LAUSR

Material composition engineering and device fabrication of perovskite nanocrystals (PNCs) in solution can introduce organic contamination and entail several synthetic, processing, and stabilization steps. We report three-dimensional (3D) direct lithography of PNCs with tunable composition and bandgap in glass. The halide ion distribution was controlled at the nanoscale with ultrafast laser–induced liquid nanophase separation. The PNCs exhibit notable stability against ultraviolet irradiation, organic solution, and high temperatures (up to 250°C). Printed 3D structures in glass were used for optical storage, micro–light emitting diodes, and holographic displays. The proposed mechanisms of both PNC formation and composition tunability were verified. Description Perovskite nanocrystals under glass Perovskite nanocrystals (PNCs) such as cesium lead triiodide (CsPbI3) can display bright photoemission with narrow linewidths for display applications, but their long-term stability requires passivation and encapsulation steps after synthesis in solution. Sun et al. created three-dimensional arrays of PNCs in doped metal oxide glasses using ultrafast laser pulses that caused local melting and subsequent crystallization. They tuned the bandgap of PNCs and their photoluminescence between 480- and 700-nanometer wavelengths by transforming the composition from CsPb(Cl1-xBrx)3 to CsPbI3. These encapsulated PNCs exhibited long-term stability after prolonged heating or organic solvent and ultraviolet light exposure. —PDS Melting of a doped metal oxide glass with ultrafast laser pulses created perovskite nanocrystal arrays for optoelectronics.