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Updated: Jan 28, 2026
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Identification of the Surface Hydrogen Functionalities on Colloidal Zinc Oxide Nanocrystals with Multinuclear
Guolong Sun1, Yijin Chen2, Xiaoli Xia3
1State Key Laboratory of Silicon and Advanced Semiconductor Materials, Zhejiang Key Laboratory of Excited-State Energy Conversion and Energy Storage, Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. China.
Journal of the American Chemical Society
|January 27, 2026
Summary
Advanced NMR and DFT revealed eight distinct surface hydrogen species on zinc oxide (ZnO) nanocrystals. This detailed understanding aids in designing functional ZnO nanomaterials.
Area of Science:
- Materials Science
- Nanotechnology
- Surface Chemistry
Background:
- Surface hydrogen species on zinc oxide (ZnO) nanocrystals are crucial for their properties but difficult to identify.
- Existing methods struggle with the complexity and disorder of nanocrystal surfaces.
Purpose of the Study:
- To comprehensively analyze and structurally identify surface functionalities on sol-gel synthesized ZnO nanocrystals.
- To understand the role and interactions of various surface hydrogen species.
Main Methods:
- Utilized advanced multinuclear and multidimensional solid-state nuclear magnetic resonance (NMR) spectroscopy (¹H, ⁷Li, ¹³C, ¹⁷O, ³¹P).
- Combined NMR with density functional theory (DFT) calculations.
- Employed deuterated precursors, ¹⁷O isotope labeling, probe molecules, defect analysis, and electron paramagnetic resonance (EPR).
Main Results:
- Resolved and assigned eight distinct surface hydrogen species, including acetate, lithium acetate, water (chemisorbed/physisorbed), terminal hydroxyls (OHT), tribridged hydroxyls (μ₃-OH), and defect-associated hydroxyls.
- ¹H-¹H homonuclear correlation SSNMR experiments revealed crystal facet selectivity and spatial interactions of these species.
Conclusions:
- Established an in-depth understanding of the diverse surface hydrogen landscape on ZnO nanocrystals.
- Provided a framework for rational design and functional tuning of ZnO-based nanomaterials.
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