scholarly journals Plasmonic enhancement of the antibacterial photodynamic efficiency of a zinc tetraphenylporphyrin photosensitizer/dextran graft polyacrylamide anionic copolymer/Au nanoparticles hybrid nanosystem

RSC Advances ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 11-23
Author(s):  
Oleg A. Yeshchenko ◽  
Nataliya V. Kutsevol ◽  
Anastasiya V. Tomchuk ◽  
Pavlo S. Khort ◽  
Pavlo A. Virych ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Au Nanoparticles ◽  
Plasmonic Enhancement ◽  
Au Nps ◽  
Hybrid Nanosystem

A zinc tetraphenylporphyrin photosensitizer/dextran graft polyacrylamide anionic copolymer/Au nanoparticles (ZnTPP/D-g-PAAan/Au NPs) triple hybrid nanosystem has been proposed as a nanodrug for potential photodynamic therapy applications.

scholarly journals Fabrication and Application of SERS-Active Cellulose Fibers Regenerated from Waste Resource

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2142
Author(s):  
Shengjun Wang ◽  
Jiaqi Guo ◽  
Yibo Ma ◽  
Alan X. Wang ◽  
Xianming Kong ◽  
...  
Keyword(s):  
Au Nanoparticles ◽  
Cellulose Fiber ◽  
Cellulose Fibers ◽  
Regenerated Cellulose ◽  
Sers Substrate ◽  
Au Nps ◽  
Convenient Approach ◽  
Theoretical Simulations ◽  
Difference Time ◽  
Raman Probe

The flexible SERS substrate were prepared base on regenerated cellulose fibers, in which the Au nanoparticles were controllably assembled on fiber through electrostatic interaction. The cellulose fiber was regenerated from waste paper through the dry-jet wet spinning method, an eco-friendly and convenient approach by using ionic liquid. The Au NPs could be controllably distributed on the surface of fiber by adjusting the conditions during the process of assembling. Finite-difference time-domain theoretical simulations verified the intense local electromagnetic fields of plasmonic composites. The flexible SERS fibers show excellent SERS sensitivity and adsorption capability. A typical Raman probe molecule, 4-Mercaptobenzoicacid (4-MBA), was used to verify the SERS cellulose fibers, the sensitivity could achieve to 10−9 M. The flexible SERS fibers were successfully used for identifying dimetridazole (DMZ) from aqueous solution. Furthermore, the flexible SERS fibers were used for detecting DMZ from the surface of fish by simply swabbing process. It is clear that the fabricated plasmonic composite can be applied for the identifying toxins and chemicals.

A novel photoelectrode based on eosin Y–rhodamine B duo-dye sensitized Au nanoparticles by in situ reduction

2017 ◽  
Vol 9 (38) ◽  
pp. 5586-5592 ◽  
Author(s):  
Y. L. Yuan ◽  
G. M. Pang ◽  
X. K. Li ◽  
W. Y. Zhu ◽  
H. C. Pan
Keyword(s):  
Rhodamine B ◽  
Au Nanoparticles ◽  
Specific Response ◽  
Eosin Y ◽  
In Situ Reduction ◽  
Au Nps ◽  
Dye Sensitized ◽  
Novel Strategy

A novel strategy for the fabrication of a photoelectrochemical system, involving a duo-dye sensitized Au NPs composite, that displays a specific response to mercury.

Sensitive Hg2+ Ion Detection Using Metal Enhanced Fluorescence of Novel Polyvinyl Pyrrolidone (PVP)-Templated Gold Nanoparticles

2018 ◽  
Vol 72 (11) ◽  
pp. 1645-1652 ◽  
Author(s):  
Kailong Dong ◽  
Jiasheng Zhou ◽  
Taiqun Yang ◽  
Shan Dai ◽  
Hao Tan ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Detection Limit ◽  
Au Nanoparticles ◽  
Polyvinyl Pyrrolidone ◽  
Quenching Mechanism ◽  
Ion Detection ◽  
Enhanced Fluorescence ◽  
Metal Enhanced Fluorescence ◽  
One Pot ◽  
Au Nps

In this study, we report a straightforward strategy for Hg2+ ion detection. Fluorescent Au nanoparticles (NPs) were one-pot synthesized using a polymer (polyvinyl pyrrolidone [PVP]) as both capping and fluorescence agent. The as-synthesized PVP-Au NPs showed a remarkably rapid response selectively for Hg2+ ions compared to 14 other metal ions. The detection limit of Hg2+ was estimated at 100 nM. We discuss the emission and quenching mechanism of the PVP-Au NPs, the former being attributed to metal enhanced fluorescence and the latter being related to static quenching by Hg2+. The fluorescence of PVP-Au NPs offers an efficient and reliable strategy for Hg2+ ions detection. They therefore have a great potential for applications in health and environmental monitoring.

