Atomic‐Scale Mapping of Impurities in Partially Reduced Hollow TiO<sub>2</sub> Nanowires

Lim, Joohyun; Kim, Se‐Ho; Armengol, Raquel Aymerich; Kasian, Olga; Choi, Pyuck‐Pa; Stephenson, Leigh T.; Gault, Baptiste; Scheu, Christina

doi:10.1002/ange.201915709

Cited by 9 publications

(9 citation statements)

References 29 publications

(4 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For this analysis, we embedded the NPs in an electrodeposited Ni film via the method described in Refs. 39,40 ; then, needle-shaped specimens were obtained from this composite Pd NP-Ni film through focused ion beam (FIB) milling 41 . Supplementary Fig.…”

Section: Resultsmentioning

confidence: 99%

Three-dimensional atomic mapping of ligands on palladium nanoparticles by atom probe tomography

et al. 2021

View full text Add to dashboard Cite

Capping ligands are crucial to synthesizing colloidal nanoparticles with functional properties. However, the synergistic effect between different ligands and their distribution on crystallographic surfaces of nanoparticles during colloidal synthesis is still unclear despite powerful spectroscopic techniques, due to a lack of direct imaging techniques. In this study, atom probe tomography is adopted to investigate the three-dimensional atomic-scale distribution of two of the most common types of these ligands, cetrimonium (C19H42N) and halide (Br and Cl) ions, on Pd nanoparticles. The results, validated using density functional theory, demonstrate that the Br anions adsorbed on the nanoparticle surfaces promote the adsorption of the cetrimonium cations through electrostatic interactions, stabilizing the Pd {111} facets. In contrast, the Cl anions are not strongly adsorbed onto the Pd surfaces. The high density of adsorbed cetrimonium cations for Br anion additions results in the formation of multiple-twinned nanoparticles with superior oxidation resistance.

show abstract

Section: Resultsmentioning

confidence: 99%

Three-dimensional atomic mapping of ligands on palladium nanoparticles by atom probe tomography

et al. 2021

View full text Add to dashboard Cite

show abstract

“…The as-synthesized Au-Fe NPs were coelectrodeposited with Ni according to the protocol detailed in Ref. [59]. The dried Au-Fe NPs powder was dispersed in a Ni ion electrolyte followed by pouring the solution into a vertical electro-cell where a counter electrode (Pt mesh) was positioned on top, and a working electrode (Cu foil) placed on the bottom.…”

Section: Atom Probe Tomographymentioning

confidence: 99%

Multidimensional thermally-induced transformation of nest-structured complex Au-Fe nanoalloys towards equilibrium

et al. 2021

Self Cite

View full text Add to dashboard Cite

Bimetallic nanoparticles are often superior candidates for a wide range of technological and biomedical applications owing to their enhanced catalytic, optical, and magnetic properties, which are often better than their monometallic counterparts. Most of their properties strongly depend on their chemical composition, crystallographic structure, and phase distribution. However, little is known of how their crystal structure, on the nanoscale, transforms over time at elevated temperatures, even though this knowledge is highly relevant in case nanoparticles are used in, e.g., high-temperature catalysis. Au-Fe is a promising bimetallic system where the low-cost and magnetic Fe is combined with catalytically active and plasmonic Au. Here, we report on the in situ temporal evolution of the crystalline ordering in Au-Fe nanoparticles, obtained from a modern laser ablation in liquids synthesis. Our in-depth analysis, complemented by dedicated atomistic simulations, includes a detailed structural characterization by X-ray diffraction and transmission electron microscopy as well as atom probe tomography to reveal elemental distributions down to a single atom resolution. We show that the Au-Fe nanoparticles initially exhibit highly complex internal nested nanostructures with a wide range of compositions, phase distributions, and size-depended microstrains. The elevated temperature induces a diffusion-controlled recrystallization and phase merging, resulting in the formation of a single face-centered-cubic ultrastructure in contact with a body-centered cubic phase, which demonstrates the metastability of these structures. Uncovering these unique nanostructures with nested features could be highly attractive from a fundamental viewpoint as they could give further insights into the nanoparticle formation mechanism under non-equilibrium conditions. Furthermore, the in situ evaluation of the crystal structure changes upon heating is potentially relevant for high-temperature process utilization of bimetallic nanoparticles, e.g., during catalysis.

show abstract

“…The collected nanoparticles were coelectrodeposited with Ni according to the protocol detailed in ref. [39]. The dried FeRh NP powder was dispersed in a Ni ion electrolyte followed by pouring the solution into a vertical electro-cell where a counter electrode (Pt mesh) positioned on top and a working electrode (Cu foil) placed on bottom.…”

Section: Methodsmentioning

confidence: 99%

Controlling the Oxidation of Magnetic and Electrically Conductive Solid-Solution Iron-Rhodium Nanoparticles Synthesized by Laser Ablation in Liquids

et al. 2020

Self Cite

View full text Add to dashboard Cite

This study focuses on the synthesis of FeRh nanoparticles via pulsed laser ablation in liquid and on controlling the oxidation of the synthesized nanoparticles. Formation of monomodal γ-FeRh nanoparticles was confirmed by transmission electron microscopy (TEM) and their composition confirmed by atom probe tomography (APT). For these particles, three major contributors to oxidation were analysed: (1) dissolved oxygen in the organic solvents, (2) the bound oxygen in the solvent and (3) oxygen in the atmosphere above the solvent. The decrease of oxidation for optimized ablation conditions was confirmed through energy-dispersive X-ray (EDX) and Mössbauer spectroscopy. Furthermore, the time dependence of oxidation was monitored for dried FeRh nanoparticles powders using ferromagnetic resonance spectroscopy (FMR). By magnetophoretic separation, B2-FeRh nanoparticles could be extracted from the solution and characteristic differences of nanostrand formation between γ-FeRh and B2-FeRh nanoparticles were observed.

show abstract

Atomic‐Scale Mapping of Impurities in Partially Reduced Hollow TiO₂ Nanowires

Cited by 9 publications

References 29 publications

Three-dimensional atomic mapping of ligands on palladium nanoparticles by atom probe tomography

Three-dimensional atomic mapping of ligands on palladium nanoparticles by atom probe tomography

Multidimensional thermally-induced transformation of nest-structured complex Au-Fe nanoalloys towards equilibrium

Controlling the Oxidation of Magnetic and Electrically Conductive Solid-Solution Iron-Rhodium Nanoparticles Synthesized by Laser Ablation in Liquids

Contact Info

Product

Resources

About

Atomic‐Scale Mapping of Impurities in Partially Reduced Hollow TiO2 Nanowires

Cited by 9 publications

References 29 publications

Three-dimensional atomic mapping of ligands on palladium nanoparticles by atom probe tomography

Three-dimensional atomic mapping of ligands on palladium nanoparticles by atom probe tomography

Multidimensional thermally-induced transformation of nest-structured complex Au-Fe nanoalloys towards equilibrium

Controlling the Oxidation of Magnetic and Electrically Conductive Solid-Solution Iron-Rhodium Nanoparticles Synthesized by Laser Ablation in Liquids

Contact Info

Product

Resources

About

Atomic‐Scale Mapping of Impurities in Partially Reduced Hollow TiO₂ Nanowires