A new bimetallic plasmonic photocatalyst consisting of gold(core)-copper(shell) nanoparticle and titanium(IV) oxide support

AbstractThe catalytic properties of nanostructured gold catalyst are known to depend on the size of the gold particles and to be activated when the size decreases to a few nanometers. We investigated the size dependence of the three-dimensional nanostructure on the mean inner potential of gold catalysts supported on titanium oxide using electron holography and high-resolution electron microscopy (HREM). The contact angle of the gold particles on the titanium oxide tended to be over 90° for gold particles with a size of over 5 nm, and below 90° for a size of below 2 nm. This decreasing change in the contact angle (morphology) acts to increase the perimeter and hence the area of the interface between the gold and titanium oxide support, which is considered to be an active site for CO oxidation. The mean inner potential of the gold particles also changed as their size decreased. The value of the inner potential of gold, which is approximately 25 V in bulk state, rose to over 40 V when the size of the gold particles was less than 2 nm. This phenomenon indicates the existence of a charge transfer at the interface between gold and titanium oxide. The 3-D structure change and the inner potential change should be attributed to the specific electronic structure at the interface, owing to both the “nano size effect” and the “hetero-interface effect.”

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From 0-dimension to 1-dimensions: Au nanocrystals as versatile plasmonic photocatalyst for broadband light induced RAFT polymerization

Polymer Chemistry ◽

10.1039/d1py00088h ◽

2021 ◽

Vol 12 (16) ◽

pp. 2439-2446

Author(s):

Junle Zhang ◽

Mengya Li ◽

Yanjie He ◽

Xiaomeng Zhang ◽

Zhe Cui ◽

...

Keyword(s):

Gold Nanoparticles ◽

Raft Polymerization ◽

Plasmonic Photocatalyst

Gold nanoparticles and nanorods were utilized as the catalyst for photo-induced RAFT polymerization, because of their strong LSPR performance.

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Two Approaches to the Laser-Induced Formation of Au/Ag Bimetallic Nanoparticles in Supercritical Carbon Dioxide

Nanomaterials ◽

10.3390/nano11061553 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1553

Author(s):

Alexey Rybaltovsky ◽

Evgeniy Epifanov ◽

Dmitriy Khmelenin ◽

Andrey Shubny ◽

Yuriy Zavorotny ◽

...

Keyword(s):

Carbon Dioxide ◽

Supercritical Carbon Dioxide ◽

Ag Nanoparticles ◽

Repetition Rate ◽

Pulse Repetition Rate ◽

Bimetallic Nanoparticles ◽

Side Wall ◽

Pulse Repetition ◽

Gold Core ◽

Supercritical Carbon

Two approaches are proposed for the synthesis of bimetallic Au/Ag nanoparticles, using the pulsed laser ablation of a target consisting of gold and silver plates in a medium of supercritical carbon dioxide. The differences between the two approaches related to the field of “green chemistry” are in the use of different geometric configurations and different laser sources when carrying out the experiments. In the first configuration, the Ag and Au targets are placed side-by-side vertically on the side wall of a high-pressure reactor and the ablation of the target plates occurs alternately with a stationary “wide” horizontal beam with a laser pulse repetition rate of 50 Hz. In the second configuration, the targets are placed horizontally at the bottom of a reactor and the ablation of their parts is carried out by scanning from above with a vertical “narrow” laser beam with a pulse repetition rate of 60 kHz. The possibility of obtaining Ag/Au alloy nanoparticles is demonstrated using the first configuration, while the possibility of obtaining “core–shell” bimetallic Au/Ag nanoparticles with a gold core and a silver shell is demonstrated using the second configuration. A simple model is proposed to explain the obtained results.

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An efficient and robust exfoliated bentonite/Ag3PO4/AgBr plasmonic photocatalyst for degradation of parabens

RSC Advances ◽

10.1039/d0ra02455d ◽

2020 ◽

Vol 10 (27) ◽

pp. 16027-16037 ◽

Cited By ~ 1

Author(s):

Jianchao Ma ◽

Shurong Yang ◽

Huixian Shi ◽

Jin Pang ◽

Xiaopeng Zhang ◽

...

Keyword(s):

Plasmonic Photocatalyst

A mesoporous exfoliated bentonite (EB)/Ag3PO4/AgBr (30%) photocatalyst was designed to combine various functions to achieve efficient photodegradation of parabens.

