Polymer‐Templated In Situ Growth of Centimeter‐Scale Perovskite Nanocrystal Arrays with Ultrasmall Pixel Size and High Stability

Miniaturizing the perovskite nanocrystal (PNC) pattern is critical for advancing integrated chip-level devices and next-generation displays. However, scalable fabrication of nanoscale PNC patterns remains challenging. In this study, we report a polymer-templated in situ growth strategy for fabricating centimeter-scale PNC arrays with ultrasmall pixel size and excellent environmental stability. The method involves the use of nanoimprinting soft lithography to generate crosslinked polymer arrays, and subsequent selective nucleation and growth of PNCs within the polymeric nanodomains. The PNC-loaded nanoarrays achieve a pixel resolution of 59 325 ppi. By varying the dimension of polymeric nanocylinders, the pixel size of nanoarrays can be precisely tuned from 167.8 to 64.5 nm, breaking the limit of pixel size reported so far. Furthermore, the nanoarrays exhibit exceptional stability, retaining 91.8% of their initial photoluminescence (PL) intensity after immersion in water for over 1000 h. They also preserve 86% of their initial PL intensity after 10 thermal treatment cycles between 30 and 100 °C, and nearly 100% after 6.5 h of UV light irradiation. Finally, we demonstrate the application of PNC nanoarrays as scintillators for X-ray imaging. This study presents a simple yet effective approach for the scalable production of robust perovskite nanocrystal arrays with potential in optoelectronic applications.