Cost-effective, high-throughput industrial applications of metal halide perovskites in large-area displays are hampered by the fundamental difficulty of controlling the process of polycrystalline film formation from precursors, which results in the random growth of crystals, leading to non-uniform large grains and thus low electroluminescence efficiency in large-area perovskite light-emitting diodes (PeLEDs). Here we report that highly efficient large-area PeLEDs with high uniformity can be realized through the use of colloidal perovskite nanocrystals (PNCs), decoupling the crystallization of perovskites from film formation. PNCs were precrystallized and surrounded by organic ligands, and thus they were not affected by the film formation process, in which a simple modified bar-coating method facilitated the evaporation of residual solvent to provide uniform large-area films. PeLEDs incorporating the uniform bar-coated PNC films achieved an external quantum efficiency (EQE) of 23.26% for a pixel size of 4 mm² and an EQE of 22.5% for a large pixel area of 102 mm² with high reproducibility. This method provides a promising approach towards the development of large-scale industrial displays and solid-state lighting using perovskite emitters.

金属卤化物钙钛矿在大面积显示器中的成本效益、高通量工业应用受到控制前驱体形成多晶薄膜过程的根本困难的阻碍，这导致晶体的随机生长，导致大面积不均匀。晶粒和因此大面积钙钛矿发光二极管（PeLED）中的低电致发光效率。在这里，我们报告了通过使用胶体钙钛矿纳米晶体 (PNC) 可以实现具有高均匀性的高效大面积 PeLED，从而将钙钛矿的结晶与成膜分离。PNCs预结晶并被有机配体包围，因此它们不受成膜过程的影响，其中一种简单的改进的棒涂法促进了残留溶剂的蒸发，从而提供了均匀的大面积薄膜。采用均匀条形涂层 PNC 薄膜的 PeLED 在 4 mm 像素尺寸下实现了 23.26% 的外部量子效率 (EQE)²和 22.5% 的 EQE 对于 102 mm ²的大像素区域具有高再现性。该方法为使用钙钛矿发射器开发大型工业显示器和固态照明提供了一种有前途的方法。