Issue

Vol. 18 (2026)

Dual-Functional Photonic Metacoating Integrating Fluorescence Thermometry and High-Performance Space Radiative Cooling

https://doi.org/10.1007/s40820-026-02195-8
Hao Gong
State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
Zhongyang Wang
State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
Yan Zheng
State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
Liping Tong
School of Materials, Shanghai Dianji University, Shanghai 201306, People’s Republic of China
Hongchao Li
State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
Zhiyuan Zhao
State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
Junjia Liu
State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
Gang Liu
Shanghai Institute of Spacecraft Equipment, Shanghai 200240, People’s Republic of China
Xiao Zhou
State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China
Tongxiang Fan
State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China

Corresponding Author: Tongxiang Fan

txfan@sjtu.edu.cn

Nano-Micro Letters, Vol. 18 (2026), Article Number: 349

Abstract

Fluorescence thermometry offers a non-contact strategy for early detection of thermal instabilities on complex spacecraft surfaces, enabling reliable in-orbit temperature mapping. However, simultaneously achieving high-sensitivity fluorescence thermometry and efficient space radiative cooling remains challenging, as enhanced visible absorption improves thermometric response but increases solar heating. Here, we address this trade-off through a material-structure co-design strategy by developing an Eu-doped ZrO2 submicrosphere metacoating that integrates space radiative cooling with fluorescence-based temperature sensing. Guided by photonic-structure optimization using a constrained-gradient optimizer combined with grid-search mapping, the optimized metacoating, featuring a submicrosphere diameter of 0.756 µm and a volume fraction of 35%, achieves an ultralow solar absorptance (αs = 0.076) and a high thermal emittance (ε = 0.931). In parallel, bandgap-driven compositional optimization identifies an optimal Eu content of 8.48%, enabling outstanding thermometric performance. The metacoating delivers a net cooling power of 323.69 W m−2 and a 77 °C temperature reduction relative to an Al sheet, outperforming representative oxide-based inorganic coatings. It allows temperature sensing over 173–433 K with a maximum relative sensitivity of 0.797% K−1, surpassing fluorescent oxides with comparable absorption edges. Moreover, the metacoating maintains the lowest αs and reliable irradiation resistance under proton, electron, atomic oxygen and ultraviolet exposures, outperforming reported counterparts. Together with its scalable fabrication, this work establishes a dual-functional metacoating platform for intelligent spacecraft thermal management that combines efficient radiative cooling with high-sensitivity fluorescence thermometry.


Highlights:
1 Dual-functional Eu-doped ZrO2 submicrosphere metacoating for space radiative cooling and fluorescence thermometry.
2 Photonic structure and materials co-design yield an ultralow solar absorptance (αs = 0.076) and high emittance (ε = 0.931) in a ~ 100 μm thick metacoating.
3 The metacoating achieves a net cooling power of 323.69 W m−2 and enables 173–433 K non-contact thermometry (Sr,max = 0.797% K−1) with reliable irradiation resistance under space environments.

