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Fully exposed palladium cluster catalysts enable hydrogen production from nitrogen heterocycles


The size of supported metal species is known to have a profound influence on their catalytic activity. However, this structure sensitivity remains ambiguous for metals at the atomic scale due to the lack of single-atom sensitive and statistically significant quantification methods. Here we overcome this difficulty to quantify the catalytic contribution of various surface palladium species, ranging from single atoms to sub-nanometre clusters and nanoparticles, in the dehydrogenation of dodecahydro-N-ethylcarbazole, a reaction of importance for H2 transportation and utilization. We show that the optimal site is a fully exposed palladium cluster with an average Pd–Pd coordination number of 4.4, favouring both the activation of reactants and desorption of products, whereas palladium single atoms are almost inactive. Our study highlights that for certain catalytic reactions, the construction of fully exposed metal clusters without the presence of spectators (that is, palladium single atoms in this work) could help to maximize the reactivity and the atomic efficiency of noble metals.

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Fig. 1: Schematic of the process.
Fig. 2: Structures of different Pd/ND catalysts.
Fig. 3: Coordination and electronic properties of different Pd/ND catalysts.
Fig. 4: The dehydrogenation performance of different palladium catalysts/sites.
Fig. 5: DFT calculations of the palladium-catalysed DNEC dehydrogenation process.

Data availability

All data of this study are available from the corresponding authors upon reasonable request; source data are provided with this paper. Atomic coordinates of the computational studies are provided as Supplementary Data 1 with this paper. Source data are provided with this paper.


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This work received financial support from the Natural Science Foundation of China (21725301, 21932002, 22005007, 21821004), the National Key R&D Program of China (2021YFA1501100) and the Beijing Outstanding Young Scientist Program (BJJWZYJH01201914430039). C.D. acknowledges the China Postdoctoral Science Foundation (2018M640016). H.L. acknowledges the Liaoning Revitalization Talents Program (XLYC1907055). The X-ray absorption spectroscopy was conducted at the Shanghai Synchrotron Radiation Facility and the Beijing Synchrotron Radiation Facility. D.M. acknowledges support from the Tencent Foundation through the XPLORER PRIZE. Y.L. and Y.-G.W. were financially supported by the Natural Science Foundation of China (numbers 22022504, 22033005), the Guangdong ‘Pearl River’ Talent Plan (number 2019QN01L353), the Higher Education Innovation Strong School Project of Guangdong Province of China (number 2020KTSCX122) and the Guangdong Provincial Key Laboratory of Catalysis (number 2020B121201002). The computational resource is supported by the Center for Computational Science and Engineering at SUSTech and the CHEM high-performance supercomputer cluster (CHEM-HPC) located at the Department of Chemistry, SUSTech.

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Authors and Affiliations



D.M. conceived the project. D.M., Y.-G.W. and H.L. supervised the study. C.D., Z.G. and C.L. performed most of the reactions. F.H. and X.W. helped with the preparation of the catalysts. Y.L. and Y.-G.W. did the DFT calculations. M.P., Y.D., Y.X. and X.Q. performed the X-ray related characterizations (XAS, XPS) and analysis. M.W. and M.X. gave advice about the chemisorption and DRIFT analysis. Z.G. and W.Z. performed the electron microscopy study. C.D. and D.M. wrote the paper. All authors contributed to the discussion and revision of the paper.

Corresponding authors

Correspondence to Yang-Gang Wang, Hongyang Liu, Wu Zhou or Ding Ma.

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Nature Catalysis thanks Rhett Kempe and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary information

Supplementary Information

Supplementary methods, Figs. 1–22, Tables 1–7, Notes 1–6 and references

Supplementary Data 1

Electronic structure calculations.

Source data

Source Data Fig. 1

Graphical illustration.

Source Data Fig. 2

STEM images and DRIFT spectra.

Source Data Fig. 3

EXAFS and XPS spectra.

Source Data Fig. 4

Catalytic performance.

Source Data Fig. 5

Energy profiles.

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Dong, C., Gao, Z., Li, Y. et al. Fully exposed palladium cluster catalysts enable hydrogen production from nitrogen heterocycles. Nat Catal 5, 485–493 (2022).

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