Abstract
Photoluminescent materials are widely used in information security applications, yet high-precision optical information encryption remains difficult to achieve. Here we report two monoclinic zero-dimensional organic–inorganic hybrid Mn(II) chloride crystals (C19H42N)2MnCl4 and (C21H46N)2MnCl4. Both show green emission with photoluminescence quantum yields of 85.7% and 89.3%. Upon heating, photoluminescence (PL) is quenched abruptly at 333 and 343 K (ΔT = 10 K) and recovers upon cooling, driven by reversible order–disorder solid–solid phase transitions with phase-transition enthalpies of 140.6 and 160.3 J g–1, respectively. Using two closely spaced PL quenching temperatures, we demonstrate a temperature-window encryption scheme for optical information encryption and anti-counterfeiting, where correct information is revealed only within 333 ≤ T < 343 K. Furthermore, combining latent-heat storage with a temperature-gated PL ON/OFF readout provides a straightforward route to visualized thermal energy storage. This work reveals phase-transition-induced PL quenching and its applications in optical information encryption and visualized thermal energy storage, providing a strategy for designing multifunctional thermo-responsive luminescent materials.
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The data supporting the findings of this study are available within the Article and its Supplementary Information. Crystallographic data for the structures reported in this article have been deposited at the Cambridge Crystallographic Data Centre (CCDC), under deposition numbers 2359547 and 2405046. These data can be obtained free of charge from the CCDC via www.ccdc.cam.ac.uk/data_request/cif. The Figshare DOI is: https://doi.org/10.6084/m9.figshare.31223542.All data are available from the corresponding author upon request. Source data are provided with this paper.
References
Xie, Y. et al. Lanthanide-doped heterostructured nanocomposites toward advanced optical anti-counterfeiting and information storage. Light Sci. Appl. 11, 150 (2022).
Li, B., Cao, L., Zhou, B., Chen, X. & Zhang, J. Advanced time-resolved information security protection from synergistic effect of FRET and reversible photoresponsive iHOF. Adv. Opt. Mater. 13, 2500273 (2025).
Wang, Z. et al. Near-sensor neuromorphic computing system based on a thermopile infrared detector and a memristor for encrypted visual information transmission. Nano Lett 25, 8049–8057 (2025).
Jang, J. et al. Kerker-conditioned dynamic cryptographic nanoprints. Adv. Opt. Mater. 7, 1801070 (2019).
Liu, M. et al. Supramolecular assembly-driven multilevel fluorescent encryption. Angew. Chem. Int. Ed. 64, e202508935 (2025).
Liu, G. et al. Fluorescent, multifunctional anti-counterfeiting, fast response electrophoretic display based on TiO2/CsPbBr3 composite particles. Light Sci. Appl. 13, 198 (2024).
Liu, B.-M. et al. Excitation-wavelength-dependent persistent luminescence from single-component nonstoichiometric CaGaxO4: Bi for dynamic anti-counterfeiting. Light Sci. Appl. 13, 286 (2024).
Jin, J., Wang, Y., Han, K. & Xia, Z. Rigid phase formation and Sb3+ doping of tin (IV) halide hybrids toward photoluminescence enhancement and tuning for anti-counterfeiting and information encryption. Angew. Chem. Int. Ed 63, e202408653 (2024).
Chang, D. et al. Pressure-induced dual-emission of Mn-based metal halides (C5H6N)2MnBr4. Adv. Opt. Mater. 12, 2302829 (2024).
Xue, S., Shi, C., Xu, L. & Chen, Z. Thermal and vapor induced triple-mode luminescent switch of manganese(II) halides hybrid. Adv. Opt. Mater. 12, 2302854 (2024).
Yan, J. et al. A convenient, environmental-friendly, panchromatic adjustable, re-writable photonic paper and its optical anti-counterfeiting application. Chem. Eng. Sci. 288, 119818 (2024).
Zhu, X. et al. Temperature-dependent color-tunable afterglow in zirconium-doped CsCdCl3 perovskite for advanced anti-counterfeiting and thermal distribution detection. Small 20, 2306299 (2024).
Xiao, Y. et al. Thermally activated photochromism: Realizing temperature-gated triphenylethylene photochromic materials. Adv. Funct. Mater. 34, 2312930 (2024).