Keywords

Photonic metacoating Eu-doped ZrO2 submicrosphere Space radiative cooling Fluorescence thermometry
Gong, Hao, Zhongyang Wang, Yan Zheng, Liping Tong, Hongchao Li, Zhiyuan Zhao, Junjia Liu, Gang Liu, Xiao Zhou, and Tongxiang Fan. 2026. “Dual-Functional Photonic Metacoating Integrating Fluorescence Thermometry and High-Performance Space Radiative Cooling”. Nano-Micro Letters 18 (April):349. https://doi.org/10.1007/s40820-026-02195-8.
Download Citation
Endnote/Zotero/Mendeley (RIS)
BibTeX
References
  1. A. Aili, J. Choi, Y.S. Ong, Y. Wen, The development of carbon-neutral data centres in space. Nat. Electron. 8(11), 1016–1026 (2025). https://doi.org/10.1038/s41928-025-01476-1
  2. Y. Fan, H. Chen, X. Liu, Y. Zhao, Y. Huang et al., Radiative cooling in outer space: fundamentals, advances in materials and applications, and perspectives. Adv. Mater. 37(43), e06795 (2025). https://doi.org/10.1002/adma.202506795
  3. J. Xu, W. Xie, H. Han, C. Xiao, J. Li et al., Radiative cooling materials for extreme environmental applications. Nano-Micro Lett. 17(1), 324 (2025). https://doi.org/10.1007/s40820-025-01835-9
  4. Y. Dong, B. Tian, C. Wang, G. Zhang, F. Hua et al., Dynamic radiative cooling: mechanisms, strategies, and applications for smart thermal management. Nano-Micro Lett. 18(1), 146 (2026). https://doi.org/10.1007/s40820-025-01981-0
  5. A.-Q. Xie, H. Qiu, W. Jiang, Y. Wang, S. Niu et al., Recent advances in spectrally selective daytime radiative cooling materials. Nano-Micro Lett. 17(1), 264 (2025). https://doi.org/10.1007/s40820-025-01771-8
  6. B. Gao, X. Jia, X. Wang, H. Kang, S. Lu et al., Synthesis of high solar reflectance hierarchical porous thermal control coating via alkali-induced assembly for spacecraft. Mater. Today Phys. 58, 101850 (2025). https://doi.org/10.1016/j.mtphys.2025.101850
  7. J. Lv, J. Xie, N. Vitaly, Development of Zn2SiO4 and hexagonal BN inorganic thermal-control coatings with novel thermophysical property. Int. J. Heat Mass Transf. 218, 124791 (2024). https://doi.org/10.1016/j.ijheatmasstransfer.2023.124791
  8. Y. Xiao, A. Feng, J. Chen, Q. Cao, L. Mi et al., MgGa2O4-based thermal control coating: an ultra-low solar absorption coating with high irradiation stability. Ceram. Int. 50(18), 33480–33487 (2024). https://doi.org/10.1016/j.ceramint.2024.06.163
  9. H. Gong, Z. Wang, X. Song, H. Li, K. Sun et al., Zirconia submicrosphere/potassium silicate metacoating with high irradiation stability for radiative cooling. Adv. Compos. Hybrid Mater. 8(1), 106 (2025). https://doi.org/10.1007/s42114-024-01130-y
  10. C.D.S. Brites, R. Marin, M. Suta, A.N. Carneiro Neto, E. Ximendes et al., Spotlight on luminescence thermometry: basics, challenges, and cutting-edge applications. Adv. Mater. 35(36), e2302749 (2023). https://doi.org/10.1002/adma.202302749
  11. H. Suo, X. Zhao, Z. Zhang, Y. Wang, J. Sun et al., Rational design of ratiometric luminescence thermometry based on thermally coupled levels for bioapplications. Laser Photonics Rev. 15(1), 2000319 (2021). https://doi.org/10.1002/lpor.202000319
  12. J. Zhou, B. del Rosal, D. Jaque, S. Uchiyama, D. Jin, Advances and challenges for fluorescence nanothermometry. Nat. Methods 17(10), 967–980 (2020). https://doi.org/10.1038/s41592-020-0957-y
  13. F. Jahanbazi, Y. Mao, Recent advances on metal oxide-based luminescence thermometry. J. Mater. Chem. C 9(46), 16410–16439 (2021). https://doi.org/10.1039/d1tc03455c
