Uniform Core-shell SiO2@Sr2CeO4:Eu3+nanocomposites: Exploring multiple strategies towards flexible luminescent films and data security applications

The fluorescence based core-shell nanocomposites have wide range of applications in various fields, due to its high photoluminescence quantum yield, tunable emission, efficient narrow-band as well as high color purity. Thus, a fluorescent platform based intense red-emitting spherical core-shell SiO2@Sr2CeO4:Eu3+(5 mol%) nanocomposite has been designed for flexible luminescent films with exceptional light emission, forensic and anti-counterfeiting applications. The core-shell SiO2@Sr2CeO4:Eu3+(5 mol%) nanocomposites were prepared by solvothermal route. Morphological studies reveal uniform sized spherical shaped particles, without any agglomeration. The photoluminescence emission spectra enclosed intense peaks at ∼ 535, 540, 555, 585, 612, 650 and 710 nm, which were due to 5D1→7F0, 5D1→7F1, 5D1→7F2, 5D0→7F1, 5D0→7F2, 5D0→7F3 and 5D0→7F4 transitions of Eu3+ ions, respectively. The evaluated photometric properties of the prepared nanocomposites are well agreement with commercial phosphors. The latent fingerprints are established by using SiO2@Sr2CeO4:Eu3+ (5 mol%) nanocomposites. The developed fingerprints showed excellent contrast, high sensitivity and selectivity on various substrates by revealed level I–III ridge features. The developed luminescent films demonstrated its high flexibility and strong fluorescence property, due to the uniform dispersion of core-shell nanocomposite within the organic polymer matrix. Besides, the prepared core-shell nanocomposites also allow for the application of fluorescence ink. The encoded anti-counterfeiting information was difficult to decode. Therefore, aforementioned results provide a facile approach for the design and fabrication of nanocomposites with exceptional light emission, flexibility and stability, which can serve as promising materials for the multiple applications.