posted on 2022-01-05, 19:04authored byTing Jiang, Jiaqi Wang, Lingling Xie, Congcong Bai, Min Wang, Yafeng Wu, Fang Zhang, Yang Zhao, Bingkun Chen, Yongtian Wang
Polarized emissive materials with
anisotropic nanostructures have
attracted tremendous attention as potential substitutes for polarizers.
Herein, the electrospinning technique is adopted to realize in situ
fabrication of lead-free halide Cs3Cu2I5 nanostructures embedded in poly(vinylidene fluoride) (PVDF)
micro/nanofiber films for polarized luminescence generation, with
a photoluminescence quantum yield (PLQY) of 33.3–86.1%. The
functionality of the polymer PVDF as a protector and its interactions
with Cs3Cu2I5 were demonstrated.
The Cs3Cu2I5/PVDF composite nanofibers
exhibit a higher degree of PL polarization ratio (P) than that of composite microfibers, reaching a highest P of 0.4 and long-term stability. This polarized emission
is attributed to the directional transition dipole moment (TDM) induced
by the asymmetric crystal structure of aligned Cs3Cu2I5 nanorods and dielectric confinement effect of
the PVDF matrix. The universality of the in situ electrospinning preparation
strategy is confirmed by the fabrication of a Cs3Cu2I5/PVA fiber film with a P of
0.5. The reported Cs3Cu2I5/polymer
nanofiber films with bright and highly polarized light emissions will
have great potential for optoelectronic applications such as liquid
crystal display (LCD) backlighting, spectrum splitting, waveguides,
lasers, and polarized photodetectors.