Full‐Color n‐i‐p Perovskite Light‐Emitting Diodes Based on SnO2

Perovskite light‐emitting diodes (LEDs) have achieved their highest efficiency with an n‐i‐p device structure, utilizing n‐type ZnO as the electron transport layer. The exceptional device efficiency is highly dependent on the interfacial reaction between ZnO and perovskite intermediates, which promotes the formation of high‐quality perovskite films. However, achieving green and blue perovskite LEDs with this n‐i‐p device structure remains a challenge, which hinders the fabrication of full‐color perovskite LED arrays with a consistent device structure. This challenge stems from the vigorous interfacial reaction between ZnO and bromine/chlorine‐based perovskites compared to iodine‐based perovskites during the crystallization process. Here, n‐i‐p perovskite LEDs with enhanced device performance on a relatively stable n‐type SnO2 layer are demonstrated. The near‐infrared perovskite LEDs based on SnO2 reach a peak external quantum efficiency of 21.2%. More importantly, this approach enables the realization of full‐color n‐i‐p perovskite LEDs, offering significant potential for streamlining the manufacturing process of full‐color displays.