Abstract
Catalyst-free production of H2O2 at hydrophobe–water micro-interfaces provides a sustainable synthesis route, yet its scalability remains challenging. We demonstrate that hydrophobic macroporous resins (MPRs) can serve as robust, metal-free platforms to construct scalable hydrophobic solid–water interfaces for continuous H2O2 generation, achieving a mass-normalized production rate of H2O2 as ~0.51 μmol gMPR-1 h-1 and eventually ~1 mM-level accumulation of H2O2 after one week’s stirring of the resin suspension under ambient atmosphere. Both macroporosity and hydrophobicity of MPRs are essential for the activity, and scale-up 1000 mL confirms practical feasibility. Mechanistic studies indicate that H2O2 forms predominantly via the oxygen reduction reaction (ORR), optimally at pH 9. This process requires no external light or electrical energy input, exhibits high salt tolerance, and is potentially compatible with renewable power sources. This work exemplifies how porous materials can enable sustainable, scalable chemical synthesis and updates the fundamental understanding of the micro-interface reactivity.
Data availability
All data that support the findings of this study are available from the corresponding author upon request. Source data are provided with this paper.
References
Du, Q., Superfine, R., Freysz, E. & Shen, Y. R. Vibrational spectroscopy of water at the vapor/water interface. Phys. Rev. Lett. 70, 2313–2316 (1993).
Björneholm, O. et al. Water at interfaces. Chem. Rev. 116, 7698–7726 (2016).
Ruiz-Lopez, M. F., Francisco, J. S., Martins-Costa, M. T. C. & Anglada, J. M. Molecular reactions at aqueous interfaces. Nat. Rev. Chem. 4, 459–475 (2020).
Shi, L. et al. Water structure and electric fields at the interface of oil droplets. Nature 640, 87–93 (2025).
Pullanchery, S., Kulik, S., Rehl, B., Hassanali, A. & Roke, S. Charge transfer across C–H⋅⋅⋅O hydrogen bonds stabilizes oil droplets in water. Science 374, 1366–1370 (2021).
Xiong, H., Lee, J. K., Zare, R. N. & Min, W. Strong electric field observed at the interface of aqueous microdroplets. J. Phys. Chem. Lett. 11, 7423–7428 (2020).
Xing, D. et al. Capture of hydroxyl radicals by hydronium cations in water microdroplets. Angew. Chem. Int. Ed. 61, e202207587 (2022).
Lee, J. K. et al. Spontaneous generation of hydrogen peroxide from aqueous microdroplets. Proc. Natl. Acad. Sci. USA 116, 19294–19298 (2019).
Lee, J. K. et al. Condensing water vapor to droplets generates hydrogen peroxide. Proc. Natl. Acad. Sci. USA 117, 30934–30941 (2020).
Mehrgardi, M. A., Mofidfar, M. & Zare, R. N. Sprayed water microdroplets are able to generate hydrogen peroxide spontaneously. J. Am. Chem. Soc. 144, 7606–7609 (2022).
Chen, C. J. & Williams, E. R. Are hydroxyl radicals spontaneously generated in unactivated water droplets? Angew. Chem. Int. Ed. 63, e202407433 (2024).
Eatoo, M. A. & Mishra, H. Disentangling the roles of dissolved oxygen, common salts, and pH on spontaneous hydrogen peroxide production in water: no O₂, no H₂O₂. J. Am. Chem. Soc. 147, 35392–35400 (2025).
Shirley, J. C. et al. Reevaluating anomalous electric fields at the air-water interface: a surface-specific spectroscopic survey. J. Am. Chem. Soc. 147, 46163–46173 (2025).
LaCour, R. A., Heindel, J. P., Zhao, R. & Head-Gordon, T. The role of interfaces and charge for chemical reactivity in microdroplets. J. Am. Chem. Soc. 147, 6299–6317 (2025).
Li, K. et al. Spontaneous dark formation of OH radicals at the interface of aqueous atmospheric droplets. Proc. Natl. Acad. Sci. USA 120, e2220228120 (2023).
