Sr2GdF7: Er3+/Yb3+ nanocrystal-inlaid pliable fibers for synergistic feedback temperature monitoring

Sr2(Gd1-x-yErxYby)F7/polyacrylonitrile(SGF-EY/PAN) is fabricated with nanocrystal-inlaid fiber (NIF) structure via electrospinning, which possesses synergistic feedback and real-time temperature monitoring. Under near-infrared laser radiation, SGF-EY fibers have the advantage of more efficient upconversion luminescence, which is a viable option to achieve dual thermal feedback at specific power condition. The relative sensitivity (SR) of the principal thermal feedback (I523/I540), a significant portion to evaluate the reliability of temperature monitoring, reaches a maximal value of 0.856%K−1 at 303 K. Additionally, the peak ratio of the 523 nm green radiation influenced by two-photon absorption and the 410 nm blue radiation controlled by three-photon absorption is employed as an auxiliary indicator (I523/I410) that attains a maximum SR of 1.456%K−1 at 303 K, providing a thermal sensing with synergistic response effect. The nanocrystal-inlaid pliable fibers with dual temperature feedback suggest potential application prospects in the fields of noncontact biomedical temperature sensor, aeronautical engineering probe and flexible thermal monitoring component. Figure displays the potential application of Sr2GdF7: Er3+, Yb3+ nanocrystal-inlaid fibers (SGF-EY NIFs). The pliable SGF-EY NIFs possess excellent synergistic and real-time temperature feedback, which are expected to broaden the fields of biomedical sensor, aeronautical engineering probe and flexible component. [Display omitted] •Pliable fibers with Sr2GdF7:Er/Yb nanocrystal are is prepared via electrospinning.•The thermal response property of crystals is kept in composite fibers.•Principal and auxiliary thermal indicators realize synergistic feedback.•Nanocrystal-inlaid fibers provide perspective for optical temperature monitoring.