Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

A polydimethylsiloxane-coated metal structure for all-day radiative cooling


Radiative cooling is a passive cooling strategy with zero consumption of electricity that can be used to radiate heat from buildings to reduce air-conditioning requirements. Although this technology can work well during optimal atmospheric conditions at night, it is essential to achieve efficient cooling during the daytime when peak cooling demand actually occurs. Here we report an inexpensive planar polydimethylsiloxane (PDMS)/metal thermal emitter thin film structure, which was fabricated using a fast solution coating process that is scalable for large-area manufacturing. By performing tests under different environmental conditions, temperature reductions of 9.5 °C and 11.0 °C were demonstrated in the laboratory and an outside environment, respectively, with an average cooling power of ~120 W m2 for the thin film thermal emitter. In addition, a spectral-selective structure was designed and implemented to suppress the solar input and control the divergence of the thermal emission beam. This enhanced the directionality of the thermal emissions, so the emitter’s cooling performance was less dependent on the surrounding environment. Outside experiments were performed in Buffalo, New York, realizing continuous all-day cooling of ~2–9 °C on a typical clear sunny day at Northern United States latitudes. This practical strategy that cools without electricity input could have a significant impact on global energy consumption.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Fig. 1: PDMS/metal thin film thermal emitter.
Fig. 2: Indoor radiative cooling characterization using liquid nitrogen as the cold source.
Fig. 3: Outdoor radiative cooling test over different emission angles.
Fig. 4: Beaming effect and solar shelter for daytime cooling.
Fig. 5: All-day continuous radiative cooling.

Data availability

The data that support the findings of this study are available from the corresponding authors on request.


  1. Kelso, J. K. 2011 Buildings Energy Data Book (US Department of Energy, 2012).

  2. Chu, S. & Majumdar, A. Opportunities and challenges for a sustainable energy future. Nature 488, 294–303 (2012).

    Article  CAS  Google Scholar 

  3. Segar, C. Renewable augment gas—Saudi energy mix. J. Int. Energy Agency 7, 40–41 (2014).

    Google Scholar 

  4. Mahdavinejad, M. & Javanrudi, K. Assessment of ancient fridges: a sustainable method to storage ice in hot-arid climates. Asian Cult. Hist. 4, 133–139 (2012).

    Google Scholar 

  5. Catalanotti, S. et al. The radiative cooling of selective surfaces. Sol. Energy 17, 83–89 (1975).

    Article  Google Scholar 

  6. Fan, S. Thermal photonics and energy applications. Joule 1, 264–273 (2017).

    Article  CAS  Google Scholar 

  7. Hossain Md, M. & Gu, M. Radiative cooling: principles, progress, and potentials. Adv. Sci. 3, 1500360 (2016).

    Article  Google Scholar 

  8. Sun, X., Sun, Y., Zhou, Z., Alam Muhammad, A. & Bermel, P. Radiative sky cooling: fundamental physics, materials, structures, and applications. Nanophotonics 6, 997–1015 (2017).

    Article  Google Scholar 

  9. Buddhiraju, S., Santhanam, P. & Fan, S. Thermodynamic limits of energy harvesting from outgoing thermal radiation. Proc. Natl Acad. Sci. USA 115, E3609–E3615 (2018).

    Article  CAS  Google Scholar 

  10. Raman, A. P., Anoma, M. A., Zhu, L., Rephaeli, E. & Fan, S. Passive radiative cooling below ambient air temperature under direct sunlight. Nature 515, 540–544 (2014).

    Article  CAS  Google Scholar 

  11. Zhai, Y. et al. Scalable-manufactured randomized glass-polymer hybrid metamaterial for daytime radiative cooling. Science 355, 1062–1066 (2017).

    Article  CAS  Google Scholar 

  12. Mandal, J. et al. Hierachically porous polymer coatings for highly efficient passive daytime radiative cooling. Science 362, 315–319 (2018).

    Article  CAS  Google Scholar 

  13. Zhu, L., Raman, A., Wang, K. X., Anoma, M. A. & Fan, S. Radiative cooling of solar cells. Optica 1, 32–38 (2014).

    Article  CAS  Google Scholar 

  14. Li, W., Shi, Y., Chen, K., Zhu, L. & Fan, S. A comprehensive photonic approach for solar cell cooling. ACS Photonics 4, 774–782 (2017).

    Article  CAS  Google Scholar 

  15. Zhu, L., Raman, A. P. & Fan, S. Radiative cooling of solar absorbers using a visibly transparent photonic crystal thermal blackbody. Proc. Natl Acad. Sci. USA 112, 12282–12287 (2015).

    Article  CAS  Google Scholar 

  16. Shi, Y., Li, W., Raman, A. & Fan, S. Optimization of multilayer optical films with a memetic algorithm and mixed integer programming. ACS Photonics 5, 684–691 (2018).

    Article  CAS  Google Scholar 

  17. Rephaeli, E., Raman, A. & Fan, S. Ultrabroadband photonic structures to achieve high-performance daytime radiative cooling. Nano Lett. 13, 1457–1461 (2013).

    Article  CAS  Google Scholar 

  18. Yuan, H. et al. Effective, angle-independent radiative cooler based on one-dimensional photonic crystal. Opt. Express 26, 27885–27893 (2018).

    Article  CAS  Google Scholar 

  19. Chen, Z., Zhu, L., Raman, A. & Fan, S. Radiative cooling to deep sub-freezing temperatures through a 24-h day–night cycle. Nat. Commun. 7, 13729 (2016).

    Article  CAS  Google Scholar 

  20. Bhatia, B. et al. Passive directional sub-ambient daytime radiative cooling. Nat. Commun. 9, 5001 (2018).

    Article  Google Scholar 

  21. Goldstein, E. A., Raman, A. P. & Fan, S. Sub-ambient non-evaporative fluid cooling with the sky. Nat. Energy 2, 17143 (2017).