Angelaki, M., Carreira Mendes Da Silva, Y., Perrier, S. & George, C. Quantification and mechanistic investigation of the spontaneous H₂O₂ generation at the interfaces of salt-containing aqueous droplets. J. Am. Chem. Soc. 146, 8327–8334 (2024).
Heindel, J. P., Hao, H., LaCour, R. A. & Head-Gordon, T. Spontaneous formation of hydrogen peroxide in water microdroplets. J. Phys. Chem. Lett. 13, 10035–10041 (2022).
Hao, H., Leven, I. & Head-Gordon, T. Can electric fields drive chemistry for an aqueous microdroplet? Nat. Commun. 13, 280 (2022).
Chen, X. et al. Hydrocarbon degradation by contact with anoxic water microdroplets. J. Am. Chem. Soc. 145, 21538–21545 (2023).
Xue, L. et al. Catalyst-free oxidation of styrene to styrene oxide using circulating microdroplets in an oxygen atmosphere. J. Am. Chem. Soc. 146, 26909–26915 (2024).
Wei, Z., Li, Y., Cooks, R. G. & Yan, X. Accelerated reaction kinetics in microdroplets: overview and recent developments. Annu. Rev. Phys. Chem. 71, 31–51 (2020).
Vannoy, K. J., Edwards, M. Q., Renault, C. & Dick, J. E. An electrochemical perspective on reaction acceleration in microdroplets. Annu. Rev. Anal. Chem. 17, 149–171 (2024).
Lee, J. K., Samanta, D., Nam, H. G. & Zare, R. N. Spontaneous formation of gold nanostructures in aqueous microdroplets. Nat. Commun. 9, 1562 (2018).
Yuan, X., Zhang, D., Liang, C. & Zhang, X. Spontaneous reduction of transition metal ions by one electron in water microdroplets and the atmospheric implications. J. Am. Chem. Soc. 145, 2800–2805 (2023).
Xia, D. et al. Spontaneous degradation of the “forever chemicals” perfluoroalkyl and polyfluoroalkyl substances (pfass) on water droplet surfaces. J. Am. Chem. Soc. 146, 11266–11271 (2024).
Jiang, Q. et al. Rapid N₂O formation from N₂ on water droplet surfaces. Angew. Chem. Int. Ed. 64, e202421002 (2025).
Li, J., Xia, Y., Song, X., Chen, B. & Zare, R. N. Continuous ammonia synthesis from water and nitrogen via contact electrification. Proc. Natl. Acad. Sci. USA 121, e2318408121 (2024).
Nguyen, D., Lyu, P. & Nguyen, S. C. Experimental and thermodynamic viewpoints on claims of a spontaneous H₂O₂ formation at the air–water interface. J. Phys. Chem. B 127, 2323–2330 (2023).
Campos-Martin, J. M., Blanco-Brieva, G. & Fierro, J. L. G. Hydrogen peroxide synthesis: an outlook beyond the anthraquinone process. Angew. Chem. Int. Ed. 45, 6962–6984 (2006).
Zhou, K. et al. Deciphering the kinetics of spontaneous generation of H₂O₂ in individual water microdroplets. J. Am. Chem. Soc. 146, 2445–2451 (2024).
Sun, M., Lu, Q., Wang, Z. L. & Huang, B. Understanding contact electrification at liquid-solid interfaces from surface electronic structure. Nat. Commun. 12, 1752 (2021).
Kim, Y., Ding, H. & Zheng, Y. Investigating water/oil interfaces with opto-thermophoresis. Nat. Commun. 13, 3742 (2022).
Lee, K. et al. Microdroplet-mediated radical polymerization. ACS Cent. Sci. 8, 1265–1271 (2022).
Musskopf, N. H., Gallo, A. Jr., Zhang, P., Petry, J. & Mishra, H. The air–water interface of water microdroplets formed by ultrasonication or condensation does not produce H₂O₂. J. Phys. Chem. Lett. 12, 11422–11429 (2021).
