Ternary Heterojunction ZnS‐ZnIn₂S₄‐In₂S₃ Efficiently Catalyzes Triethylamine to Enhance Electrochemiluminescence Imaging Signals

Abstract The visualization of electrode reactions is significant for ultra sensitive detection. Traditional electrochemiluminescence (ECL) detection method can hardly visualize electrode reactions. Combining ECL imaging technology and traditional ECL detection methods can overcome the lack of visual feedback of key information in sensor construction. In contrast to cyclic voltammetry testing, applying a constant voltage to the electrode surface for ECL imaging results in a more stable signal. In this study, methionine‐stabilized gold nanoclusters (Met‐AuNCs) are used as efficient near‐infrared luminescent clusters, and triethylamine (TEA) as coreactants to construct an ECL imaging sensor for the detection of acetamiprid (ACT). The ternary heterojunction ZnS‐ZnIn₂S₄‐In₂S₃ (Z‐Z‐I) forms a stepwise electron transfer mode, facilitating the rapid generation of free radicals in TEA. Furthermore, Z‐Z‐I serves as a substrate, providing a large loading area for the DNA chain, which lays a foundation for the wide detection range. Such an ECL imaging sensor has a wide linear range (100 fm to 1 µm) and achieves a low detection limit (42 fM) for ACT detection. This study not only provides an efficient and accurate method for detecting ACT in agricultural products but also foretells the promising application of visual imaging technology in electrochemiluminescent sensors.