  14. C. Alexander, Z. Guo, P.B. Glover, S. Faulkner, Z. Pikramenou, Luminescent lanthanides in biorelated applications: from molecules to nanops and diagnostic probes to therapeutics. Chem. Rev. 125(4), 2269–2370 (2025). https://doi.org/10.1021/acs.chemrev.4c00615
  15. K. Zheng, K.Y. Loh, Y. Wang, Q. Chen, J. Fan et al., Recent advances in upconversion nanocrystals: expanding the kaleidoscopic toolbox for emerging applications. Nano Today 29, 100797 (2019). https://doi.org/10.1016/j.nantod.2019.100797
  16. A. Gu, G.-H. Pan, H. Wu, L. Zhang, L. Zhang et al., Microstructure and photoluminescence of ZrTiO4: Eu3+ phosphors: host-sensitized energy transfer and optical thermometry. Chemosensors 10(12), 527 (2022). https://doi.org/10.3390/chemosensors10120527
  17. A. Bindhu, J.I. Naseemabeevi, S. Ganesanpotti, Vibrationally induced photophysical response of Sr2NaMg2V3O12: Eu3+ for dual-mode temperature sensing and safety signs. Adv. Photonics Res. 3(6), 2100159 (2022). https://doi.org/10.1002/adpr.202100159
  18. Y. Chen, J. Chen, Y. Luo, Q. Wang, H. Guo, Ba2LuNbO6: Er3+, Yb3+ up-conversion phosphors for dual-mode thermometry based on fluorescence intensity ratio. J. Am. Ceram. Soc. 107(12), 8246–8255 (2024). https://doi.org/10.1111/jace.20058
  19. X. Fan, L. Xu, W. Liu, F. Yin, J. Xu et al., Energy transfer in dual-emission LiY6(BO3)3O5: Bi3+, Eu3+ phosphors for temperature sensing applications. Ceram. Int. 50(18), 32583–32590 (2024). https://doi.org/10.1016/j.ceramint.2024.06.066
  20. X. Shi, Y. Chen, G. Li, K. Qiang, Q. Mao et al., Designing a dual-wavelength excitation Eu3+/Mn4+ Co-doped phosphors for high-sensitivity luminescence thermometry. Ceram. Int. 49(12), 20839–20848 (2023). https://doi.org/10.1016/j.ceramint.2023.03.217
  21. A.A. Nashivochnikov, A.I. Kostyukov, M.I. Rakhmanova, S.V. Cherepanova, V.N. Snytnikov, Photoluminescence and structure evolution of laser synthesized ZrO2: Eu3+ nanopowders depending on the dopant concentration. Ceram. Int. 49(3), 5049–5057 (2023). https://doi.org/10.1016/j.ceramint.2022.10.018
  22. M.D. Chambers, D.R. Clarke, Doped oxides for high-temperature luminescence and lifetime thermometry. Annu. Rev. Mater. Res. 39, 325–359 (2009). https://doi.org/10.1146/annurev-matsci-112408-125237
  23. A.A. Nashivochnikov, A.I. Kostyukov, A.V. Zhuzhgov, M.I. Rakhmanova, S.V. Cherepanova et al., Shaping the photoluminescence spectrum of ZrO2: Eu3+ phosphor in dependence on the Eu concentration. Opt. Mater. 121, 111620 (2021). https://doi.org/10.1016/j.optmat.2021.111620
  24. H. Li, X. Song, H. Gong, L. Tong, X. Zhou et al., Prediction of optical properties in particulate media using double optimization of dependent scattering and p distribution. Nano Lett. 24(1), 287–294 (2024). https://doi.org/10.1021/acs.nanolett.3c03914
  25. X. Song, H. Li, H. Gong, X. Liu, M. Zhang et al., Machine learning prediction framework for tailoring the optical response of particulate media. ACS Photonics 12(5), 2775–2786 (2025). https://doi.org/10.1021/acsphotonics.5c00364
  26. X.-Q. Yu, F. Li, J. Wang, N. Zhang, G.-X. Li et al., Scalable-designed photonic metamaterial for color-regulating passive daytime radiative cooling. Nano-Micro Lett. 18(1), 153 (2026). https://doi.org/10.1007/s40820-025-01975-y
  27. L. Lei, T. Wu, S. Shi, Y. Si, C. Zhi et al., Engineered radiative cooling systems for thermal-regulating and energy-saving applications. Nano-Micro Lett. 18(1), 21 (2025). https://doi.org/10.1007/s40820-025-01859-1
