Polymer-Mediated In Situ Growth of Perovskite Nanocrystals in Electrospinning: Design of Composite Nanofiber-Based Highly Efficient Luminescent Solar Concentrators

Lead halide perovskite nanocrystals have emerged as core materials for next-generation optoelectronics because of their high quantum yield, tunable band gaps, and facile mass production based on solution processes. Conventional perovskite luminescent solar concentrators (LSCs) are prepared using nanocrystal/polymer composite films. They require a multistep fabrication process, including the presynthesis of nanocrystals and deposition of nanocrystal–polymer mixed solutions under controlled rheological parameters. Herein, we introduce highly efficient perovskite LSCs designed with electrospun perovskite/polymer composite nanofibers. Methylammonium lead bromide (MAPbBr3) nanocrystals were synthesized via a polymer-mediated in situ growth process during electrospinning. The annealing-free and one-step fabricated luminescent composite nanofiber mats exhibited excellent photoluminescence characteristics. The light absorption, transmittance, and optical haze of the nanofiber mats were further improved after poly(methyl methacrylate) (PMMA) layers were deposited. Nanofiber mats passivated with PMMA were used as an LSC film, exhibiting impressive optical efficiencies of 11.18% for geometry (G) factors of 2.77. The corresponding PCE of the Si solar cells coupled with LSC was 2.35%. This value was almost retained under continuous 1 sun illumination for 120 h. The LSCs also demonstrate their great potential in indoor environments, as they exhibit an excellent PCE of 5.3% under a white light illuminance of 1000 lx.