Highly stable, sensitive, and wide-range temperature sensing of luminous nanofibers fabricated by in-situ crystallization of CsPbBr₃ within silica for a non-contact optical temperature probe

Non-contact thermometry has been proved a promising technique for temperature sensing and monitoring in biological systems, running turbine blades, operating bearings, mechanical or electrical devices. Herein, we developed a one-step electrospinning technique to fabricate rarely reported CsPbX₃@SiO₂ nanofibers (CsPbX₃@SNFs) via in-situ crystallization perovskite CsPbX₃ nanocrystals (NCs) inside silica nanofibers (SNFs) that provided excellent encapsulation of NCs by silica, and excellent temperature-dependence for non-contact temperature probes. The fabricated CsPbBr₃@SNFs featured well-dispersed CsPbBr₃ nanocrystals (∼5–6 nm) within the SNFs (∼200–500 nm), higher photoluminescence quantum yields (>60 %), and readily tunable emission wavelengths by simple variation of halide compositions. Additionally, due to effective protection from silica, CsPbBr₃@SNFs had improved stabilities towards heat, UV irradiation, and air, and preserved their remarkable optical performance. Moreover, the CsPbBr₃@SNFs presented excellent temperature-dependency towards PL intensity, a wide temperature-response range (303–473 K), and temperature-dependent reversibility (>10 heating/cooling cycles), which confirmed its potential for application as a stable and sensitive non-contact temperature probe. This paper provides a novel strategy for fabricating robust luminous perovskites with environmental stability, while greatly broadening the photoelectric applications of perovskites, especially for non-contact temperature probes.