Proton shuttle-assisted triplet energy transfer

Nature Materials (2026)Cite this article Electronic transition/motion coupled with proton transfer has a key role in natural and artificial energy conversion and storage materials. Previous examples include proton-coupled electron transfer and singlet energy transfer, but not triplet energy transfer. Here we report a mechanism termed proton shuttle-assisted triplet energy transfer. The system comprises ZnSe-based quantum dots surface anchored with phenol–pyridine dyadic acceptors. Ultrafast measurements and kinetic isotope effects establish that the photoexcitation of ZnSe leads to hole transfer from ZnSe to phenol, which is coupled with proton transfer from phenol to pyridine. A subsequent step of electron transfer from ZnSe to phenoxyl radical, coupled with back proton transfer from pyridinium, accomplishes a net process of spin-triplet migration from ZnSe to phenol–pyridine. Adding a strongly electron-withdrawing trifluoromethyl substituent on pyridine can switch the sequence of proton-coupled electron and hole transfer steps. Compared with a methylated analogue acceptor lacking the shuttle, the assistance of proton shuttle substantially increases the energy transfer rate and efficiency.This is a preview of subscription content, access via your institution Access Nature and 54 other Nature Portfolio journals Get Nature+, our best-value online-access subscription $32.99 / 30 days cancel any timeSubscribe to this journal Receive 12 print issues and online access $259.00 per yearonly $21.58 per issueBuy this articleUSD 39.95Prices may be subject to local taxes which are calculated during checkoutAll data are available in the Article or its Supplementary Information, and available from the corresponding author on request. They are also available via Figshare at https://doi.org/10.6084/m9.figshare.31249414. 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Fan for help with the nanosecond TA measurements; and R. Liu for the density functional theory calculations. K.W. thanks S. Hammes-Schiffer and K. Cui at Princeton University for discussion on the proton wavefunctions, and P. Zhou at Dalian Institute of Chemical Physics for the initial calculation of the excited-state energies.State Key Laboratory of Chemical Reaction Dynamics and New Cornerstone Science Laboratory, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, ChinaZhaolong Wang, Jingyi Zhu & Kaifeng WuUniversity of Chinese Academy of Sciences, Beijing, ChinaKaifeng WuSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarK.W. and Z.W. conceived the idea of this study. K.W. supervised the project. Z.W. synthesized the QDs and molecules and performed the spectroscopy measurements. J.Z. calculated the proton wavefunctions. K.W. and Z.W. analysed the data and wrote the manuscript with inputs from all authors.Correspondence to Kaifeng Wu.The authors declare no competing interests.Nature Materials thanks Sharon Hammes-Schiffer and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.Supplementary Notes 1–9, Supplementary Figs. 1–55, Supplementary Tables 1–8 and Supplementary References.Source data for Fig. 2.Source data for Fig. 3.Source data for Fig. 4.Source data for Fig. 5.Source data for Fig. 6.Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.Reprints and permissionsWang, Z., Zhu, J. & Wu, K. Proton shuttle-assisted triplet energy transfer. Nat. Mater. (2026). https://doi.org/10.1038/s41563-026-02535-4Download citationReceived: 06 May 2025Accepted: 08 February 2026Published: 09 March 2026Version of record: 09 March 2026DOI: https://doi.org/10.1038/s41563-026-02535-4Anyone you share the following link with will be able to read this content:Sorry, a shareable link is not currently available for this article. Provided by the Springer Nature SharedIt content-sharing initiative