  28. H. Gong, X. Song, H. Li, L. Tong, Z. Wang et al., Controllable synthesis of monodispersed zirconia submicrospheres based on oligomer aggregation mechanism for enhanced scattering manipulation. Small Methods 9(7), 2401990 (2025). https://doi.org/10.1002/smtd.202401990
  29. H. Gong, L. Tong, Z. Wang, X. Song, H. Li et al., Material and structure tailored La-doped ZrO2 submicrosphere metacoatings for high-performance space radiative cooling. Adv. Funct. Mater. (2026). https://doi.org/10.1002/adfm.202528343
  30. G. Kresse, D. Joubert, From ultrasoft pseudopotentials to the projector augmented-wave method. Phys. Rev. B 59(3), 1758–1775 (1999). https://doi.org/10.1103/physrevb.59.1758
  31. J.P. Perdew, K. Burke, M. Ernzerhof, Generalized gradient approximation made simple. Phys. Rev. Lett. 77(18), 3865–3868 (1996). https://doi.org/10.1103/physrevlett.77.3865
  32. G. Kresse, J. Furthmüller, Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set. Comput. Mater. Sci. 6(1), 15–50 (1996). https://doi.org/10.1016/0927-0256(96)00008-0
  33. L. Tong, N. Xu, H. Li, L. Yang, Z. Wang et al., Investigation of thermal control in phase-changing ABO3 perovskites via first-principles predictions: general mechanism of emittance. Phys. Chem. Chem. Phys. 25(10), 7302–7311 (2023). https://doi.org/10.1039/D3CP01493B
  34. H. Ma, L. Wang, S. Dou, H. Zhao, M. Huang et al., Flexible daytime radiative cooling enhanced by enabling three-phase composites with scattering interfaces between silica microspheres and hierarchical porous coatings. ACS Appl. Mater. Interfaces 13(16), 19282–19290 (2021). https://doi.org/10.1021/acsami.1c02145
  35. Z. Huang, X. Ruan, Nanop embedded double-layer coating for daytime radiative cooling. Int. J. Heat Mass Transf. 104, 890–896 (2017). https://doi.org/10.1016/j.ijheatmasstransfer.2016.08.009
  36. J. Peoples, X. Li, Y. Lv, J. Qiu, Z. Huang et al., A strategy of hierarchical p sizes in nanop composite for enhancing solar reflection. Int. J. Heat Mass Transf. 131, 487–494 (2019). https://doi.org/10.1016/j.ijheatmasstransfer.2018.11.059
  37. L. Wang, S.L. Jacques, L. Zheng, MCML: Monte Carlo modeling of light transport in multi-layered tissues. Comput. Methods Programs Biomed. 47(2), 131–146 (1995). https://doi.org/10.1016/0169-2607(95)01640-f
  38. W.E. Vargas, A. Amador, G.A. Niklasson, Diffuse reflectance of TiO2 pigmented paints: spectral dependence of the average pathlength parameter and the forward scattering ratio. Opt. Commun. 261(1), 71–78 (2006). https://doi.org/10.1016/j.optcom.2005.11.059
  39. X. Xue, M. Qiu, Y. Li, Q.M. Zhang, S. Li et al., Creating an eco-friendly building coating with smart subambient radiative cooling. Adv. Mater. 32(42), e1906751 (2020). https://doi.org/10.1002/adma.201906751
  40. A. Yurdakul, H. Gocmez, One-step hydrothermal synthesis of yttria-stabilized tetragonal zirconia polycrystalline nanopowders for blue-colored zirconia-cobalt aluminate spinel composite ceramics. Ceram. Int. 45(5), 5398–5406 (2019). https://doi.org/10.1016/j.ceramint.2018.11.240
  41. A. Auxéméry, G. Philippot, M.R. Suchomel, D. Testemale, C. Aymonier, Stabilization of tetragonal zirconia nanocrystallites using an original supercritical-based synthesis route. Chem. Mater. 32(19), 8169–8181 (2020). https://doi.org/10.1021/acs.chemmater.0c01550
  42. X. Zheng, P. Yu, Y. Liu, Y. Ma, Y. Cao et al., Efficient hydrogenation of methyl palmitate to hexadecanol over Cu/m-ZrO2 catalysts: synergistic effect of Cu species and oxygen vacancies. ACS Catal. 13(3), 2047–2060 (2023). https://doi.org/10.1021/acscatal.2c06151
