<p>Cerium-doped terbium phosphate nanowires (Ce-TbPO₄ NWs) were synthesized as an electrochemiluminescence (ECL) emitter. The ECL intensity of Ce-TbPO₄ was enhanced using a dual-sensitization strategy of energy transfer from Ce³⁺ to Tb³⁺ and the antenna effect of the ligand. Copper metal-organic framework (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene hydrate, Cu₃(HHTP)₂) electrocatalyst and silver nanoparticle (AgNP) were used as co-reaction promoters to construct ECL immunosensors for detecting interleukin-6 (IL-6). In addition, the use of H₂O₂ as an additional co-reaction promoter synergistically amplified the cathodic ECL responses. The developed immunosensor exhibited excellent sensitivity for IL-6 detection in a linear range of 10&#xa0;fg·mL^‒1 – 100 ng·mL^‒1 with a detection limit of 2.0&#xa0;fg·mL^‒1. This study establishes a new paradigm for signal amplification of multiple strategies to enhance the intensity of ECL and offers insight into the construction of immunosensors for the early diagnosis of diseases.</p> Graphical abstract <p></p>