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Ethylene glycol as an efficient and reversible liquid-organic hydrogen carrier


Hydrogen has long been regarded as an ideal alternative clean energy vector to overcome the drawbacks of fossil technology. However, the direct utilization of hydrogen is a challenge because of the low volumetric energy density of hydrogen gas and potential safety issues. Here we report an efficient and reversible liquid to liquid-organic hydrogen carrier system based on inexpensive, readily available and renewable ethylene glycol. This hydrogen storage system enables the efficient and reversible loading and discharge of hydrogen using a ruthenium pincer complex, with a theoretical hydrogen storage capacity of 6.5 wt%.

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Fig. 1: Development of a LOHC system based on ethylene glycol.
Fig. 2: Results of the catalytic acceptorless dehydrogenative coupling of EG.
Fig. 3: Results of the catalytic acceptorless dehydrogenative coupling of EG and the hydrogenation of the reaction mixture using dearomatized complex 10.
Fig. 4: Proposed catalytic cycle.
Fig. 5: Energy levels of the proposed catalytic cycle.

Data availability

The data that support the findings of this study are available from the corresponding author upon reasonable request.


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This research was supported by the European Research Council (ERC AdG 692775). D.M. holds the Israel Matz Professorial Chair of Organic Chemistry. Y.-Q.Z. and Y.X. acknowledge the Sustainability and Energy Research Initiative (SAERI) Weizmann Institute of Science for a research fellowship. N.v.W. is supported by the Foreign Postdoctoral Fellowship Program of the Israel Academy of Sciences and Humanities. N.v.W. thanks M. Iron (Department of Chemical Research Support) for fruitful discussions regarding the density functional theory calculations.

Author information




D.M. conceived and directed the project. Y.-Q.Z. and D.M. designed the experiments. Y.-Q.Z. performed and analysed the experiments. N.v.W. performed the computational studies. A.A. carried out pioneering studies on this project. Y.X. designed and built the gas-collecting system and provided useful discussions. Y.-Q.Z., N.v.W. and D.M. prepared the manuscript.

Corresponding author

Correspondence to David Milstein.

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Supplementary information

Supplementary Information

Supplementary Methods, Supplementary Figures 1–62, Supplementary Tables 1–3, Supplementary References

Structure calculations

Cartesian Coordinates of Computed Structures

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Zou, YQ., von Wolff, N., Anaby, A. et al. Ethylene glycol as an efficient and reversible liquid-organic hydrogen carrier. Nat Catal 2, 415–422 (2019).

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