Elevating sensing capability via dual-atom catalysts boosted luminol cathodic electrochemiluminescence

The advancement of highly sensitive electrochemiluminescence (ECL) biosensors has garnered escalating interest over time. Owing to the distinctive physicochemical attributes, the signal amplification strategy facilitated by functional nanomaterials has achieved notable milestones. Single-atom catalysts (SACs), featuring atomically dispersed metal active sites, have garnered significant attention. SACs offer unprecedented control over active sites and surface structures at the atomic level. However, to fully harness their potential, ongoing efforts focus on strategies to enhance the catalytic performance of SACs, profoundly influencing both the sensitivity and selectivity of SACs-based sensing platforms.

In this study, we focused on the synthesis and application of Fe-Co-PNC dual-atom catalysts (DACs) with the incorporation of phosphorus, aiming to enhance catalytic efficiency, particularly in the context of the oxygen reduction reaction (ORR) correlated cathodic luminol ECL. The synergistic effects arising from the combination of Fe and Co in DACs were explored by ECL emission. Comparative studies with Fe-PNC SACs highlighted the superior catalytic performance of Fe-Co-PNC DACs. The ECL sensing platform exhibited excellent sensitivity, which provided a fast detection of Trolox with a wide linear range (0.1 μM-1.0 mM) and a low detection limit (LOD) of 0.03 μM. The platform demonstrated remarkable reproducibility and long-term stability, showcasing its potential for practical biosensing applications.

This study introduced the novel concept of Fe-Co-PNC DACs. The demonstrated synergistic effects and enhanced catalytic efficiency of DACs offer new avenues for the rational design of advanced catalysts. The successful application in the sensitive detection of Trolox emphasizes their potential significance in biosensing. It not only expands our understanding of SACs but also opens doors for the development of efficient and stable catalysts with broader applications.