scholarly journals CO Total and Preferential Oxidation over Stable Au/TiO2 Catalysts Derived from Preformed Au Nanoparticles

Catalysts ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1028
Author(s):  
Núria J. Divins ◽  
Eduardo López ◽  
Inmaculada Angurell ◽  
Stefan Neuberg ◽  
Ralf Zapf ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Au Nanoparticles ◽  
Gold Catalyst ◽  
Space Velocity ◽  
Ex Situ ◽  
Oxidation Reactions ◽  
Preferential Oxidation ◽  
Au Nps ◽  
Tio2 Anatase ◽  
Operation Conditions

CO preferential oxidation (PROX) is an effective method to clean reformate H2 streams to feed low-temperature fuel cells. In this work, the PROX and CO oxidation reactions were studied on preformed Au nanoparticles (NPs) supported on TiO2 anatase. Preformed Au NPs were obtained from gold cores stabilized by dodecanethiols or trimethylsilane-dendrons. A well-controlled size of ca. 2.6 nm and narrow size distributions were achieved by this procedure. The catalysts were characterized by high-resolution transmission electron microscopy and ex situ and in situ X-ray photoelectron spectroscopy (XPS). The XPS results showed that the preformed Au NPs exhibited high thermal stability. The different ligand-derived Au catalysts, as well as a conventional gold catalyst for comparison purposes, were loaded onto cordierite supports with 400 cells per square inch. The activity and selectivity of the samples were evaluated for various operation conditions. The catalyst prepared using dodecanethiol-capped Au NPs showed the best performance. In fact, CO conversions of up to 70% at 40% CO2 selectivity and 90% O2 conversion were observed operating at 363 K in H2-rich atmospheres. The performance of the best catalysts was subsequently tested on stainless steel microreactors. A 500-hour stability test was carried out under a real post-reformate stream, including 18 vol.% CO2 and 29 vol.% H2O. A mean CO conversion of ca. 24% was measured for the whole test operating at 453 K and a gas hourly space velocity (GHSV) of 1.3 × 104 h−1. These results reveal our dodecanethiol- and carbosilane-derived Au catalysts as extremely promising candidates to conduct a PROX reaction while avoiding deactivation, which is one of the major drawbacks of Au/TiO2 catalysts.

Construction of a multi-interfacial-electron transfer scheme for efficient CO2 photoreduction: a case study using CdIn2S4 micro-flower spheres modified with Au nanoparticles and reduced graphene oxide

2020 ◽  
Vol 8 (36) ◽  
pp. 18707-18714 ◽  
Author(s):  
Xin Li ◽  
Haopeng Jiang ◽  
Changchang Ma ◽  
Zhi Zhu ◽  
Xianghai Song ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Au Nanoparticles ◽  
Interfacial Electron Transfer ◽  
Transfer Scheme ◽  
Au Nps ◽  
Co2 Photoreduction ◽  
Reduced Graphene

CdIn2S4 micro-flower spheres modified with Au NPs and rGO have been designed for CO2 photoreduction.

Ultrafine Au nanoparticles anchored on Bi2MoO6 with abundant surface oxygen vacancies for efficient oxygen molecule activation

2019 ◽  
Vol 9 (12) ◽  
pp. 3193-3202 ◽  
Author(s):  
Li Guo ◽  
Qiang Zhao ◽  
Huidong Shen ◽  
Xuanxuan Han ◽  
Kailai Zhang ◽  
...  
Keyword(s):  
Photocatalytic Degradation ◽  
Oxygen Vacancies ◽  
Au Nanoparticles ◽  
Oxygen Molecule ◽  
Surface Oxygen ◽  
Au Nps

Au NPs were anchored on Bi2MoO6 with rich SOVs to improve O2 activation for photocatalytic degradation of phenol and dye.

scholarly journals Controlled positioning of nanoparticles on a micrometer scale

2012 ◽  
Vol 3 ◽  
pp. 773-777 ◽  
Author(s):  
Fabian Enderle ◽  
Oliver Dubbers ◽  
Alfred Plettl ◽  
Paul Ziemann
Keyword(s):  
Electron Beam ◽  
Electron Beam Lithography ◽  
Au Nanoparticles ◽  
Self Organization ◽  
Top Down ◽  
Ion Etching ◽  
Au Nps ◽  
Si Substrates ◽  
Square Array ◽  
Micrometer Scale

For many applications it is desirable to have nanoparticles positioned on top of a given substrate well separated from each other and arranged in arrays of a certain geometry. For this purpose, a method is introduced combining the bottom-up self-organization of precursor-loaded micelles providing Au nanoparticles (NPs), with top-down electron-beam lithography. As an example, 13 nm Au NPs are arranged in a square array with interparticle distances >1 µm on top of Si substrates. By using these NPs as masks for a subsequent reactive ion etching, the square pattern is transferred into Si as a corresponding array of nanopillars.

