Electrochemically Lighting Up Luminophores at Similar Low Triggering Potentials with Mechanistic Insights

Abstract

Electrochemiluminescence (ECL) with high electrode compatibility and less electrochemical interference has conventionally been envisioned by lowering the oxidative potential of luminophores and/or screening luminophores with a low oxidative potential. Herein, an alternative was developed by employing the environmental-friendly carbohydrazide as a coreactant, which enabled serial luminophores with oxidative-reduction ECL at one similar low triggering potential around 0.55 V versus Ag/AgCl, including Ru­(bpy)3 2+ as well as CdTe, CdSe, CuInS2/ZnS, and Au nanocrystals. Because the eight-electron releasing process of carbohydrazide was electrochemically triggered at ∼0.25 V versus Ag/AgCl, the radicals generated via electrochemical oxidation of carbohydrazide could reduce the luminophores at a much lower potential than those of traditional coreactants. All the luminophore/carbohydrazide systems exhibited one ECL process around 0.55 V, which was about 0.65 V lower than that of a traditional Ru­(bpy)3 2+/tri-n-propylamine system (typically around +1.2 V), and even lower than the oxidative potential of some luminophores. The ECL of the luminophore/carbohydrazide system was spectrally close to that of the corresponding luminophore/tri-n-propylamine system; the maximum emission wavelength of the low triggering potential ECL could shift from 540 to 783 nm via the selection of luminophores in this case. The coreactant screening strategy would be a favorable addition to the expected luminophore screening strategy for achieving enhanced ECL performance. This work created an avenue toward a deeper understanding of the ECL mechanism.

Electrochemistry and Electrochemiluminescence of Coumarin Derivative Microrods: Mechanism Insights

“…It can be seen from the comparison of CV curves in Figure A and ECL curves in Figure B that a cathodic ECL emission onset potential of around −1.40 V was more negative than the reduction potential of K 2 S 2 O 8 , indicating that the cathodic ECL-triggering potential is determined by the electron-injection potential of C545T MRs. Although the ECL of C545T MRs/GCE was observed at both anode and cathode regions in the presence of coreactants, quite negative potential-triggering cathodic ECL emission was highly susceptible to electrochemical interference . Therefore, the anode ECL of C545T MRs is the focus of this work.…”

Progress in spectrum-based electrochemiluminescence quantitative analysis

“…Long等 [97] . Fu等以水合肼为共反应剂 实现了CIS/ZnS量子点在0.55 V附近的ECL辐射 [98] , 有 效降低了CIS/ZnS量子点ECL发光电位和电化学干扰; 以碳酰肼为共反应剂进一步实现了多种ECL物质在 0.55 V附近的低电位ECL辐射 [99] , 为低电位单波段 ECL体系的研发提供了新思路.…”

Photonic Crystal of Polystyrene Nanomembrane: Signal Amplification and Low Triggered Potential Electrochemiluminescence for Tetracycline Detection

“…For example, the oligonucleotide sequence will be damaged at a voltage of +1.0 V. 8,11 Therefore, it is very desirable to construct a low excitation potential ECL system. At present, low excitation potential ECL was usually achieved by screening luminophores with low oxidation potential, matching low potential co-reaction reagents, 8,9,12 and designing ingenious electrode structures. 13 Habtamu et al 13 constructed a low excitation potential ECL system based on a membrane-templated gold nanoelectrode, which can be used in common reaction ECL.…”