Single-atom boosted electrochemiluminescence via phosphorus doping of Fe–N/P–C catalysts

Single-atom catalyst (SAC), one of the most attractive catalysts in the field of energy conversion and storage, was proven as efficient accelerator for luminol-dissolved oxygen electrochemiluminescence (ECL) via the catalysis of oxygen reduction reaction (ORR). In this work, we synthesized heteroatom doping SACs of Fe–N/P–C for the catalysis of cathodic luminol ECL. The doping of P could lower the reaction energy barrier of the OH* reduction, and promote catalytic efficiency toward ORR. The formation of reactive oxygen species (ROS) during ORR triggered cathodic luminol ECL. Greatly enhanced ECL emission catalyzed by SACs proved that Fe–N/P–C exhibited higher catalytic activity to ORR compared with Fe–N–C. Since the system was highly dependent on oxygen, an ultra-sensitive detection of a typical antioxidant, ascorbic acid, was achieved with detection limit of 0.03 nM. This study provides possibility to greatly enhance the performance of ECL platform through rational tailoring of SACs via heteroatom doping. Schematic illustration of the cathodic luminol-O2 ECL catalyzed by Fe–N/P–C SACs. [Display omitted] •Heteroatom doping SACs of Fe–N/P–C were synthesized for the catalysis of cathodic luminol ECL.•The design of electrocatalysts via interface modulation provides new opportunities for the ECL amplification.•The doping of P lowered the reaction energy barrier of OH* reduction, and promote catalytic efficiency toward ORR.•An ultra-sensitive detection of ascorbic acid was achieved with detection limit of 0.03 nM.•This work shows perspective of promoting ECL efficiency and sensing performance through rational design of SACs.