▎ 摘　　要

NOVELTY - Preparing poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) composite film with controllable fluorescent comprises (i) mixing P(VDF-TrFE) powder and rare earth ion co-doped β-sodium yttrium fluoride nanoparticles and dissolving in an organic solvent to form a uniform solution, (ii) dropping obtained uniform solution on the substrate, and spin-coating to form a film, and (iii) vacuum annealing on the spin-coated sample. USE - The thin film is used in multifunctional sensors e.g. optical sensor device (claimed). ADVANTAGE - The thin film realizes the selective enhancement of light emission of rare earth ions, and can change the light intensity by adjusting the orientation degree of the thin film, and realizes the coupling of force, electricity and light, and has important application prospects. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a P(VDF-TrFE) composite film with controllable fluorescent prepared by the method, where in the thin film, the rare earth ion co-doped β-sodium yttrium fluoride nanoparticles are attached to the surface of the P(VDF-TrFE) sheet crystal.