Dual-Modal Photon Upconverting and Downshifting Emissions from Ultra-stable CsPbBr₃ Perovskite Nanocrystals Triggered by Co-Growth of Tm:NaYbF₄ Nanocrystals in Glass

Abstract

This work reports a novel dual-phase glass containing Tm:NaYbF4 upconverting nanocrystals (UCNCs) and CsPbBr3 perovskite nanocrystals (PNCs). The advantages of this kind of nanocomposite are that it provides a solid inorganic glass host for the in situ co-growth of UCNCs and PNCs, and protects PNCs against decomposition affected by the external environment. Tm:NaYbF4 NC-sensitized stable CsPbBr3 PNCs photon UC emission in PNCs is achieved under the irradiation of a 980 nm near-infrared (NIR) laser, and the mechanism is evidenced to be radiative energy transfer (ET) from Tm3+: 1G4 state to PNCs rather than nonradiative Förster resonance ET. Consequently, the decay lifetime of exciton recombination is remarkably lengthened from intrinsic nanoseconds to milliseconds since carriers in PNCs are fed from the long-lifetime Tm3+ intermediate state. Under the simultaneous excitation of the ultraviolet (UV) light and NIR laser, dual-modal photon UC and downshifting (DS) emissions from ultra-stable CsPbBr3 PNCs in the glass are observed, and the combined UC/DS emitting color can be easily altered by modifying the pumping light power. In addition, UC exciton recombination and Tm3+ 4f–4f transitions are found to be highly temperature sensitive. All these unique emissive features enable the practical applications of the developed dual-phase glass in advanced anti-counterfeit and accurate temperature detection.

Er3+/Yb3+ co‐doped oxyfluoro tellurite glasses: Analysis of optical temperature sensing based on up‐conversion luminescence

“…Therefore, the temperature can be determined by employing the FIR technique. 2,[10][11][12] [13][14][15][16][17] and crystalline materials 9,[18][19] co-doped with Er 3+ and Yb 3+ ions.…”

“…The FIR of green band transitions, 2 H 11/2 → 4 I 15/2 , and 4 S 3/2 → 4 I 15/2 depends strongly on temperature. Many authors, therefore, paid attention to UC luminescence phenomena and optical temperature sensing ability in various amorphous 13–17 and crystalline materials 9,18–19 co‐doped with Er 3+ and Yb 3+ ions.…”

Energy transfer-triggered multicolor emissions in Tb3+/Eu3+-coactivated Y2Mo3O12 negative thermal expansion microparticles for dual-channel tunable luminescent thermometers

“…Optical thermometer based on rare-earth ions activated luminescent materials has attracted much attention because of its admirable advantages including high resolution, non-contact characteristic, fast response, etc. [1][2][3] Generally, via taking the advantage of the various thermal quenching performances of two emissions originating from thermally coupled levels (i.e., TCLs) of rare-earth ions, the ratiometric thermometry is realized by utilizing the fluorescence intensity ratio (i.e., FIR) technology. 4,5 Based on the temperature-dependent emission intensities of 2 H 11/2 and 4 S 3/2 TCLs of Er 3+ ions, Zhang et al, discovered that the absolute sensitivity (i.e., S a ) of Gd 9.33 (SiO 4 ) 6 O 2 :Er 3+ /Yb 3+ phosphors was 0.00464 K -1 .…”

Nano-Crystallization of Ln-Fluoride Crystals in Glass-Ceramics via Inducing of Yb3+ for Efficient Near-Infrared Upconversion Luminescence of Tm3+

“…Thus, Yb 3+ -Tm 3+ co-doped materials were more efficient candidates for NIR-to-NIR UC luminescence and were significant light sources for biologically non-destructive detection. In the past decades, a large number of investigations about Yb 3+ -Tm 3+ co-doped UC materials have been widely reported for achieving high-efficiency NIR UC luminescence [14][15][16][17][18][19][20].…”