法国波尔多大学Neso Sojic研究团队在无机化学研究中取得进展。他们提出了通过敲除金活性位点增强电化学发光。相关论文于2024年12月16日发表在《德国应用化学》杂志上。

据介绍，在传统[Ru(bpy)₃]²⁺发色团和胺基共反应物组成的系统中，电化学发光（ECL）在贵金属电极上尤为低效。这是由于在金属表面形成了钝化氧化层，抑制了三正丙胺（TPrA）等胺的电氧化。

该研究组证明了用Cu-Fenton试剂化学生成的羟基自由基，攻击增强了金表面的电化学发光（ECL）发射。这些自由基选择性地使金活性位点失活，并敲除金属表面的凹凸不平，这与直觉相反，导致ECL发射的放大。原子力显微镜显示了表面的大量平滑。电化学表征表明，所涉及的ECL反应机理由直接氧化转向催化氧化，在失活金表面促进了三正丙胺的间接氧化动力学。

此外，在串联[Ru(bpy)₃]²⁺/TPrA存在下，对粗糙电极进行原位平滑处理，ECL增强使Cu²⁺传感具有良好的可靠性和检测限。这种原子光滑和耐腐蚀的金表面很容易调整ECL的反应性，为研究外形和反应性对ECL机制的影响开辟了新的方向，对未来ECL成像策略和高灵敏度ECL传感器的发展具有重要意义。

附：英文原文

Title: Enhanced Electrochemiluminescence by Knocking Out Gold Active Sites

Author: Neso Sojic, Indhu Leka Kottaiveedu Sivakumar, Laurent Bouffier, Shanmugam Senthil Kumar

Issue&Volume: 2024-12-16

Abstract: Electrochemiluminescence (ECL) of the conventional system of [Ru(bpy)3]2+ luminophore and amine-based coreactants is particularly inefficient on noble metal electrodes. This is due to the formation of a passivating oxide layer on the metal surface inhibiting the electro-oxidation of amines like tri-n-propylamine (TPrA) coreactant, Herein, we demonstrated the enhancement of ECL emission on gold surface by hydroxyl radicals attack that are chemically generated with Cu-Fenton reagent. These radicals selectively deactivate the gold active sites and knockout the metal surface asperities that counterintuitively led to an amplification of the ECL emission. Atomic Force Microscopy shows a massive smoothening of the surface. The electrochemical characterization proves that the involved ECL reaction mechanism switches from direct oxidation to catalytic route, where the kinetics of indirect TPrA oxidation is facilitated on deactivated gold surface. Besides, in situ smoothening of a rough electrode in presence of tandem [Ru(bpy)3]2+/TPrA, the ECL enhancement enables Cu2+ sensing with good reliability and limit of detection. Such atomically smoothened and corrosion-resistant gold surface readily tuned the ECL reactivity and opened new directions on influence of topography and reactivity on ECL mechanisms, thus will be extremely useful for the future development of ECL imaging strategies and highly sensitive ECL sensors.

DOI: 10.1002/anie.202421185

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202421185