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Iron Oxide-Gold Core-Shell Nanoparticles as Multimodal Imaging Contrast Agent

IEEE Sensors Journal ◽

10.1109/jsen.2013.2253215 ◽

2013 ◽

Vol 13 (6) ◽

pp. 2341-2347 ◽

Cited By ~ 15

Author(s):

Luca Menichetti ◽

Leonardo Manzoni ◽

Luigi Paduano ◽

A. Flori ◽

Claudia Kusmic ◽

...

Keyword(s):

Iron Oxide ◽

Contrast Agent ◽

Multimodal Imaging ◽

Core Shell ◽

Shell Nanoparticles ◽

Gold Core ◽

Core Shell Nanoparticles ◽

Imaging Contrast Agent

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Utilizing Scanning Transmission Electron Microscopy to Locate and Image Raman Active Gold Core Nanoparticles in Mouse Tissue

Microscopy and Microanalysis ◽

10.1017/s1431927610061556 ◽

2010 ◽

Vol 16 (S2) ◽

pp. 1116-1117

Author(s):

PJ Kempen ◽

AS Thakor ◽

CL Zavaleta ◽

SS Gambhir ◽

R Sinclair

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Scanning Transmission Electron Microscopy ◽

Mouse Tissue ◽

Scanning Transmission Electron ◽

Gold Core ◽

Transmission Electron ◽

Scanning Transmission ◽

Core Nanoparticles

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.

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A semimetal bismuth element as a direct plasmonic photocatalyst

Chemical Communications ◽

10.1039/c4cc02724h ◽

2014 ◽

Vol 50 (72) ◽

pp. 10386-10389 ◽

Cited By ~ 188

Author(s):

Fan Dong ◽

Ting Xiong ◽

Yanjuan Sun ◽

Zaiwang Zhao ◽

Ying Zhou ◽

...

Keyword(s):

Photocatalytic Activity ◽

Surface Plasmon Resonance ◽

Surface Plasmon ◽

Plasmon Resonance ◽

Plasmonic Photocatalyst

A semimetal bismuth element exhibited admirable photocatalytic activity towards the removal of NO in air, and most strikingly, showed a catalytic “memory” capability, resulting from the surface plasmon resonance mediated direct photocatalysis.

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A visible light-driven plasmonic photocatalyst

Light Science & Applications ◽

10.1038/lsa.2014.14 ◽

2014 ◽

Vol 3 (1) ◽

pp. e133-e133 ◽

Cited By ~ 149

Author(s):

Francesca Pincella ◽

Katsuhiro Isozaki ◽

Kazushi Miki

Keyword(s):

Visible Light ◽

Plasmonic Photocatalyst ◽

Visible Light Driven

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Study of a highly porous composite material based on an aluminum matrix with an ordered cellular structure formed by hollow copper-graphite spherical granules

Perspektivnye Materialy ◽

10.30791/1028-978x-2021-11-39-46 ◽

2021 ◽

Vol 11 ◽

pp. 39-46

Author(s):

V. A. Gulevskiy ◽

◽

V. I. Antipov ◽

L. V. Vinogradov ◽

S. N. Tsurikhin ◽

...

Keyword(s):

Composite Material ◽

Cellular Structure ◽

Aluminum Matrix ◽

Expanded Polystyrene ◽

Porous Composite ◽

Porous Composite Material ◽

Cellular Composite ◽

Highly Porous ◽

Spherical Hollow ◽

Copper Shell

The structure and properties of a highly porous cellular composite material based on a framework of hollow spherical granules with a thin copper-graphite coating impregnated with an aluminum alloy have been investigated. Highly porous composite composite casting with molten form, filled with expanded polystyrene spherical granules with a thin copper-graphite layer applied to their surface. When the polymer core of the granules burns out in the casting, a highly porous cellular composite material is formed with an aluminum matrix filled with spherical pores ∅ 4 – 8 mm, adjoining the metal matrices through a thin (300 – 500 μm) copper shell. The density of the porous composite material obtained in this way is 1.67 g/cm3. In order to fill the space between the granules with aluminum melt, their surfaces were coated with a thin layer of titanium, molybdenum, or chromium borides, which positively affected the strength characteristics of the composite material as a whole. Estimated calculation of the shock absorber index of a new highly porous structural material based on aluminum matrices with a cellular structure made of spherical hollow granules regularly distributed over the volume proved the prospects of its subsequent use as an absorber of shock energy in shock-absorbing devices.

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