Large-scale planar and spherical light-emitting diodes based on arrays of perovskite quantum wires

Halide perovskites are enticing candidates for highly efficient planar light-emitting diodes (LEDs) with commercial potential in displays and lighting. However, it remains a challenge for conventional solution fabrication processes to fabricate large-scale or non-planar LEDs due to the non-uniformity of perovskite films in conjunction with material stability issues. Here large-area highly uniform arrays of crystalline perovskite quantum wires are grown with emission spectra covering the whole visible range. Photoluminescence quantum yield of up to 92% and 5,644 hours as the time for photoluminescence to degrade down to its 50% of the initial value under ambient conditions are achieved for MAPbBr₃ quantum wires. LEDs based on these quantum wires on rigid and flexible planar substrates are fabricated up to a four-inch wafer size and also unique three-dimensional spherical LEDs with outstanding uniformity are reported. The results suggest that the approach developed here can be generalized to other unconventional three-dimensional LEDs in the future.