Luminescence enhancement behavior of KSr1.96Sm0.04Nb5O15/PVDF composite thick film after electric polarization

•A novel KSN-Sm/PVDF thick film with luminescent enhancement behavior was prepared.•The luminescent emission intensities of the film can be enhanced after electric polarization.•The underlying luminescence modulation mechanism has been discussed. A novel composite thick film exhibiting luminescent enhancement behavior was prepared using Sm3+ doped KSr2Nb5O15 ferroelectric microcrystals and polyvinylidene difluoride (PVDF) polymer via a tape-casting technology. After compositing with PVDF, the thick film retained the ferroelectric polarization behavior, and the PVDF phase had negligible impact on the reflectivity and optical absorption edge of ferroelectric microcrystals. The photoluminescent emission intensities of the characteristic transitions of Sm3+ exhibited significant enhancement after electric polarization, with a maximum modulation ratio exceeding 200 %. The underlying luminescence modulation mechanism is discussed. This work proposed a novel strategy for fabrication of flexible composite thick films with coupling behavior between luminescent and ferroelectric properties.