Direct ambient photopatterning of RGB quantum dots for light-emitting diodes with EQE exceeding 20%

Optical patterning of quantum dots is essential for the fabrication of light-emitting diodes displays. However, current patterning methods either require inert environments or compromised quantum dots optical properties under ambient conditions. Here, we report a photoresist-free strategy enabling direct quantum dot patterning in air by using triphenylphosphine, a cost-effective, commercially available molecule that functions simultaneously as a surface ligand, photoinitiator, and oxidation protector. Under light exposure, triphenylphosphine reacts with atmospheric oxygen to trigger solubility changes, allowing precise patterning with resolutions up to 9534 dpi. The resulting devices exhibit external quantum efficiencies of 21.6% (blue), 25.6% (green), and 20.2% (red). We further demonstrate full-color active-matrix quantum dots light-emitting diodes displays by integrating the patterned red, green and blue quantum dots with thin-film transistor backplanes. This work offers a scalable, non-destructive, and environmentally compatible patterning solution for industrial display technologies.