Equilibrium shapes and triple line energy of epitaxial gold nanocrystals supported on<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mtext>TiO</mml:mtext></mml:mrow><mml:mn>2</mml:mn></mml:msub><mml:mrow><mml:mo>(</mml:mo><mml:mrow><mml:mn>110</mml:mn></mml:mrow><mml:mo>)</mml:mo></mml:mrow></mml:mrow></mml:math>

Sivaramakrishnan, S.; Wen, Jianguo; Scarpelli, Michael. E.; Pierce, Benjamin J.; Zuo, Jian‐Min

doi:10.1103/physrevb.82.195421

Cited by 37 publications

(33 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…An example of this is shown in figure 25 where the results indicate a size-dependent Wulff shape. The authors [190] attributed this to the triple-junction line tension having a role at very small sizes although it is not clear to us whether this might not be a consequence of misfit strain. For completeness, we should mention that it has been known since the early work on epitaxy that nanoparticles often nucleate at steps, so there can be further deviations away from the Winterbottom shape as recently pointed out by Gao et al [193].…”

Section: The Effect Of Size Dependent Strainmentioning

confidence: 91%

“…The thermodynamic minimum energy shape minimizes not only the external surface energy but also the interface strain energy so will deviate from the Winterbottom shape [187][188][189], and it may also be important to include line energy terms for the vacuum/substrate/nanoparticle three-phase interface (e.g. [190][191][192].). An example of this is shown in figure 25 where the results indicate a size-dependent Wulff shape.…”

Section: The Effect Of Size Dependent Strainmentioning

confidence: 99%

See 1 more Smart Citation

Nanoparticle shape, thermodynamics and kinetics

Marks

Peng

2016

J. Phys.: Condens. Matter

245

274

View full text Add to dashboard Cite

Nanoparticles can be beautiful, as in stained glass windows, or they can be ugly as in wear and corrosion debris from implants. We estimate that there will be about 70,000 papers in 2015 with nanoparticles as a keyword, but only one in thirteen uses the nanoparticle shape as an additional keyword and research focus, and only one in two hundred has thermodynamics. Methods for synthesizing nanoparticles have exploded over the last decade, but our understanding of how and why they take their forms has not progressed as fast. This topical review attempts to take a critical snapshot of the current understanding, focusing more on methods to predict than a purely synthetic or descriptive approach. We look at models and themes which are largely independent of the exact synthetic method whether it is deposition, gas-phase condensation, solution based or hydrothermal synthesis. Elements are old dating back to the beginning of the 20th century-some of the pioneering models developed then are still relevant today. Others are newer, a merging of older concepts such as kinetic-Wulff constructions with methods to understand minimum energy shapes for particles with twins. Overall we find that while there are still many unknowns, the broad framework of understanding and predicting the structure of nanoparticles via diverse Wulff constructions, either thermodynamic, local minima or kinetic has been exceedingly successful. However, the field is still developing and there remain many unknowns and new avenues for research, a few of these being suggested towards the end of the review.

show abstract

Section: The Effect Of Size Dependent Strainmentioning

confidence: 91%

Section: The Effect Of Size Dependent Strainmentioning

confidence: 99%

Nanoparticle shape, thermodynamics and kinetics

Marks

Peng

2016

J. Phys.: Condens. Matter

245

274

View full text Add to dashboard Cite

show abstract

“…We follow previously reported procedures of Au deposition and annealing to promote epitaxial nanocrystal formation 25,28,41,42 (see Supporting Information for more details). After the Au nanocrystals were formed, no further TEM sample preparation procedures were needed.…”

mentioning

confidence: 99%

“…It is capable of resolving atoms separated by 1 Å. 28 The sizes of the Au nanocrystals ranged from 3.5−12 nm in width depending on the annealing conditions. Figure 1, panels a and c show two Z-contrast images using a high angle ADF detector (inner cutoff angle at 100 mrad) along TiO 2 [001] (Au [110]).…”