scholarly journals The effect of heat treatment on the morphology and mobility of Au nanoparticles

2020 ◽  
Vol 11 ◽  
pp. 61-67
Author(s):  
Sven Oras ◽  
Sergei Vlassov ◽  
Simon Vigonski ◽  
Boris Polyakov ◽  
Mikk Antsov ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Au Nanoparticles ◽  
Annealing Temperature ◽  
Kinetic Monte Carlo ◽  
Si Substrate ◽  
Au Nps ◽  
Silica Substrate ◽  
Atomic Force ◽  
Kinetic Monte Carlo Simulations ◽  
Higher Temperature

In the present paper, we investigate the effect of heat treatment on the geometry and mobility of Au nanoparticles (NPs) on a Si substrate. Chemically synthesized Au NPs of diameter ranging from 5 to 27 nm were annealed at 200, 400, 600 and 800 °C for 1 h. A change in the geometry from faceted to more rounded shapes were observed with increasing annealing temperature. Kinetic Monte Carlo simulations indicate that the NPs become rounded due to the minimization of the surface area and the transition to lower energy surface types {111} and {100}. The NPs were manipulated on a silica substrate with an atomic force microscope (AFM) in tapping mode. Initially, the NPs were immovable by AFM energy dissipation. However, annealed NPs became movable, and less energy was required to displace the NPs annealed at higher temperature. However, after annealing at 800 °C, the particles became immovable again. This effect was attributed to the diffusion of Au into the Si substrate and to the growth of the SiO2 layer.

scholarly journals A rapid and ultrasensitive colorimetric biosensor based on aptamer functionalized Au nanoparticles for detection of saxitoxin

RSC Advances ◽  
2020 ◽  
Vol 10 (26) ◽  
pp. 15293-15298
Author(s):  
Le Qiang ◽  
Yu Zhang ◽  
Xin Guo ◽  
Yakun Gao ◽  
Yingkuan Han ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Au Nanoparticles ◽  
Colorimetric Sensor ◽  
Quantitative Detection ◽  
Au Nps

We demonstrate a facile and ultrasensitive colorimetric sensor based on gold nanoparticles (Au NPs) and aptamer (Au NPs-aptamer biosensor) for specific and quantitative detection of STX.

scholarly journals Enhanced Photocatalytic Performance and Mechanism of Au@CaTiO3 Composites with Au Nanoparticles Assembled on CaTiO3 Nanocuboids

Micromachines ◽  
2019 ◽  
Vol 10 (4) ◽  
pp. 254 ◽  
Author(s):  
Yuxiang Yan ◽  
Hua Yang ◽  
Zao Yi ◽  
Ruishan Li ◽  
Xiangxian Wang
Keyword(s):  
Photoelectron Spectroscopy ◽  
Photocatalytic Performance ◽  
Au Nanoparticles ◽  
Diffuse Reflectance Spectroscopy ◽  
Localized Surface Plasmon ◽  
Hydrothermal Route ◽  
Electron Hole ◽  
Photoexcited Electron ◽  
Au Nps ◽  
X Ray

Using P25 as the titanium source and based on a hydrothermal route, we have synthesized CaTiO3 nanocuboids (NCs) with the width of 0.3–0.5 μm and length of 0.8–1.1 μm, and systematically investigated their growth process. Au nanoparticles (NPs) of 3–7 nm in size were assembled on the surface of CaTiO3 NCs via a photocatalytic reduction method to achieve excellent Au@CaTiO3 composite photocatalysts. Various techniques were used to characterize the as-prepared samples, including X-ray powder diffraction (XRD), scanning/transmission electron microscopy (SEM/TEM), diffuse reflectance spectroscopy (UV-vis DRS), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). Rhodamine B (RhB) in aqueous solution was chosen as the model pollutant to assess the photocatalytic performance of the samples separately under simulated-sunlight, ultraviolet (UV) and visible-light irradiation. Under irradiation of all kinds of light sources, the Au@CaTiO3 composites, particularly the 4.3%Au@CaTiO3 composite, exhibit greatly enhanced photocatalytic performance when compared with bare CaTiO3 NCs. The main roles of Au NPs in the enhanced photocatalytic mechanism of the Au@CaTiO3 composites manifest in the following aspects: (1) Au NPs act as excellent electron sinks to capture the photoexcited electrons in CaTiO3, thus leading to an efficient separation of photoexcited electron/hole pairs in CaTiO3; (2) the electromagnetic field caused by localized surface plasmon resonance (LSPR) of Au NPs could facilitate the generation and separation of electron/hole pairs in CaTiO3; and (3) the LSPR-induced electrons in Au NPs could take part in the photocatalytic reactions.

Sign in / Sign up

Export Citation Format

Share Document