Scanning tunnelling microscopy (STM) was used to investigate the nucleation and growth of palladium clusters on two different, ultrathin, epitaxial, titania films grown on a Pt3Ti(111) surface. The first oxide phase, z'-TiO x , is anisotropic and consists of parallel stripes separated by trenches. Defects (i.e., oxygen vacancies) in this structure are confined to these trenches and act as nucleation sites. Therefore, the Pd clusters are mostly arranged in unidirectional rows along the trenches, creating a template effect. The second phase, w'-TiO x , exhibits a hexagonal, long range, (7 × 7)R21.8°, Moiré-type superstructure with fewer and shallower defects, making the template effect less discernible.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4660946 | PMC |
| http://dx.doi.org/10.3762/bjnano.6.204 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Background: Neuropathological tau tangles in Alzerheimer's disease (AD) have been roughly characterized into pre-tangles, mature tangles and ghost tangles. However, to date, their maturation in the human brain is poorly understood. Here, we aimed to define the structure and composition of tangle maturation stages in the AD brain using correlative light and electron microscopy (CLEM).
View Article and Find Full Text PDFDFT Investigation of (X = Ni, Pd, and Pt) Clusters on Ultrathin Supported MgO Films: Evidence of Oxygen Spillover and Relevance for Catalytic Model Studies.
J Phys Chem C Nanomater Interfaces
December 2024
Department of Materials Science, University of Milano-Bicocca, Via Roberto Cozzi 55, 20125 Milano, Italy.
The adsorption of (X = Ni, Pd, and Pt) nanoclusters is simulated by using first-principles methods on MgO(100) and on a MgO monolayer supported on Ag(100), considering the presence of interfacial oxygen. On both the free-standing MgO surface and MgO/Ag, all clusters exhibit robust adhesion and negative charge transfer. molecular dynamics calculations at 200 K demonstrate the stability of the nanoparticles on the MgO/Ag support.
View Article and Find Full Text PDFHigh-Nuclearity Polyoxometalate-Based Metal-Organic Frameworks for Photocatalytic Oxidative Cleavage of C-C Bond.
Angew Chem Int Ed Engl
December 2024
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry and Chemical Engineering, Donghua University, Shanghai, 201620, P. R. China.
High-nuclearity polyoxometalate (POM) clusters are attractive building blocks (BBs) for the synthesis of metal-organic frameworks (MOFs) due to their high connectivity and inherently multiple metal centers as functional sites. This work demonstrates a strategy of step-wise growth on ring-shaped [PWO] precursor, which produced two new high-nuclearity polyoxotungstates, a half-closed [HPWO] {W} and a fully-closed [HPWO] {W}. By in situ synthesis, unique MOFs of copper triazole-benzoic acid (HL) complexes incorporating the negatively-charged {W} and {W} as nodes, {Cu(HL)W} HNPOMOF-1 and {Cu(HL)W} HNPOMOF-2, were constructed by delicately tuning the reaction conditions, mainly solution pH, which controls the formation of {W} and {W}, and at the same time the protonation of triazole-benzoic acid ligand thus its coordination mode to copper ion that creates the highest nuclearity POM-derived MOFs reported to date.
View Article and Find Full Text PDFSub-millielectronvolt Line Widths in Polarized Low-Temperature Photoluminescence of 2D PbS Nanoplatelets.
Nano Lett
December 2024
Institute of Solid State Physics, Leibniz University Hannover, Appelstraße 2, D-30167 Hannover, Germany.
Colloidal semiconductor nanocrystals are promising materials for classical and quantum light sources due to their efficient photoluminescence (PL) and versatile chemistry. While visible emitters are well-established, excellent (near-infrared) sources are still being pursued. We present the first comprehensive analysis of low-temperature PL from two-dimensional (2D) PbS nanoplatelets (NPLs).
View Article and Find Full Text PDFEvidence of Quasi-Na Metallic Clusters in Sodium Ion Batteries through In Situ X-Ray Diffraction.
Adv Mater
January 2025
Confucius Energy Storage Lab, School of Energy and Environment & Z Energy Storage Center, Southeast University, Nanjing, 211189, P. R. China.
Carbonaceous materials have been considered the most promising anode in sodium-ion batteries (SIBs) due to their low cost, good electrical conductivity, and structural stability. The main challenge of carbonaceous anodes prior to their commercialization is low initial coulomb efficiencies, derived from a lack of an efficient technique to reveal a fundamental comprehension of sodium storage mechanisms. Here, the direct observation of quasi-Na metallic clusters in carbonaceous anodes during cycling through in situ XRD is reported.
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!