Ag-O-Co Interface Modulation-Amplified Luminol Cathodic Electrogenerated Chemiluminescence

Area of Science:

• Electrochemistry
• Materials Science
• Chemical Sensing

Background:

• Improving cathodic electrogenerated chemiluminescence (ECL) in luminol-dissolved oxygen systems is challenging.
• Interface modulation of metal-support interactions is a promising strategy for enhancing oxygen reduction reaction (ORR) activity.
• Designing electrocatalysts with modulated interfaces can amplify ECL involving reactive oxygen species (ROSs).

Purpose of the Study:

• To fabricate and investigate a novel single-atom catalyst for enhanced cathodic ECL.
• To explore the role of interface engineering in improving ECL performance.
• To understand the mechanism behind ECL enhancement in a luminol-dissolved oxygen system.

Main Methods:

• Fabrication of a silver single-atom catalyst with an oxygen-bridged interface (Ag-O-Co) on a CoAl layered double hydroxide (LDH) modified ITO electrode (Ag^s/LDH/ITO) via electrodeposition.
• Electrochemical characterization of the fabricated electrode.
• Evaluation of the cathodic ECL intensity of the luminol-dissolved O₂ system using the Ag^s/LDH/ITO electrode and comparison with control electrodes.

Main Results:

• The Ag^s/LDH/ITO electrode exhibited extraordinarily enhanced cathodic ECL intensity compared to bare ITO and Ag nanoparticle electrodes.
• The enhanced ECL was attributed to increased ROSs generation via electrocatalytic ORR at the Ag-O-Co interface.
• Electron redistribution at the Ag-Co bimetallic sites accelerated electron transfer, O₂ adsorption, and activation through a four-electron pathway.

Conclusions:

• The fabricated Ag single-atom catalyst with an oxygen-bridged interface significantly improves luminol cathodic ECL.
• Interface engineering is a viable strategy for developing advanced electrocatalysts for ECL applications.
• This work provides insights into metal-support interface effects and opens new avenues for ECL amplification.