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

ABSTRACT 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.