    Article  Google Scholar 

  22. Angus, R. G. & Geoff, B. S. A subambient open roof surface under the mid-summer sun. Adv. Sci. 2, 1500119 (2015).

    Article  Google Scholar 

  23. Lu, X., Xu, P., Wang, H., Yang, T. & Hou, J. Cooling potential and applications prospects of passive radiative cooling in buildings: the current state-of-the-art. Renew. Sustain. Energy Rev. 65, 1079–1097 (2016).

    Article  Google Scholar 

  24. Lee, G. J., Kim, Y. J., Kim, H. M., Yoo, Y. J. & Song, Y. M. Colored, daytime radiative coolers with thin-film resonators for aesthetic purposes. Adv. Opt. Mater. 6, 1800707 (2018).

    Article  Google Scholar 

  25. Hoyt, T., Arens, E. & Zhang, H. Extending air temperature setpoints: simulated energy savings and design considerations for new and retrofit buildings. Build. Environ. 88, 89–96 (2015).

    Article  Google Scholar 

  26. Li, W., Shi, Y., Chen, Z. & Fan, S. Photonic thermal management of coloured objects. Nat. Commun. 9, 4240 (2018).

    Article  Google Scholar 

  27. Li, T. et al. A radiative cooling structural material. Science 364, 760–763 (2019).

    Article  CAS  Google Scholar 

  28. Hsu, P.-C. et al. Radiative human body cooling by nanoporous polyethylene textile. Science 353, 1019–1023 (2016).

    Article  CAS  Google Scholar 

  29. Hsu, P.-C. et al. A dual-mode textile for human body radiative heating and cooling. Sci. Adv. 3, e1700895 (2017).

    Article  Google Scholar 

  30. Kou, J.-l, Jurado, Z., Chen, Z., Fan, S. & Minnich, A. J. Daytime radiative cooling using near-black infrared emitters. ACS Photonics 4, 626–630 (2017).

    Article  CAS  Google Scholar 

  31. Atiganyanun, S. et al. Effective radiative cooling by paint-format microsphere-based photonic random media. ACS Photonics 5, 1181–1187 (2018).

    Article  CAS  Google Scholar 

  32. Peng, Y. et al. Nanoporous polyethylene microfibres for large-scale radiative cooling fabric. Nat. Sustain. 1, 105–112 (2018).

    Article  Google Scholar 

  33. Nilsson, T. M. J. & Niklasson, G. A. Radiative cooling during the day: simulations and experiments on pigmented polyethylene cover foils. Sol. Energy Mater. Sol. Cells 37, 93–118 (1995).

    Article  CAS  Google Scholar 

  34. Huang, Z. & Ruan, X. Nanoparticle embedded double-layer coating for daytime radiative cooling. Int. J. Heat Mass Transf. 104, 890–896 (2017).

    Article  CAS  Google Scholar 

  35. Dobson, K. D., Hodes, G. & Mastai, Y. Thin semiconductor films for radiative cooling applications. Sol. Energy Mater. Sol. Cells 80, 283–296 (2003).

    Article  CAS  Google Scholar 

  36. Gentle, A. R., Nuhoglu, A., Arnold, M. D. & Smith, G. B. 3D printable optical structures for sub-ambient sky cooling. Proc. SPIE 10369, 103690B (2017).

  37. Gentle, A. R. & Smith, G. B. Angular selectivity: impact on optimised coatings for night sky radiative cooling. Proc. SPIE 7404, 74040J (2009);

  38. Smith, G. B. Amplified radiative cooling via optimised combinations of aperture geometry and spectral emittance profiles of surfaces and the atmosphere. Sol. Energy Mater. Sol. Cells 93, 1696–1701 (2009).

    Article  CAS  Google Scholar 

  39. Srinivasan, A., Czapla, B., Mayo, J. & Narayanaswamy, A. Infrared dielectric function of polydimethylsiloxane and selective emission behavior. Appl. Phys. Lett. 109, 061905 (2016).

    Article  Google Scholar 

  40. Greffet, J.-J. et al. Coherent emission of light by thermal sources. Nature 416, 61–64 (2002).

    Article  CAS  Google Scholar 

  41. Granqvist, C. G. & Hjortsberg, A. Radiative cooling to low temperatures: General considerations and application to selectively emitting SiO films. J. Appl. Phys. 52, 4205–4220 (1981).

    Article  CAS  Google Scholar 

Download references


This work was partially supported by the National Science Foundation (grant nos. IIP-1745846, ECCS-1507312, CBET-1445934 and ECCS-1425648).

Author information

Authors and Affiliations



Q.G., B.O. and Z.Y conceived the idea and supervised the project. L.Z., H.S., J.L., E.S. and T.N. executed the experiments. All authors contributed to the analysis of the experimental results and modelling. L.Z., H.S., Z.Y., B.O. and Q.G. wrote the manuscript. All authors reviewed the manuscript.

Corresponding authors

Correspondence to Zongfu Yu, Boon Ooi or Qiaoqiang Gan.

Ethics declarations

Competing interests

Q.G. and Z.Y. have founded a company, Sunny Clean Water LLC, seeking to commercialize the results reported in this paper.

Additional information

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Figs. 1–9, Notes 1–6 and Refs. 1–3

Supplementary Video 1

Short clip showing application of PDMS coating to metal.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Zhou, L., Song, H., Liang, J. et al. A polydimethylsiloxane-coated metal structure for all-day radiative cooling. Nat Sustain 2, 718–724 (2019).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:

This article is cited by


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing