Light-responsive materials with high adsorption capacity and sunlight-triggered regenerability are highly desired for their low-cost and environmentally friendly industrial separation processes. Here we report a poly(spiropyran acrylate) (PSP) functionalized metal–organic framework (MOF) as a sunlight-regenerable ion adsorbent for sustainable water desalination. Under dark conditions, the zwitterionic isomer quickly adsorbs multiple cations and anions from water within 30 minutes, with high ion adsorption loadings of up to 2.88 mmol g−1 of NaCl. With sunlight illumination, the neutral isomer rapidly releases these adsorbed salts within 4 minutes. Single-column desalination experiments demonstrated that PSP–MOF works efficiently for water desalination. A freshwater yield of 139.5 l kg−1 d−1 and a low energy consumption of 0.11 Wh l−1 would be reached for desalinating 2,233 ppm synthetic brackish water. Importantly, this adsorbent shows excellent stability and cycling performance. This work opens up a new direction for designing stimuli-responsive materials for energy-efficient and sustainable desalination and water purification.
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Stokes, J. & Horvath, A. Life cycle energy assessment of alternative water supply systems. Int J. Life Cycle Assess. 11, 335–343 (2006).
Elimelech, M. & Phillip, W. A. The future of seawater desalination: energy, technology, and the environment. Science 333, 712–717 (2011).
Henderson‐Sellers, B. A new formula for latent heat of vaporization of water as a function of temperature. Q. J. R. Meteorol. Soc. 110, 1186–1190 (1984).
Al-Karaghouli, A. & Kazmerski, L. L. Energy consumption and water production cost of conventional and renewable-energy-powered desalination processes. Renew. Sustain. Energy Rev. 24, 343–356 (2013).
Burn, S. et al. Desalination techniques—a review of the opportunities for desalination in agriculture. Desalination 364, 2–16 (2015).
Ang, W. S., Yip, N. Y., Tiraferri, A. & Elimelech, M. Chemical cleaning of RO membranes fouled by wastewater effluent: achieving higher efficiency with dual-step cleaning. J. Memb. Sci. 382, 100–106 (2011).
Amy, G. et al. Membrane-based seawater desalination: present and future prospects. Desalination 401, 16–21 (2017).
Wang, Z. et al. Nanoarchitectured metal–organic framework/polypyrrole hybrids for brackish water desalination using capacitive deionization. Mater. Horiz. 6, 1433–1437 (2019).
Porada, S., Zhao, R., van der Wal, A., Presser, V. & Biesheuvel, P. M. Review on the science and technology of water desalination by capacitive deionization. Prog. Mater. Sci. 58, 1388–1442 (2013).
Chandrasekara, N. G. N. & Pashley, R. Study of a new process for the efficient regeneration of ion exchange resins. Desalination 357, 131–139 (2015).
Bolto, B. et al. An ion exchange process with thermal regeneration IX. A new type of rapidly reacting ion-exchange resin. Desalination 13, 269–285 (1973).
Ou, R. et al. Thermoresponsive amphoteric metal–organic frameworks for efficient and reversible adsorption of multiple salts from water. Adv. Mater. 30, 1802767 (2018).
Blankenship, R. E. et al. Comparing photosynthetic and photovoltaic efficiencies and recognizing the potential for improvement. Science 332, 805–809 (2011).
Ni, G. et al. Steam generation under one sun enabled by a floating structure with thermal concentration. Nat. Energy 1, 16126 (2016).
Tao, P. et al. Solar-driven interfacial evaporation. Nat. Energy 3, 1031–1041 (2018).
Chiavazzo, E., Morciano, M., Viglino, F., Fasano, M. & Asinari, P. Passive solar high-yield seawater desalination by modular and low-cost distillation. Nat. Sustain. 1, 763–772 (2018).
Scholes, G. D., Fleming, G. R., Olaya-Castro, A. & Van Grondelle, R. Lessons from nature about solar light harvesting. Nat. Chem. 3, 763–774 (2011).
Barber, J. Photosynthetic energy conversion: natural and artificial. Chem. Soc. Rev. 38, 185–196 (2009).
Li, X.-P. et al. A pigment-binding protein essential for regulation of photosynthetic light harvesting. Nature 403, 391–395 (2000).
Ferreira, K. N., Iverson, T. M., Maghlaoui, K., Barber, J. & Iwata, S. Architecture of the photosynthetic oxygen-evolving center. Science 303, 1831–1838 (2004).
Nagel, G. et al. Channelrhodopsin-2, a directly light-gated cation-selective membrane channel. Proc. Natl Acad. Sci. USA 100, 13940–13945 (2003).
Govorunova, E. G., Sineshchekov, O. A., Janz, R., Liu, X. & Spudich, J. L. Natural light-gated anion channels: a family of microbial rhodopsins for advanced optogenetics. Science 349, 647–650 (2015).
Roy, D., Cambre, J. N. & Sumerlin, B. S. Future perspectives and recent advances in stimuli-responsive materials. Prog. Polym. Sci. 35, 278–301 (2010).
Stuart, M. A. C. et al. Emerging applications of stimuli-responsive polymer materials. Nat. Mater. 9, 101–113 (2010).
Klajn, R. Spiropyran-based dynamic materials. Chem. Soc. Rev. 43, 148–184 (2014).
Radu, A. et al. Spiropyran-based reversible, light-modulated sensing with reduced photofatigue. J. Photochem. Photobiol. A 206, 109–115 (2009).
Furukawa, H., Cordova, K. E., O’Keeffe, M. & Yaghi, O. M. The chemistry and applications of metal–organic frameworks. Science 341, 1230444 (2013).
Bachman, J. E., Smith, Z. P., Li, T., Xu, T. & Long, J. R. Enhanced ethylene separation and plasticization resistance in polymer membranes incorporating metal–organic framework nanocrystals. Nat. Mater. 15, 845–849 (2016).
Loiseau, T. et al. A rationale for the large breathing of the porous aluminum terephthalate (MIL‐53) upon hydration. Chem. Eur. J. 10, 1373–1382 (2004).
Wang, C., Liu, X., Demir, N. K., Chen, J. P. & Li, K. Applications of water stable metal–organic frameworks. Chem. Soc. Rev. 45, 5107–5134 (2016).
Llewellyn, P. L. et al. Prediction of the conditions for breathing of metal organic framework materials using a combination of X-ray powder diffraction, microcalorimetry, and molecular simulation. J. Am. Chem. Soc. 130, 12808–12814 (2008).
Boutin, A. et al. Breathing transitions in MIL‐53 (Al) metal–organic framework upon xenon adsorption. Angew. Chem. Int. Ed. 48, 8314–8317 (2009).
Song, X., Zhou, J., Li, Y. & Tang, Y. Correlations between solvatochromism, Lewis acid–base equilibrium and photochromism of an indoline spiropyran. J. Photochem. Photobiol. A 92, 99–103 (1995).
Rosario, R., Gust, D., Hayes, M., Springer, J. & Garcia, A. A. Solvatochromic study of the microenvironment of surface-bound spiropyrans. Langmuir 19, 8801–8806 (2003).
Fissi, A., Pieroni, O., Angelini, N. & Lenci, F. Photoresponsive polypeptides: photochromic and conformational behavior of spiropyran-containing poly (L-glutamate) s under acid conditions. Macromolecules 32, 7116–7121 (1999).
Kho, Y. M. & Shin, E. J. Spiropyran-isoquinoline dyad as a dual chemosensor for Co(II) and In(III) detection. Molecules 22, 1569 (2017).
Kunin, R. Further studies on the weak electrolyte ion exchange resin desalination process (desal process). Desalination 4, 38–44 (1968).
Kunin, R. & McGarvey, F. X. Monobed deionization with ion exchange resins. Ind. Eng. Chem. 43, 734–740 (1951).
Bolto, B., Eppinger, K., Jackson, M. & Siudak, R. An ion-exchange process with thermal regeneration XIV thermally regenerable resin systems with high capacities. Desalination 34, 171–188 (1980).
Karabelas, A. J., Koutsou, C. P., Kostoglou, M. & Sioutopoulos, D. C. Analysis of specific energy consumption in reverse osmosis desalination processes. Desalination 431, 15–21 (2018).
Zhang, Y. Z. et al. Fit-for-purpose block polymer membranes molecularly engineered for water treatment. NPJ Clean Water 1, 2 (2018).
Zodrow, K. R. et al. Advanced materials, technologies, and complex systems analyses: emerging opportunities to enhance urban water security. Environ. Sci. Technol. 51, 10274–10281 (2017).
This work is supported by the Australia Research Council (project no. LP160101228). We thank the staff of the Monash Centre for Electron Microscopy (MCEM) for their technical support and assistance with the electron microscopy.
The authors declare no competing interests.
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Ou, R., Zhang, H., Truong, V.X. et al. A sunlight-responsive metal–organic framework system for sustainable water desalination. Nat Sustain 3, 1052–1058 (2020). https://doi.org/10.1038/s41893-020-0590-x
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