  43. S. Fu, C. Hu, J. Li, H. Cui, Y. Liu et al., Tuning the crystalline and electronic structure of ZrO2 via oxygen vacancies and nano-structuring for polysulfides conversion in lithium-sulfur batteries. J. Energy Chem. 88, 82–93 (2024). https://doi.org/10.1016/j.jechem.2023.09.003
  44. J.Y. Park, C.G. Lee, H.W. Seo, D.-W. Jeong, M.Y. Kim et al., Structural and optical properties of ZnSe: Eu/ZnS quantum dots depending on interfacial residual europium. Appl. Surf. Sci. 429, 225–230 (2018). https://doi.org/10.1016/j.apsusc.2017.09.018
  45. E. Wang, L. Li, J.-Y. Zou, S.-Y. You, R.-J. Hu et al., Regulating the energy level of a ratiometric luminescent europium(III) metal–organic framework sensor with smartphone assistance for real-time and visual detection of carcinoid biomarker. Inorg. Chem. 64(8), 3930–3940 (2025). https://doi.org/10.1021/acs.inorgchem.4c05180
  46. E.R. Khattab, S.S. Abd El Rehim, W.M.I. Hassan, T.S. El-Shazly, Band structure engineering and optical properties of pristine and doped monoclinic zirconia (m-ZrO2): density functional theory theoretical prospective. ACS Omega 6(44), 30061–30068 (2021). https://doi.org/10.1021/acsomega.1c04756
  47. P. Makuła, M. Pacia, W. Macyk, How to correctly determine the band gap energy of modified semiconductor photocatalysts based on UV–vis spectra. J. Phys. Chem. Lett. 9(23), 6814–6817 (2018). https://doi.org/10.1021/acs.jpclett.8b02892
  48. G.-H. Pan, L. Zhang, H. Wu, X. Qu, H. Wu et al., On the luminescence of Ti4+ and Eu3+ in monoclinic ZrO2: high performance optical thermometry derived from energy transfer. J. Mater. Chem. C 8(13), 4518–4533 (2020). https://doi.org/10.1039/C9TC06992E
  49. J. Zhou, R. Lei, H. Wang, Y. Hua, D. Li et al., A new generation of dual-mode optical thermometry based on ZrO2: Eu3+ nanocrystals. Nanophotonics 8(12), 2347–2358 (2018). https://doi.org/10.1515/nanoph-2019-0359
  50. J.M. Kim, S.M. Chang, S. Kim, K.-S. Kim, J. Kim et al., Design of SiO2/ZrO2 core–shell ps using the sol–gel process. Ceram. Int. 35(3), 1243–1247 (2009). https://doi.org/10.1016/j.ceramint.2008.06.003
  51. S. Kongwudthiti, P. Praserthdam, W. Tanakulrungsank, M. Inoue, The influence of Si–O–Zr bonds on the crystal-growth inhibition of zirconia prepared by the glycothermal method. J. Mater. Process. Technol. 136(1–3), 186–189 (2003). https://doi.org/10.1016/S0924-0136(03)00157-2
  52. J. Kaszewski, B.S. Witkowski, Wachnicki, T. Płociński, L.-I. Bulyk et al., Role of Zr3+ in excitation of Eu3+ ions in stabilized ZrO2: Eu nanops. J. Lumin. 273, 120654 (2024). https://doi.org/10.1016/j.jlumin.2024.120654
  53. H.S. Lokesha, M.L. Chithambo, A combined study of the thermoluminescence and electron paramagnetic resonance of point defects in ZrO2: Er3+. Radiat. Phys. Chem. 172, 108767 (2020). https://doi.org/10.1016/j.radphyschem.2020.108767
  54. J. Zhang, Y. Gao, X. Jia, J. Wang, Z. Chen et al., Oxygen vacancy-rich mesoporous ZrO2 with remarkably enhanced visible-light photocatalytic performance. Sol. Energy Mater. Sol. Cells 182, 113–120 (2018). https://doi.org/10.1016/j.solmat.2018.03.023
  55. J.-M. Costantini, F. Beuneu, W.J. Weber, Radiation damage in cubic-stabilized zirconia. J. Nucl. Mater. 440(1–3), 508–514 (2013). https://doi.org/10.1016/j.jnucmat.2013.02.041
Read More
Author biographies are not available.
Download this PDF file
PDF SUPPLEMENTARY FILE

Most read articles by the same author(s)