Full-Color Fiber Light-Emitting Diodes Based on Perovskite Quantum Wire Arrays

Fiber light-emitting diode (Fi-LED), which can be used for wearable lighting and display devices, is one of the key components for fiber/textile electronics. However, there exists a number of impediments to overcome on device fabrication with fiber-like substrates, such as gravity and surface tension-induced non-uniform coating, low-quality crystallization, complex process for electrode deposition, etc., which culminate in uneven and inefficient light emission. Here, we uniformly grew all-inorganic perovskite quantum wire (PeQW) arrays by filling high-density alumina nanopores on the surface of aluminum (Al) fibers with a dip-coating process. The obtained PeQWs exhibit a prominent photoluminescence quantum yield (PLQY) of nearly 90% and a noticeable photoluminescence (PL) lifetime (T_PL50) of up to 1,500 hours under ambient condition. With a 2-step evaporation method to coat a surrounding transporting layer and semi-transparent electrode, we successfully fabricated full-color Fi-LEDs with emission peaks at 625 nm (red), 512 nm (green), and 490 nm (sky-blue), respectively. Intriguingly, additional polydimethylsiloxane packaging helps instill the mechanical bendability, stretchability, and waterproof feature of Fi-LEDs. The plasticity of Al fiber also allows the one-dimensional architecture Fi-LED to be shaped and constructed for two-dimensional or even three-dimensional architectures, opening up a new vista for novel lighting with unconventional formfactors.