Nguyen, D. & Nguyen, S. C. Revisiting the effect of the air–water interface of ultrasonically atomized water microdroplets on H₂O₂ formation. J. Phys. Chem. B 126, 3180–3185 (2022).
Gallo, A. Jr et al. On the formation of hydrogen peroxide in water microdroplets. Chem. Sci. 13, 2574–2583 (2022).
Zhao, J. et al. Contact-electro-catalysis for direct synthesis of H₂O₂ under ambient conditions. Angew. Chem. Int. Ed. 62, e202300604 (2023).
Berbille, A. et al. Mechanism for generating H₂O₂ at water-solid interface by contact-electrification. Adv. Mater. 35, 2304387 (2023).
Lee, K., Bose, S., Song, X., Choi, S. Q. & Zare, R. N. Continuous flow contact electrocatalysis for hydrogen peroxide production. J. Phys. Chem. C 129, 6254–6261 (2025).
Wang, Z., Dong, X., Tang, W. & Wang, Z. L. Contact-electro-catalysis (CEC). Chem. Soc. Rev. 53, 4349–4373 (2024).
Wang, Z. et al. A contact-electro-catalysis process for producing reactive oxygen species by ball milling of triboelectric materials. Nat. Commun. 15, 757 (2024).
Wang, Z. et al. Contact-electro-catalysis for the degradation of organic pollutants using pristine dielectric powders. Nat. Commun. 13, 130 (2022).
Aiken, G. R., Thurman, E. M., Malcolm, R. L. & Walton, H. F. Comparison of XAD macroporous resins for the concentration of fulvic acid from aqueous solution. Anal. Chem. 51, 1799–1803 (1979).
Kim, J., Kim, D., Gwon, Y. J., Lee, K.-W. & Lee, T. S. Removal of sodium dodecylbenzenesulfonate by macroporous adsorbent resins. Materials 11, 1324 (2018).
Shi, C. et al. Preparation of macroporous high adsorbent resin and its application for heavy metal ion removal. ChemistrySelect 6, 9038–9045 (2021).
Zhou, M., Diwu, Z., Panchuk-Voloshina, N. & Haugland, R. P. A stable nonfluorescent derivative of resorufin for the fluorometric determination of trace hydrogen peroxide: applications in detecting the activity of phagocyte NADPH oxidase and other oxidases. Anal. Biochem. 253, 162–168 (1997).
Kakeshpour, T. & Bax, A. NMR characterization of H₂O₂ hydrogen exchange. J. Magn. Reson. 333, 107092 (2021).
Cassie, A. B. D. & Baxter, S. Wettability of porous surfaces. Trans. Faraday Soc. 40, 546–550 (1944).
Whyman, G., Bormashenko, E. & Stein, T. The rigorous derivation of Young, Cassie–Baxter and Wenzel equations and the analysis of the contact angle hysteresis phenomenon. Chem. Phys. Lett. 450, 355–359 (2008).
Marmur, A., Della Volpe, C., Siboni, S., Amirfazli, A. & Drelich, J. W. Contact angles and wettability: towards common and accurate terminology. Surf. Innov. 5, 3–8 (2017).
Shi, Y. et al. Confined water–encapsulated activated carbon for capturing short-chain perfluoroalkyl and polyfluoroalkyl substances from drinking water. Proc. Natl. Acad. Sci. USA 120, e2219179120 (2023).
Eatoo, M. A. & Mishra, H. Busting the myth of spontaneous formation of H₂O₂ at the air–water interface: contributions of the liquid–solid interface and dissolved oxygen exposed. Chem. Sci. 15, 3093–3103 (2024).
Chen, B. et al. Water–solid contact electrification causes hydrogen peroxide production from hydroxyl radical recombination in sprayed microdroplets. Proc. Natl. Acad. Sci. USA 119, e2209056119 (2022).
