Flexible hybrid perovskite nanofiber for all-inorganic perovskite solar cells

• Perovskite nanofiber film is fabricated by electrospinning. • Perovskite nanofiber film exhibits well light capture ability. • The amount of PbBr 2 affects the crystal morphologies and optical performance. • The perovskite solar cell is assembled based on the nanofiber film. Metal halides perovskite materials with their excellent light absorption coefficient, rendering perovskite solar cells (PSCs) as potential candidates for the next generation of solar cells, have been attracting worldwide attention. One-dimensional flexible perovskite nanowires/nanoroads, with appropriate aspect ratios, can reduce crystal surface defect level and allow a smooth carrier transport channel. Herein, the all-inorganic perovskite/polymer composite nanofiber membranes were fabricated via electrospinning technique. The hybrid all-inorganic perovskite nanofiber membranes possessed the characteristics of bending under force, which emerged pleasurable flexibility. The viscosity of the spinning solution and the morphology of the perovskite nanofibers were prominent affected by the concentration of PbBr 2 into the perovskite precursor solution. With the concentration of PbBr 2 increased, both the grain sizes of perovskite nanocrystals on the nanofiber membranes and the corresponding PCE of the as-assembled PSCs were gradually increased, with a champion efficiency of 2.28% for 3 mol/L PbBr 2 . This research could assist in establishing systematic research on perovskite fiber structure and expanding its application in wearable electronic devices.