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Selective electrochemical two-electron oxygen reduction is a promising route for renewable and on-site H2O2 generation as an alternative to the anthraquinone process. Herein, we report a high-performance nitrogen-coordinated single-atom Pd electrocatalyst, which is derived from Pd-doped zeolitic imidazolate frameworks (ZIFs) through one-step thermolysis. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) combined with X-ray absorption spectroscopy verifies atomically dispersed Pd atoms on nitrogen-doped carbon (Pd-NC). The single-atom Pd-NC catalyst exhibits excellent electrocatalytic performance for two-electron oxygen reduction to H2O2, which shows ∼95% selectivity toward H2O2 and an unprecedented onset potential of ∼0.8 V versus revisable hydrogen electrode (RHE) in 0.1 M KOH. Density functional theory (DFT) calculations demonstrate that the Pd-N4 catalytic sites thermodynamically prefer *–O bond breaking to O–O bond breaking, corresponding to a high selectivity for H2O2 production. This work provides a deep insight into the understanding of the catalytic process and design of high-performance 2e– ORR catalysts.
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This content will become publicly available on January 3, 2026
Sulfenylnitrene-mediated nitrogen-atom insertion for late-stage skeletal editing of N -heterocycles
Given the prevalence of nitrogen-containing heterocycles in commercial drugs, selectively incorporating a single nitrogen atom is a promising scaffold hopping approach to enhance chemical diversity in drug discovery libraries. We harness the distinct reactivity of sulfenylnitrenes, which insert a single nitrogen atom to transform readily available pyrroles, indoles, and imidazoles into synthetically challenging pyrimidines, quinazolines, and triazines, respectively. Our additive-free method for skeletal editing employs easily accessible, benchtop-stable sulfenylnitrene precursors over a broad temperature range (−30 to 150°C). This approach is compatible with diverse functional groups, including oxidation-sensitive functionalities such as phenols and thioethers, and has been applied to various natural products, amino acids, and pharmaceuticals. Furthermore, we have conducted mechanistic studies and explored regioselectivity outcomes through density functional theory calculations.
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- Award ID(s):
- 1753187
- PAR ID:
- 10577433
- Publisher / Repository:
- American Association for the Advancement of Science (AAAS)
- Date Published:
- Journal Name:
- Science
- Volume:
- 387
- Issue:
- 6729
- ISSN:
- 0036-8075
- Page Range / eLocation ID:
- 102 to 107
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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