Disentangling the size-dependent geometric and electronic effects of palladium nanocatalysts beyond selectivity

The prominent size effect of metal nanoparticles shapes decisively nanocatalysis, but entanglement of the corresponding geometric and electronic effects prevents exploiting their distinct functionalities. In this work, we demonstrate that in palladium (Pd)–catalyzed aerobic oxidation of benzyl alcohol, the geometric and electronic effects interplay and compete so intensively that both activity and selectivity showed in volcano trends on the Pd particle size unprecedentedly. By developing a strategy of site-selective blocking via atomic layer deposition along with first principles calculations, we disentangle these two effects and unveil that the geometric effect dominates the right side of the volcano with larger-size Pd particles, whereas the electronic effect directs the left of the volcano with smaller-size Pd particles substantially. Selective blocking of the low-coordination sites prevents formation of the undesired by-product beyond the volcano relationship, achieving a remarkable benzaldehyde selectivity and activity at the same time for 4-nm Pd. Disentangling the geometric and electronic effects of metal nanoparticles opens a new dimension for rational design of catalysts.

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A first-principles study of the atomic layer deposition of ZnO on carboxyl functionalized carbon nanotubes: the role of water molecules

Physical Chemistry Chemical Physics ◽

10.1039/d0cp05283c ◽

2021 ◽

Vol 23 (5) ◽

pp. 3467-3478

Author(s):

J. I. Paez-Ornelas ◽

H. N. Fernández-Escamilla ◽

H. A. Borbón-Nuñez ◽

H. Tiznado ◽

Noboru Takeuchi ◽

...

Keyword(s):

First Principles ◽

Ligand Exchange ◽

Functional Group ◽

Atomic Layer ◽

High Reactivity ◽

Water Molecules ◽

Exchange Reactions ◽

Layer Deposition ◽

The Right

Atomic description of ALD in systems that combine large surface area and high reactivity is key for selecting the right functional group to enhance the ligand-exchange reactions.

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Boron Nitride as a Novel Support for Highly Stable Palladium Nanocatalysts by Atomic Layer Deposition

Nanomaterials ◽

10.3390/nano8100849 ◽

2018 ◽

Vol 8 (10) ◽

pp. 849 ◽

Cited By ~ 13

Author(s):

Matthieu Weber ◽

Cassandre Lamboux ◽

Bruno Navarra ◽

Philippe Miele ◽

Sandrine Zanna ◽

...

Keyword(s):

Boron Nitride ◽

Atomic Layer Deposition ◽

Photoelectron Spectroscopy ◽

High Surface ◽

High Surface Area ◽

Atomic Layer ◽

Average Diameter ◽

Transmission Electron Microscopy Analysis ◽

Layer Deposition ◽

Palladium Nanocatalysts

The ability to prepare controllable nanocatalysts is of great interest for many chemical industries. Atomic layer deposition (ALD) is a vapor phase technique enabling the synthesis of conformal thin films and nanoparticles (NPs) on high surface area supports and has become an attractive new route to tailor supported metallic NPs. Virtually all the studies reported, focused on Pd NPs deposited on carbon and oxide surfaces. It is, however, important to focus on emerging catalyst supports such as boron nitride materials, which apart from possessing high thermal and chemical stability, also hold great promises for nanocatalysis applications. Herein, the synthesis of Pd NPs on boron nitride (BN) film substrates is demonstrated entirely by ALD for the first time. X-ray photoelectron spectroscopy indicated that stoichiometric BN formed as the main phase, with a small amount of BNxOy, and that the Pd particles synthesized were metallic. Using extensive transmission electron microscopy analysis, we study the evolution of the highly dispersed NPs as a function of the number of ALD cycles, and the thermal stability of the ALD-prepared Pd/BN catalysts up to 750 °C. The growth and coalescence mechanisms observed are discussed and compared with Pd NPs grown on other surfaces. The results show that the nanostructures of the BN/Pd NPs were relatively stable up to 500 °C. Consequent merging has been observed when annealing the samples at 750 °C, as the NPs’ average diameter increased from 8.3 ± 1.2 nm to 31 ± 4 nm. The results presented open up exciting new opportunities in the field of catalysis.

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Low-Temperature ABC-Type Atomic Layer Deposition: Synthesis of Highly Uniform Ultrafine Supported Metal Nanoparticles

Angewandte Chemie ◽

10.1002/ange.200907168 ◽

2010 ◽

Vol 122 (14) ◽

pp. 2601-2605 ◽

Cited By ~ 3

Author(s):

Junling Lu ◽

Peter C. Stair

Keyword(s):

Low Temperature ◽

Atomic Layer Deposition ◽

Metal Nanoparticles ◽

Atomic Layer ◽

Layer Deposition ◽

Supported Metal Nanoparticles ◽

Highly Uniform ◽

Supported Metal

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Tuning the influence of metal nanoparticles on ZnO photoluminescence by atomic-layer-deposited dielectric spacer

Nanophotonics ◽

10.1515/nanoph-2012-0040 ◽

2013 ◽

Vol 2 (2) ◽

pp. 153-160 ◽

Cited By ~ 17

Author(s):

Monan Liu ◽

Rui Chen ◽

Giorgio Adamo ◽

Kevin F. MacDonald ◽

Edbert J. Sie ◽

...

