同一电化学电池中的多个BPE上同时驱动电化学反应的可能性，以及改变驱动电极的形状和定位的可能性，为设计反应系统提供了很大的自由度。然而，电池的几何形状显著影响BPE表面上产生的电位梯度的分布和强度，并且由于BPE的无线性质，其监测受到阻碍。在本研究中，我们提出了使用电化学发光（ECL）作为电化学成像技术，以映射不同几何形状的双极电化学电池中的电位梯度分布。所提出的方法利用鲁米诺/过氧化氢（H2 O2）系统在BPE的阳极产生的强ECL发射，当总施加电压（Etot）是足够强的，以触发电化学反应。由于鲁米诺ECL发射是相当强烈和相对稳定的，作为Etot的函数的电位分布的演变可以使用数码相机进行监测，允许在每个双极配置的电位分布曲线的说明。建议的方法是一个有价值的和可靠的方法来映射在双极电化学系统的电位梯度，可以很容易地在每一种类型的双极配置。
Bipolar electrochemistry has been regarded as a powerful and sustainable electrochemical process for the synthesis of novel functional materials. The appealing features of this electrochemical technology, such as the wireless nature of the bipolar electrode (BPE) and the possibility to drive simultaneously electrochemical reactions on multiple BPEs placed in the same electrochemical cell, together with the possibility to change the shape and positioning of the driving electrodes, give significant freedom to design reaction systems. Nevertheless, the cell geometry dramatically affects the distribution and intensity of the potential gradient generated on the BPE surface and its monitoring is hampered due to the wireless nature of the BPE. In the present study, we propose the use of electrochemiluminescence (ECL) as an electrochemical imaging technique to map the distribution of potential gradient in bipolar electrochemical cells with different geometries. The proposed approach exploits the strong ECL emission of luminol/hydrogen peroxide (H2O2) system generated at the anodic pole of the BPE, when the total applied voltage (Etot) is strong enough to trigger the electrochemical reaction. Since luminol ECL emission is rather intense and relatively stable, the evolution of the potential distribution as a function ofEtotcan be monitored using a digital camera, allowing the elucidation of the potential distribution profile in every bipolar configuration. The suggested approach represents a valuable and reliable method to map the potential gradient in bipolar electrochemical systems and can be readily employed in every type of bipolar configuration.