Electrospun Electroluminescent CsPbBr₃ Fibers—Flexible Perovskite Networks for Light-Emitting Application

Organic-inorganic and all-inorganic lead halide perovskites (APbX₃) have continuously attracted research interest and went through significant improvements towards highly efficient photovoltaic technologies. Recently, these materials were shown to have room temperature electroluminescence. Most lead-halide perovskite devices are based on thin films or quantum dots while reports on alternative morphologies – e.g. fibers – are rare. In our research, we prepared CsPbBr₃@PVP composite nanofibers by one-step electrospinning and characterized them by scanning electron microscopy, transmission electron microscopy, X-ray diffractometry, UV/vis and photoluminescence spectroscopy. We subsequently integrated the fiber mats as active layers in proof-of-concept electrically driven light emitting devices. While the concept of perovskite nanofibers is not new, to the best of our knowledge we would be the first to report on electroluminescence of such fibers. In addition, all preparations were conducted under ambient atmosphere and the perovskite precursor ink was prepared with “green” solvents (H₂O/EtOH/ionic liquid). This work could pave the way towards cost effective and flexible optoelectronic fiber- or yarn-based lead-halide perovskite devices by a facile up-scalable method.