Keyword(s):

Optical Properties ◽

Metal Nanoparticles ◽

Atomic Layer ◽

Semiconductor Nanostructures ◽

Enhancement Ratio ◽

Local Surface ◽

Light Emitting ◽

Layer Deposition ◽

Dielectric Spacer ◽

Spacer Thickness

AbstractThere is increasing interest in tuning the optical and optoelectronic properties of semiconductor nanostructures using metal nanoparticles in their applications in light-emitting and detection devices. In this work we study the effect of a dielectric Al2O3 gap layer (i.e., spacer) on the interaction of ZnO nanowires with metal nanoparticles. The Al2O3 spacer thickness is varied in the range of 1–25 nm using atomic layer deposition (ALD) in order to tune the interaction. It is found that ~5 nm is an optimum spacer thickness common for most metals, although the enhancement ratio of the near-bandedge emission differs among the metals. Consistent results are obtained from both photoluminescence (PL) and cathodoluminescence (CL) spectroscopies, with the latter being applied to the optical properties of individual semiconductor/metal nanoheterostructures. The interaction is primarily proposed to be related to coupling of ZnO excitons with local surface plasmons of metals, although other mechanisms should not be ruled out.

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Ultralow loading palladium nanocatalysts prepared by atomic layer deposition on three-dimensional graphite-coated nickel foam to enhance the ethanol electro-oxidation reaction

RSC Advances ◽

10.1039/c5ra24546j ◽

2016 ◽

Vol 6 (16) ◽

pp. 13207-13216 ◽

Cited By ~ 4

Author(s):

Yiwu Jiang ◽

Jinwei Chen ◽

Jie Zhang ◽

Anqi Li ◽

Yaping Zeng ◽

...

Keyword(s):

Atomic Layer Deposition ◽

Palladium Nanoparticles ◽

Oxidation Reaction ◽

Nickel Foam ◽

Three Dimensional ◽

Atomic Layer ◽

Layer Deposition ◽

Palladium Nanocatalysts ◽

Electro Oxidation ◽

Deposition Technology

Ultralow loading palladium nanoparticles were facilely synthesized on a three-dimensional graphite-coated nickel foam support by metal atomic layer deposition technology and used as a promising catalyst for ethanol electro-oxidation reaction.

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Atomic layer deposited Pt-Ru dual-metal dimers and identifying their active sites for hydrogen evolution reaction

Nature Communications ◽

10.1038/s41467-019-12887-y ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 54

Author(s):

Lei Zhang ◽

Rutong Si ◽

Hanshuo Liu ◽

Ning Chen ◽

Qi Wang ◽

...

Keyword(s):

Hydrogen Evolution ◽

Active Sites ◽

Rational Design ◽

Atomic Layer ◽

Single Atom ◽

Structure Model ◽

Layer Deposition ◽

Dual Metal ◽

X Ray Absorption ◽

Excellent Stability

Abstract Single atom catalysts exhibit particularly high catalytic activities in contrast to regular nanomaterial-based catalysts. Until recently, research has been mostly focused on single atom catalysts, and it remains a great challenge to synthesize bimetallic dimer structures. Herein, we successfully prepare high-quality one-to-one A-B bimetallic dimer structures (Pt-Ru dimers) through an atomic layer deposition (ALD) process. The Pt-Ru dimers show much higher hydrogen evolution activity (more than 50 times) and excellent stability compared to commercial Pt/C catalysts. X-ray absorption spectroscopy indicates that the Pt-Ru dimers structure model contains one Pt-Ru bonding configuration. First principle calculations reveal that the Pt-Ru dimer generates a synergy effect by modulating the electronic structure, which results in the enhanced hydrogen evolution activity. This work paves the way for the rational design of bimetallic dimers with good activity and stability, which have a great potential to be applied in various catalytic reactions.

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(Invited) A Rational Design for Batteries at Nanoscale by Atomic Layer Deposition

ECS Transactions ◽

10.1149/06907.0023ecst ◽

2015 ◽

Vol 69 (7) ◽

pp. 23-30 ◽

Cited By ~ 3

Author(s):

C. Liu ◽

E. Gillette ◽

X. Chen ◽

A. J. Pearse ◽

A. C. Kozen ◽

...

Keyword(s):

Atomic Layer Deposition ◽

Rational Design ◽

Atomic Layer ◽

Layer Deposition

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Long-life lithium-sulfur batteries with high areal capacity based on coaxial CNTs@TiN-TiO2 sponge

Nature Communications ◽

10.1038/s41467-021-24976-y ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Hui Zhang ◽

Luis K. Ono ◽

Guoqing Tong ◽

Yuqiang Liu ◽

Yabing Qi

Keyword(s):

Rational Design ◽

Specific Capacity ◽

Three Dimensional ◽

Atomic Layer ◽

Catalyst System ◽

Lithium Sulfur Battery ◽

Layer Deposition ◽

Sulfur Battery ◽

Areal Capacity ◽

Lithium Sulfur

AbstractRational design of heterostructures opens up new opportunities as an ideal catalyst system for lithium polysulfides conversion in lithium-sulfur battery. However, its traditional fabrication process is complex, which makes it difficult to reasonably control the content and distribution of each component. In this work, to rationally design the heterostructure, the atomic layer deposition is utilized to hybridize the TiO2-TiN heterostructure with the three-dimensional carbon nanotube sponge. Through optimizing the deposited thickness of TiO2 and TiN layers and adopting the annealing post-treatment, the derived coaxial sponge with uniform TiN-TiO2 heterostructure exhibits the best catalytic ability. The corresponding lithium-sulfur battery shows enhanced electrochemical performance with high specific capacity of 1289 mAh g−1 at 1 C and capacity retention of 85% after 500 cycles at 2 C. Furthermore, benefiting from the highly porous structure and interconnected conductive pathways from the sponge, its areal capacity reaches up to 21.5 mAh cm−2.

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