Efficient Copper Iodide Cluster‐Based Light‐Emitting Diodes Enabled by Dual‐Anchoring Self‐Assembled Monolayers

Vapor-deposited light-emitting diodes (LEDs) based on non-toxic copper-iodide nanoclusters (Cu NCs) hold immense potential for scalable solid-state lighting and displays. However, interface defects-induced device performance degradation remains a critical challenge for organic-inorganic nanoclusters. Here, we present an interfacial coordinate-bond passivation strategy employing a pyridine-functionalized self-assembled monolayer (SAM) material featuring tailored pyridine anchoring groups. The designed pyridine-functionalized SAM materials simultaneously passivate the Cu NCs emissive layer (EML) and optimize charge injections. Consequently, we demonstrate Cu NCs-based LEDs achieving a peak external quantum efficiency (EQE) of 22.5%, a maximum luminance of 41 432 cd∙m^-2, and an improved operating half-lifetime of 119 h at 1000 cd∙m^-2, which is among the best of reported vapor-deposited clusters-based LEDs. Moreover, we demonstrate active-matrix displays by integrating Cu NCs-based LEDs onto drive circuits. This work highlights the critical role of molecularly engineered SAMs in unlocking the high-performance cluster-based LEDs.