Synthesis, functionalization and characterization of gold nanoparticles

Download

index.pdf

Date

2012

Author

Sholanbayeva, Zhanar

Metadata

Show full item record

Item Usage Stats

308
views

118
downloads

Metallic nanoparticles (NPs) with various elemental composition, size, shape and physical or chemical properties has become active field of research. Among all the metal NPs noble metal ones are receiving much attention due to their special optical properties which make them useful for different applications. Noble metal NPs have bright colors resulting from strong surface plasmon resonance absorption usually in the visible region. The colors are size and shape dependent and provide the tuning of optical properties. The optical properties of NPs are also strongly depending on the nature of the NPs surface which plays a crucial role on chemical sensing. Therefore, surface modification of NPs has become increasingly important. In this study, gold NPs were prepared in aqueous phase by seed-mediated growth method. To enhance the optical properties, surface functionalization was performed by coating NPs with silver. The coating process was achieved by chemical reduction of silver ions on NPs surface. Thickness of silver layer on the NPs were attempted to be controlled by the amount of silver salt added into NPs solution. Coating process of different types of gold NPs (rod, octahedral, star) was done by the same procedure. Moreover, this attempt yielded control over silver layer thickness on sphere, rod and octahedral shaped gold NPs, but not on branched NPs. The structure, composition and spectroscopic properties of Au-Ag core shell NPs were characterized by UV-Vis spectroscopy, Field Emission Transmission Electron Microscope (FE-TEM) and Energy-dispersive X-ray (EDX) studies, Scanning Electron Microscope (SEM), and X-Ray Photoelectron Spectroscopy (XPS). The analysis showed that all NPs studied were successfully coated with silver and promising for further explorations in sensing and imaging applications.

Subject Keywords

Nanoparticles., Gold., Nanowires., Nanostructured materials., Electron microscopy., Photoelectron spectroscopy.

URI

http://etd.lib.metu.edu.tr/upload/12615069/index.pdf
https://hdl.handle.net/11511/21943

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Synthesis of gold nanowires with high aspect ratio and morphological purity Dertli, Elçin; Nalbant Esentürk, Emren; Ünalan, Hüsnü Emrah; Department of Micro and Nanotechnology (2012) Metal nanoparticles have unique optical, electrical, catalytic and mechanical properties, which lead them to various applications in nanotechnology. In particular, noble metal nanowires are attracting growing attention due to their potential applications such as in opto-electronic devices and transparent conductive contacts (TCCs). There are two general approaches to synthesize nanowires: template-assisted and solution phase methods. However, these synthesis approaches have various disadvantages. For exampl...
Synthesis, structural and magnetic characterization of soft magnetic nanocrystalline ternary FeNiCo particles Toparlı, Çiğdem; Gürmen, Sebahattin (2017-02-01) The present study focuses on the synthesis, microstructural and magnetic properties of ternary FeNiCo nanoparticles. Nanocrystalline ternary FeNiCo particles were synthesized via hydrogen reduction assisted ultrasonic spray pyrolysis method in single step. The effect of precursor concentration on the morphology and the size of particles was investigated. The syntheses were performed at 800 degrees C. Structure, morphology and magnetic properties of the as-prepared products were characterized through X-ray d...
Preparation and surface modification of noble metal nanoparticles with tunable optical properties for SERS applications Kaya, Murat; Volkan, Mürvet; Department of Chemistry (2011) Metal nanostructures exhibit a wide variety of interesting physical and chemical properties, which can be tailored by altering their size, morphology, composition, and environment. Gold and silver nanostructures have received considerable attention for many decades because of their widespread use in applications such as catalysis, photonics, electronics, optoelectronics, information storage, chemical and biological sensing, surface plasmon resonance and surface-enhanced Raman scattering (SERS) detection. Th...
Modeling of spherulite microstructures in semicrystalline polymers Oktay, H. Emre; Gürses, Ercan (2015-11-01) Semicrystalline polymers are composed of crystalline structures together with amorphous polymer chain networks and therefore they exhibit deformation mechanisms of both crystalline materials and amorphous polymers. One of the most common microstructures observed in semicrystalline polymers is the spherulite microstructure in which crystalline lamellae are embedded in a matrix of amorphous material and grow out from a common central nucleus in radial directions. The mechanical behavior of semicrystalline pol...
Synthesis, spectroscopic and computational analysis of nickel integrated germanium clusters Öğün, Sinem Esra; Nalbant Esentürk, Emren; Department of Chemistry (2014) Nanomaterials are attracting great deal of attention due to their wide range of applications such as in medicine, catalysis and electronics. The use of clusters either as seeds to synthesize larger molecular clusters or in assembled cluster materials is a promising way to prepare new nanomaterials. In particular, the possibility of clusters serving molecular control to design and tuning their properties to fit a particular application makes them more attractive in the search of new advanced materials. There...

Citation Formats

Z. Sholanbayeva, “Synthesis, functionalization and characterization of gold nanoparticles,” M.S. - Master of Science, Middle East Technical University, 2012.