Asymmetric Wettability Interfaces Induced a Large-Area Quantum Dot Microstructure toward High-Resolution Quantum Dot Light-Emitting Diodes.

Precisely patterning large-area quantum dot (QD) nanoparticles is an essential technique for enhancing high-resolution and high-performance in the next-generation display-QLEDs. However, conventional solution-based assembly techniques suffer from trade-offs between large-scale and spatial precision. As such, large nondefect areas and ordered stacking of QD assembly architectures are difficult to achieve, and both are essential to fabricating a high-performance device. Herein, we demonstrate a facile method for assembling the QD nanoparticles into a microstructure using an asymmetric wettability template to regulate the dewetting process. The wettability difference of the interface induces the continuous liquid film to recede into individual liquid bridges, which enabled unidirectional dewetting and regulated the QD solution mass transport. In addition, because of the asymmetric wettability between the substrate and template, large-scale, ultrafine (1 μm), and highly flat microwire QD arrays with the precise position and strict alignment are easily assembled and transferred onto the target substrate. The method has been further introduced into the fabrication of high-resolution patterned QLED devices, with maximum electroluminescence values of 73 490, 4357, and 950 cd/m2 for green, red, and blue, respectively. This research provides a novel and facile perspective for manufacturing high-resolution and high-performance patterned QLED devices.