In this study, an effective oxygen vacancy (O v )-involved luminoldissolved oxygen (O 2 ) electrochemiluminescence (luminol-DO ECL) system was developed and exploited for ECL sensing applications through significant plasmon enhancement of the O v -involved weak luminol-DO ECL signals by the combined use of Cu-doped TiO 2 oxygen vacancy and a Au@SiO 2 nanomembrane. The results disclosed that the ECL response of the corresponding system could be synergistically boosted, and the plausible underlying mechanism has been discussed. Furthermore, for the first time, the developed system has been successfully applied for the highly sensitive detection of alkaline phosphatase with a low limit of detection of 0.005 U/L, with an excellent linear range from 0.005 to 10 U/L, as well as good stability and reproducibility.

Single-atom catalysts (SACs) have recently been exploited for luminol-dissolved oxygen electrochemiluminescence (ECL); however, they still suffer from low sensitivity and narrow detection range for a real sample assay. In this work, we boost markedly the ECL response of the iron SAC (Fe-SAC)-based system, for the first time, by the excitation of two-dimensional plasmons derived from the Au@SiO2 nanomembrane. The plausible mechanism of plasmon enhancement in the Fe-SAC ECL system has been discussed. The constructed Fe-SAC ECL system has been applied for the ECL detection of dopamine, hemin, and mercury (Hg2+), with pretty low limits of detection of 0.1, 0.7, and 0.13 nM and wider linear ranges of 0.001–1.0, 0.001–10, and 0.01–0.5 nM, respectively, under optimal conditions.