Dual-enhanced electrochemiluminescence of Au nanoclusters: Ag doping-induced emission and Ce-MOFs-induced excitation.

The enhancement of electrochemiluminescence (ECL) efficiency in Au nanoclusters (AuNCs) represents a crucial strategy for expanding the application scope of AuNCs in ECL field. However, current research efforts primarily focus on enhancing the ECL efficiency of AuNCs merely from either an emission or excitation perspective. Herein, the present work commenced by considering the roles of the ECL probe and co-reactant, respectively, to develop a dual-enhanced ECL system with the simultaneous enhancement in emission and excitation. Specifically, starting from the perspective of the ECL probe, Ag was doped into AuNCs to prepare Au-Ag bimetallic nanoclusters (AuAgBNCs). On the one hand, the formation of Au-Ag alloy in the core layer exhibited a synergistic effect in enhancing ECL, and on the other hand, the formation of Ag-N bonds in the shell layer restricted the free movement of surface ligands. These two interactions collectively improved the emission efficiency of AuNCs. Concurrently, porous and dendritic Ce-MOFs were introduced as co-reaction accelerator to facilitate the production of triethylamine radicals (TEA) and excited state AuAgBNCs (AuAgBNCs∗), thereby improving the efficiency of the ECL system from the perspective of excitation. Ultimately, based on the dual-enhanced ECL system, a molecularly imprinted polymer-ECL (MIP-ECL) sensor was developed to detect diuron. This study opened new horizons for the creation of metal nanoclusters with superior ECL efficiency from both emission and excitation perspectives.