Zhou, X., Du, S., Zhang, W. & Zheng, B. Deciphering the mechanism of hydrogen peroxide formation in ultrasound-mediated water-in-oil microdroplets. Chem. Sci. 16, 6450–6457 (2025).
Angelaki, M., d’Erceville, J., Donaldson, D. J. & George, C. pH affects the spontaneous formation of H₂O₂ at the air–water interfaces. J. Am. Chem. Soc. 146, 25889–25893 (2024).
Martins-Costa, M. T. & Ruiz-López, M. F. Probing solvation electrostatics at the air–water interface. Theor. Chem. Acc. 142, 29 (2023).
Gong, K. et al. Revisiting the enhanced chemical reactivity in water microdroplets: the case of a Diels-Alder reaction. J. Am. Chem. Soc. 146, 31585–31596 (2024).
Chen, C. J. & Williams, E. R. A source of the mysterious m/z 36 ions identified: implications for the stability of water and unusual chemistry in microdroplets. ACS Cent. Sci. 11, 622–628 (2025).
Chen, C. J. & Williams, E. R. An alternative explanation for ions put forth as evidence for abundant hydroxyl radicals formed due to the intrinsic electric field at the surface of water droplets. Anal. Chem. 97, 17687–17695 (2025).
Asserghine, A. et al. Dissolved oxygen redox as the source of hydrogen peroxide and hydroxyl radical in sonicated emulsive water microdroplets. J. Am. Chem. Soc. 147, 11851–11858 (2025).
Zhang, N., Wang, J., Ye, J., Zhao, P. & Xiao, M. Oxyalkylation modification as a promising method for preparing low-melting-point agarose. Int. J. Biol. Macromol. 117, 696–703 (2018).
Bowes, B. D. & Lenhoff, A. M. Protein adsorption and transport in dextran-modified ion-exchange media. III. Effects of resin charge density and dextran content on adsorption and intraparticle uptake. J. Chromatogr. A 1218, 7180–7188 (2011).
Li, Y., Pham, J. Q., Johnston, K. P. & Green, P. F. Contact angle of water on polystyrene thin films: effects of CO2 environment and film thickness. Langmuir 23, 9785–9793 (2007).
Brown, P. S. & Bhushan, B. Mechanically durable liquid-impregnated honeycomb surfaces. Sci. Rep. 7, 6083 (2017).
Bardestani, R., Patience, G. S. & Kaliaguine, S. Experimental methods in chemical engineering: specific surface area and pore size distribution measurements—BET, BJH, and DFT. Can. J. Chem. Eng. 97, 2781–2791 (2019).
Allanas, E., Rahman, A., Arlin, E. & Prasetyanto, E. A. Study surface area and pore size distribution on synthetic zeolite X using BET, BJH and DFT methods. J. Phys. Conf. Ser. 2019, 012094 (2021).
Acknowledgements
The authors acknowledge the financial support from the National Key Research and Development Program (No. 2024FYA1509600, W.W.) and the National Natural Science Foundation of China (Nos. 22474060, H.S.; 22327803, W.W.).
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All authors have approved the final version of the manuscript. H.S., Z.B.Z., and W.W. designed the project. H.S., J.G., and W.W. wrote the paper. J.G., K.Z., and H.S. carried out most of the experiments and analyzed the data. X.L.G., K.R.Y., and S.Y.Y. participated in discussing the manuscript. W.W. conceived and supervised the project.
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Nature Communications thanks Himanshu Mishra, who co-reviewed with Muzzamil Eatoo, Ryan Sullivan, and Richard Zare for their contribution to the peer review of this work. A peer review file is available.
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Gao, J., Zhou, K., Guo, X. et al. Constructing scalable hydrophobe–water micro-interfaces for catalyst-free generation of H2O2 via macroporous resins. Nat Commun (2026). https://doi.org/10.1038/s41467-026-69085-w
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DOI: https://doi.org/10.1038/s41467-026-69085-w