mentioning

confidence: 99%

Direct Observation of Interfacial Au Atoms on TiO₂ in Three Dimensions

et al. 2015

Self Cite

View full text Add to dashboard Cite

Interfacial atoms, which result from interactions between the metal nanoparticles and support, have a large impact on the physical and chemical properties of nanoparticles. However, they are difficult to observe; the lack of knowledge has been a major obstacle toward unraveling their role in chemical transformations. Here we report conclusive evidence of interfacial Au atoms formed on the rutile (TiO2) (110) surfaces by activation using high-temperature (∼500 °C) annealing in air. Three-dimensional imaging was performed using depth-sectioning enabled by aberration-corrected scanning transmission electron microscopy. Results show that the interface between Au nanocrystals and TiO2 (110) surfaces consists of a single atomic layer with Au atoms embedded inside Ti-O. The number of interfacial Au atoms is estimated from ∼1-8 in an interfacial atomic column. Direct impact of interfacial Au atoms is observed on an enhanced Au-TiO2 interaction and the reduction of surface TiO2; both are critical to Au catalysis.

show abstract

“…Despite enormous progress and widespread use during the last few decades, atomic-scale imaging techniques now described in textbooks [ 11 ], such as optical, electron, scanning tunneling and atomic force microspcopy, present technical difficulties and inherent resolution limitations. Accurate atomic-level nanostructure determination requires state-of the-art methods which often combine experimental techniques and nanoparticle modeling [ 12 , 13 ]. On the other hand, the quantum energies in metal nanoparticles are clearly affected by their shape [ 14 ] and the presence of adsorbates, as shown both theoretically [ 15 ] and experimentally [ 16 ].…”

Section: Introductionmentioning

confidence: 99%

Shape-Dependent Single-Electron Levels for Au Nanoparticles

2016

View full text Add to dashboard Cite

The shape of metal nanoparticles has a crucial role in their performance in heterogeneous catalysis as well as photocatalysis. We propose a method of determining the shape of nanoparticles based on measurements of single-electron quantum levels. We first consider nanoparticles in two shapes of high symmetry: cube and sphere. We then focus on Au nanoparticles in three characteristic shapes that can be found in metal/inorganic or metal/organic compounds routinely used in catalysis and photocatalysis. We describe the methodology we use to solve the Schrödinger equation for arbitrary nanoparticle shape. The method gives results that agree well with analytical solutions for the high-symmetry shapes. When we apply our method in realistic gold nanoparticle models, which are obtained from Wulff construction based on first principles calculations, the single-electron levels and their density of states exhibit distinct shape-dependent features. Results for clean-surface nanoparticles are closer to those for cubic particles, while CO-covered nanoparticles have energy levels close to those of a sphere. Thiolate-covered nanoparticles with multifaceted polyhedral shape have distinct levels that are in between those for sphere and cube. We discuss how shape-dependent electronic structure features could be identified in experiments and thus guide catalyst design.

show abstract

Equilibrium shapes and triple line energy of epitaxial gold nanocrystals supported onTiO2(110)

Cited by 37 publications

References 45 publications

Nanoparticle shape, thermodynamics and kinetics

Nanoparticle shape, thermodynamics and kinetics

Direct Observation of Interfacial Au Atoms on TiO₂ in Three Dimensions

Shape-Dependent Single-Electron Levels for Au Nanoparticles

Contact Info

Product

Resources

About

Equilibrium shapes and triple line energy of epitaxial gold nanocrystals supported onTiO2(110)

Cited by 37 publications

References 45 publications

Nanoparticle shape, thermodynamics and kinetics

Nanoparticle shape, thermodynamics and kinetics

Direct Observation of Interfacial Au Atoms on TiO2 in Three Dimensions

Shape-Dependent Single-Electron Levels for Au Nanoparticles

Contact Info

Product

Resources

About

Direct Observation of Interfacial Au Atoms on TiO₂ in Three Dimensions