Macroscopic properties of materials stem from fundamental atomic-scale details, yet for insulators, resolving surface structures remains a challenge. We imaged the basal (0001) plane of α-aluminum oxide (α-AlO) using noncontact atomic force microscopy with an atomically defined tip apex. The surface formed a complex ([Formula: see text] × [Formula: see text])±9° reconstruction. The lateral positions of the individual oxygen and aluminum surface atoms come directly from experiment; we determined with computational modeling how these connect to the underlying crystal bulk. Before the restructuring, the surface Al atoms assume an unfavorable, threefold planar coordination; the reconstruction allows a rehybridization with subsurface O that leads to a substantial energy gain. The reconstructed surface remains stoichiometric, AlO.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1126/science.adq4744 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Small-angle neutron scattering differentiates molecular-level structural models of nanoparticle interfaces.
Nanoscale
January 2025
Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
The highly anisotropic and nonadditive nature of nanoparticle surfaces restricts their characterization by limited types of techniques that can reach atomic or molecular resolution. While small-angle neutron scattering (SANS) is a unique tool for analyzing complex systems, it has been traditionally considered a low-resolution method due to its limited scattering vector range and wide wavelength spread. In this article, we present a novel perspective on SANS by showcasing its exceptional capability to provide molecular-level insights into nanoparticle interfaces.
View Article and Find Full Text PDFReactivity and Mechanism of Recoverable Pd@CN Single-Atom Catalyst in Buchwald-Hartwig Aminations.
ACS Catal
January 2025
Institute of Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg, 1, 8093 Zurich, Switzerland.
Buchwald-Hartwig (BH) aminations are crucial for synthesizing arylamine motifs in numerous bioactive molecules and fine chemicals. While homogeneous palladium complexes can be effective catalysts, their high costs and environmental impact motivate the search for alternative approaches. Heterogeneous palladium single-atom catalysts (SAC) offer promising recoverable alternatives in C-C cross-couplings.
View Article and Find Full Text PDFSymmetrical and asymmetrical surface structure expansions of silver nanoclusters with atomic precision.
Chem Sci
January 2025
Department of Chemistry, Centre for Atomic Engineering of Advanced Materials, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Institutes of Physical Science and Information Technology, Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials, Anhui University Hefei Anhui 230601 China
Controlling symmetrical or asymmetrical growth has allowed a series of novel nanomaterials with prominent physicochemical properties to be produced. However, precise and continuous size growth based on a preserved template has long been a challenging pursuit, yet little has been achieved in terms of manipulation at the atomic level. Here, a correlated silver cluster series has been established, enabling atomically precise manipulation of symmetrical and asymmetrical surface structure expansions of metal nanoclusters.
View Article and Find Full Text PDFResolving the Nanostructure of Carbon Nitride-Supported Single-Atom Catalysts.
Small
January 2025
Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Piazza Leonardo da Vinci 32, Milano, 20133, Italy.
Single-atom catalysts (SACs) are gathering significant attention in chemistry due to their unique properties, offering uniform active site distribution and enhanced selectivity. However, their precise structure often remains unclear, with multiple models proposed in the literature. Understanding the coordination environment of the active site at the atomic level is crucial for explaining catalytic activity.
View Article and Find Full Text PDFCost-Effective RuNi Solid Solutions Prepared by Electrodeposition for Efficient Alkaline Hydrogen Evolution.
Small
January 2025
School of Materials Science and Engineering, Harbin Institute of Technology, Shenzhen, 518055, China.
The development of efficient hydrogen evolution reaction (HER) catalysts is crucial for water electrolysis. Currently, Ru-based catalysts are considered top contenders, but issues with stability, activity, and cost remain. In this work, RuNi alloys possessing a solid solution structure within the Ru lattice are prepared via straightforward electrodeposition on various substrates and assessed as HER catalysts in alkaline media.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!