Ambient Direct Lithography Patterning of Ultra‐Stable Perovskite Quantum Dots for High‐Resolution Light‐Emitting Diodes

Abstract

Abstract Direct lithography enables precise micro‐scale patterning of perovskite quantum dots (PQDs), which is essential for realizing high‐resolution PQD light‐emitting diodes (PQD‐LEDs). However, achieving PQDs patterning under ambient conditions is challenging due to the sensitivity of PQDs to ambient environments, high doses of UV light, and light‐generated side reactions during photolithography processes. Moreover, existing photosensitive ligands used in the direct lithography process can hardly achieve both good conductivity and satisfactory dispersibility of PQDs. To overcome these limitations, a versatile dual‐ligand (vinyl phosphonic acid, VPA; 1,10‐decanedithiol, DE) passivation strategy is engineered to realize high photosensitivity, dispersion, and stability of PQDs (referred to as PQDs/VPA‐DE) under ambient conditions. This innovative approach resulted in PQDs/VPA‐DE with a high PLQY of up to 97.6%, compared to only 58.6% for pristine PQDs. Moreover, high‐resolution (4233 pixels per inch, PPI), high‐fidelity (approaching 99%), and multi‐color (RGB) PQDs/VPA‐DE pixels under ambient conditions are successfully fabricated. Furthermore, the feasibility of assembling high‐resolution PQD/VPA‐DE‐LEDs is demonstrated using PQDs/VPA‐DE pixels (1707 PPI) prepared under ambient conditions, with an EQE of 13.09% and a luminance of 29968 cd m −2 , which is one of the highest values for high‐resolution PQD‐LEDs assembled under ambient conditions.