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plasmon-effects
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Influence of Au thickness on the performance of plasmonic enhanced hematite photoanodes
, Article RSC Advances ; Volume 3, Issue 39 , 2013 , Pages 17837-17842 ; 20462069 (ISSN) ; Kikhavani, M. R ; Sheshyekani, K ; Dabirian, A ; Sharif University of Technology
2013
Abstract
The surface plasmon effect of Au nanostructures placed on the surface of hematite has recently been used to enhance light absorption within its carrier collection distance of 10 nm from the water-hematite interface. Despite significant narrow band absorption enhancements in the visible region, the reported enhancements in the overall performance of the cell under standard AM1.5 sunlight illumination are not significant. We numerically design an array of Au stripes on the surface of an extremely thin layer of hematite to maximize the number of charge carriers that can reach the hematite-water interface and explore the optical processes involved. The lateral dimensions and in particular the...
High-performance UV‐Vis-NIR photodetectors based on plasmonic effect in Au nanoparticles/ZnO nanofibers
, Article Applied Surface Science ; Volume 483 , 2019 , Pages 1110-1117 ; 01694332 (ISSN) ; Arab Bafrani, H ; Naseri, A ; Moshfegh, A. Z ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In this study, UV‐Vis-NIR photodetectors based on decorated ZnO nanofibers (NFs) with optimized coverage of Au nanoparticles (NPs) fabricated via combined simple electrospinning and sputtering techniques are introduced. The effect of different coverages of Au NPs resulted from different Au nominal layer thicknesses on the morphology and optical properties of the ZnO fibers are investigated through various characterization methods. It is discovered that 4 nm Au nominal thickness provides the highest UV on/off ratio (~460), responsivity (~332 A/W), detectivity (~2.93×10 11 Jones) as well as faster rise and decay times as compared to pure ZnO nanofibers. A broad spectral response from UV to NIR...
Synthesis & Characterization of Au-HKUST-1 Nanocomposite and Evaluation of Plasmonic Properties of Gold Nanoparticles in this Nanocomposite
, M.Sc. Thesis Sharif University of Technology ; Madaah Hosseini, Hamid Reza (Supervisor)
Abstract
In the past few years, many research works on the controllable integration of metal nanoparticles and metal-organic frameworks were done, since the obtained composite material shows a synergism effect in catalysis and photocatalysis, drug delivery applications, gas, and energy storage, as well as sensing. For the first time, in this study, we employed template-assisted growth to synthesize Au-HKUST-1 Nanocomposite. XRD analysis entirely confirms that employing this strategy in synthesizing Au-HKUST-1 was wholly successful, and the plasmonic properties of this nanostructure were studied via UV-visible spectroscopy. In the course of synthesis, gold nanoparticles with 70nm diameter were...
Synthesis of magneto-plasmonic Au-Ag NPs-decorated TiO2-modified Fe3O4 nanocomposite with enhanced laser/solar-driven photocatalytic activity for degradation of dye pollutant in textile wastewater
, Article Ceramics International ; Volume 45, Issue 14 , 2019 , Pages 17837-17846 ; 02728842 (ISSN) ; Anvari, A ; Sadighi Bonabi, R ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
The synergistic effect of plasmonic Au-Ag nanoparticles (NPs) on the increase of absorption band of nano-sized TiO2 and magnetic property of Fe3O4 NPs on the separation-ability of this semiconductor was applied for preparation of eight magneto-plasmonic photocatalysts for degradation of rhodamine-6G (Rh6G) in textile wastewater. The size, structure, morphology, crystallinity and optical and magnetic properties of prepared photocatalysts have been evaluated by various characterization techniques. Their photocatalytic activities were assessed under irradiation of an intense linear 405-nm laser and a continuous solar-simulated xenon lamp. The results were demonstrated that in comparison to the...
Investigation of the Hybrid Structures based on Carbon Materials for Solar Steam Generation
, Ph.D. Dissertation Sharif University of Technology ; Irajizad, Azam (Supervisor) ; Esfandiar, Ali (Supervisor)
Abstract
Two-dimensional nanostructures can significantly absorb solar irradiation, due to diverse energy levels, large effective surfaces, layered and porous structures with adjustable physical and chemical properties. Mono and multilayers of graphene, as the first isolated 2D materials with special band-structure of a zero-band gap, along with impressive optical properties, tunable light interaction, and adjustable optical properties by chemical doping or structural defects, have great potential for the next generation of nanophotonic devices. So, graphene is an appropriate candidate for absorption, frequent reflection, and energy conversion of electromagnetic waves at the frequency range of the...
Multiway investigation of interaction between fluorescence labeled DNA strands and unmodified gold nanoparticles
, Article Analytical Chemistry ; Volume 84, Issue 15 , July , 2012 , Pages 6603-6610 ; 00032700 (ISSN) ; Kompany Zareh, M ; Hormozi Nezhad, M. R ; Sharif University of Technology
ACS
2012
Abstract
The single stranded DNA can be adsorbed on the negatively charged surface of gold nanoparticles (AuNPs), but the rigid structure of double stranded DNA prevents it from adsorption. Signal of a tagged single stranded DNA will be quenched by the plasmon effect of the AuNP surface after its adsorption. This phenomenon has been used to study the DNA hybridization and interactions of two complementary 21mer oligonucleotides each tagged with a different fluorescent dye in the presence of 13 nm gold nanoparticles. The DNA strands used in this study belong to the genome of HIV. The obtained rank deficient three-way fluorescence data sets were resolved by both PARAFAC and restricted Tucker3 models....
Plasmonic effects of infiltrated silver nanoparticles inside TiO2 film: Enhanced photovoltaic performance in DSSCs
, Article Journal of the American Ceramic Society ; Volume 99, Issue 1 , 2016 , Pages 167-173 ; 00027820 (ISSN) ; Mohammadi, M. R ; Sharif University of Technology
Blackwell Publishing Inc
Abstract
The plasmonic effects of infiltrated silver (Ag) nanoparticles, with different contents, inside a nanostructured TiO2 film on the photovoltaic performance of dye-sensitized solar cells (DSSCs) are explored. The synthesized Ag nanoparticles are immobilized onto deposited TiO2 nanoparticles by a new strategy using 3-mercaptopropionic acid (MPA), a bifunctional linker molecule. Transmission electron microscope (TEM) images show that monodispersed Ag and polydispersed TiO2 nanoparticles have an average diameter of 12 ± 3 nm and 5 ± 1 nm, respectively. Moreover, Fourier transform infrared spectroscopy (FTIR) analysis reveals that Ag nanoparticles were successfully functionalized and capped with...