Mondal, P. P., Neem, M., Chand, R., Pandit, A. & Neogi, S. Luminescent metal–organic frameworks as multimodal platforms for advanced anticounterfeiting and security applications. Chem. Mater. 36, 10451–10473 (2024).
Wang, L. et al. High-dimensional anticounterfeiting nanodiamonds authenticated with deep metric learning. Nat. Commun. 15, 10602 (2024).
Li, L., Jin, J., Han, K., Wang, Y. & Xia, Z. Rational design and synthesis of narrow-band emitting Eu(II)-based hybrid halides via alkyl thermal cleavage. Nat. Commun. 16, 7479 (2025).
Lian, L. et al. Solubility-driven rapid and large-scale synthesis of solvatochromic luminescent organic–inorganic manganese(II)-based halides for advanced anti-counterfeiting. Laser Photonics Rev 19, e00509 (2025).
Luo, Z. et al. Integrated afterglow and self-trapped exciton emissions in hybrid metal halides for anti-counterfeiting applications. Adv. Mater. 34, 2200607 (2022).
Liang, D. et al. Mn2+-based luminescent metal halides: Syntheses, properties, and applications. Adv. Opt. Mater. 11, 2202997 (2023).
Träger, L. M. et al. Mn2+-activated alkali lithooxidosilicate phosphors as sustainable alternative white-light emitters. Angew. Chem. Int. Ed. 64, e202504078 (2025).
Lin, S. et al. High-security-level multi-dimensional optical storage medium: nanostructured glass embedded with LiGa5O8:Mn2+ with photostimulated luminescence. Light Sci. Appl. 9, 22 (2020).
Liu, G. et al. Thermally induced reversible phase transition and photoluminescence switching behavior of (NH4)2MnBr4(H2O)2 crystals. J. Mater. Chem. C. 13, 910–917 (2025).
Wu, Y. et al. Strategic engineering of cationic systems for spatial & temporal anti-counterfeiting applications in zero-dimensional Mn(II) halides. J. Colloid Interface Sci. 678, 430–440 (2025).
Lun, M. et al. Unusual thermal quenching of photoluminescence from an organic–inorganic hybrid [MnBr4]2−-based halide mediated by crystalline–crystalline phase transition. Angew. Chem. Int. Ed. 63, e202313590 (2024).
He, Z., Wei, J., Luo, J., Zhang, Z. & Kuang, D. Reversible human-temperature-responsive luminescence switching in a Mn(II)-based metal halide. J. Mater. Chem. C. 11, 1251–1257 (2023).
Seo, J. et al. Colossal barocaloric effects with ultralow hysteresis in two-dimensional metal–halide perovskites. Nat. Commun. 13, 2536 (2022).
Wang, C. et al. Multiple H-bonding cross-linked supramolecular solid–solid phase change materials for thermal energy storage and management. Adv. Mater. 36, 2309723 (2024).
Dalley, E. J. et al. Chain-melting temperature depression in the organic layer of two-dimensional perovskites. ACS Energy Lett 9, 5756–5762 (2024).
Ricard, L., Cavagnat, R. & Rey-Lafon, M. Vibrational study of the dynamics of n-alkylammonium chains in the perovskite-type layer compounds (CnH2n+1NH3)2CdCl4(n = 8, 12, 16). J. Phys. Chem. 89, 4887–4894 (1985).
Li, J. et al. Colossal reversible barocaloric effects in layered hybrid perovskite (C10H21NH3)2MnCl4 under low pressure near room temperature. Adv. Funct. Mater. 31, 2105154 (2021).
Jin, Y.J. et al. Phase-change hybrids for thermo-responsive sensors and actuators. NPG Asia Mater 6, e137 (2014).
Zhang, S. et al. Dipole-orientation-dependent förster resonance energy transfer from aromatic head groups to MnBr42– blocks in organic–inorganic hybrids. J. Phys. Chem. Lett. 12, 8692–8698 (2021).
Liu, D. et al. Near-infrared emitting metal halide materials: Luminescence design and applications. InfoMat. 6, e12542 (2024).
Ma, Y. et al. Solvent-free mechanochemical syntheses of microscale lead-free hybrid manganese halides as efficient green light phosphors. J. Mater. Chem. C. 9, 9952–9961 (2021).
