Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 100083, P. R. China.
School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
J Phys Chem B. 2022 Apr 14;126(14):2754-2760. doi: 10.1021/acs.jpcb.1c09402. Epub 2022 Apr 1.
The role of the electrostatic environment in chemical reactions has long been an important research field, but most studies have focused on the influence of external electric fields on chemical processes, while the effect from the intrinsic electrostatic charges on the solution itself has been ignored. How an electrostatic field generated by contact electrification affects the solvent environment in a chemical reaction and then the chemical reactivity is still ambiguous. Here, based on the inspiration of the droplet triboelectric nanogenerator, electrostatic interactions between a statically charged luminol droplet and the surrounding directional electrostatic field were analyzed, and we demonstrate a relationship between the sign of the luminol sample (negatively or positively charged) and its effect on the reaction reactivity. Our results show that the increased reaction activity and the enhanced chemiluminescence (CL) only occurred when the luminol droplet yields positive charges, while a negatively charged luminol, on the contrary, tends to inhibit the CL, which brings direct evidence of the charge carriers of triboelectricity being electrons at the liquid-solid interface. This work provides a strategy for electrostatically regulating CL by simply statically charging a reaction solution with a dielectric solid and also carries a cautionary message on what to consider when preparing a sample for a chemical reaction.
静电力环境在化学反应中的作用一直是一个重要的研究领域，但大多数研究都集中在外电场对化学过程的影响上，而忽略了溶液本身固有静电荷的影响。接触起电产生的静电力场如何影响化学反应中的溶剂环境，进而影响化学反应活性，目前仍不清楚。在这里，我们受液滴摩擦纳米发电机的启发，分析了带静电的鲁米诺液滴与周围定向静电场之间的静电相互作用，并演示了鲁米诺样品（带负电或带正电）的符号与其对反应活性的影响之间的关系。我们的结果表明，只有当鲁米诺液滴带正电时，反应活性才会增加，化学发光（CL）才会增强，而带负电的鲁米诺液滴则相反，往往会抑制 CL，这为摩擦电的载流子在液-固界面上是电子提供了直接证据。这项工作提供了一种通过简单地用介电固体对反应溶液进行静电充电来静电调节 CL 的策略，并就为化学反应准备样品时应考虑哪些因素发出了警告。