Yang, Q. et al. Two organic–inorganic manganese(II) halide hybrids showing compelling photo- and mechanoluminescence as well as rewritable anticounterfeiting printing. Inorg. Chem. 62, 5791–5798 (2023).
Liu, Y. et al. Reversible structural transformations and color-tunable emissions in organic manganese halides. Chem. Commun. 59, 10267–10270 (2023).
Cong, L. et al. Manganese halides with timely and delayed reversible thermal fluorescence quenching for dual-secure information encryption and anti-counterfeiting. Chem. Eng. J. 505, 159672 (2025).
Su, B., Molokeev, M. S., Chen, R. & Zhang, T. Near-unity PLQY and high anti-thermal quenching red luminescence from one-dimensional hybrid manganese chloride for efficient and stable white light-emitting diodes. J. Mater. Chem. C. 12, 9266–9273 (2024).
Zou, X. et al. In situ synthesis of highly emissive manganese halides with modified bisphosphonium cations toward information encryption. Inorg. Chem. 64, 4133–4140 (2025).
Chang, T. et al. Temperature-dependent reversible optical properties of Mn-based organic–inorganic hybrid (C8H20N)2MnCl4 metal halides. ACS Appl. Mater. Interfaces. 15, 5487–5494 (2023).
Kresse, G. & Joubert, D. From ultrasoft pseudopotentials to the projector augmented-wave method. Phys. Rev. B 59, 1758–1775 (1999).
Wei, Y. et al. High quantum yield and unusual photoluminescence behaviour in tetrahedral manganese(Ⅱ) based on hybrid compounds. Inorg. Chem. Front. 5, 2615–2619 (2018).
Li, L. et al. Highly flexible GO–polyurethane solid–solid phase change composite materials for efficient photothermal conversion and thermal energy storage. J. Mater. Chem. A 13, 3073–3083 (2025).
Yang, L., Jin, X., Zhang, Y. & Du, K. Recent development on heat transfer and various applications of phase-change materials. J. Cleaner Prod. 287, 124432 (2021).
Peticolas, W. L., Hibler, G. W., Lippert, J. L., Peterlin, A. & Olf, H. Raman scattering from longitudinal acoustical vibrations of single crystals of polyethylene. Appl. Phys. Lett. 18, 87–89 (1971).
Viras, F., Viras, K., Campbell, C., King, T. A. & Booth, C. Low-frequency Raman spectra of odd α,ω-disubstituted n -alkanes. J. Polym. Sci., Part B: Polym. Phys. 29, 1467–1471 (1991).
Sadok, I. B. H. et al. Crystal structure, optical and electrical properties of metal-halide compound [C7H16N2][ZnCl4]. J. Phys. Chem. Solids 129, 71–80 (2019).
Qiu, Y. et al. Variable-temperature Raman spectroscopy study of the phase transition mechanism in asphalt binders. Energy Fuels 37, 10296–10309 (2023).
Mączka, M., Smółka, S. & Ptak, M. Phonon properties and lattice dynamics of two- and tri-layered lead iodide perovskites comprising butylammonium and methylammonium cations—temperature-dependent raman studies. Materials 17, 2503 (2024).
Acknowledgements
This work was financially supported by Yunnan Fundamental Research Program (202301AS070002 to Z.L.W, 202501AT070006 to Q.W) and National Natural Science Foundation of China (22165033 to Z.L.W, 22365034 to Q.Z).
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A.B.L.: Methodology, Investigation, Writing - review & editing. Z.Q.C.: Investigation, Writing - review & editing. Z.L.W.: Conceptualization, Methodology, Writing - review & editing, Supervision, Funding acquisition. P.R.: Investigation, Methodology. Q.W.: Conceptualization, Supervision, Funding acquisition. Y.Y.Z.: Conceptualization, Methodology. Q.Z.: Writing - review & editing, Methodology. H.J.T.: Writing - review & editing, Methodology. All authors discussed and edited the paper.
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Li, A., Chen, Z., Wang, Z. et al. Reversible phase-transformation-induced thermal quenching in Mn(II) chlorides for high-precision information encryption and thermal energy storage. Nat Commun (2026). https://doi.org/10.1038/s41467-026-71277-3
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DOI: https://doi.org/10.1038/s41467-026-71277-3
