Investigation of carboxyl-functionalized self-assembled monolayers on gold surfaces.

Download

index.pdf

Date

2020

Author

Görgülü, Salih

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

201
views

92
downloads

Thiolated derivatives of dicarba-closo-dodecaborane, HS-C 2 B 10 H 11 (carboranethiol, CT), with icosahedral molecular structure are one of the promising candidates for self-assembled monolayer (SAM) applications. CT SAMs possess various advantages relative to their organic counterparts, such as high stability towards chemical, oxidative and thermal degradations as well as having fewer defects. In this study unfunctionalized CT SAMs (M1, M9) and carboxylic group functionalized CT SAMs (M1C, M9C) as well as their corresponding mixed SAMs were investigated on template stripped gold surfaces. Wetting properties of the SAMs were studied by using contact angle (CA) measurements. The ellipsometric thickness of all SAMs were found to be about 1-2 nm which is consistent with the reported thickness, measured by scanning tunneling microscopy (STM), in the literature. In mixed SAMs, surface fraction of M1 was found to be higher than its solution fraction in the M1:M1C and M1:M9C mixtures indicating the dominant component on the surface to be M1. Similar behavior was also observed for M9 such that surface fraction of M9 was higher than its solution fraction in the M9:M1C and M9:M9C mixtures indicating the dominancy of M9 molecules on the surface. M1 and M9 molecules bind to gold surface stronger than M1C and M9C molecules. In replacement experiments of CT SAMs, M1 molecules were found to replace M9C faster than M9C replaces M1 on template stripped gold surface. Replacement experiments of CT SAMs on silver surface were also performed. It was found that M9C molecules bind to silver surfaces through carboxylic groups rather than the thiol group.

Subject Keywords

Self-assembly (Chemistry)., Keywords: Carboranethiol, Self-Assembled monolayers, Gold surfaces, Contact angle.

URI

http://etd.lib.metu.edu.tr/upload/12625240/index.pdf
https://hdl.handle.net/11511/45327

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

A theoretical study on certain iron-sulfur and iron-selenium clusters Turker, L; Erkoç, Şakir (Elsevier BV, 2003-04-04) [Fe4S4], [Fe4S3Se] and [Fe4Se4] type iron-sulfur and iron-sulfur-selenium and iron-selenium clusters, all having four cysteinyl moieties as ligands have been considered for ab initio quantum chemical analysis at the level of 6-31G (RHF). All the structures are found to be stable and the stability of Se containing structures increases as the number of Se atoms increases. The inter frontier molecular orbital energy gaps and the HOMO energies follow the same order.
Mixed carboranethiol self-assembled monolayers on gold surfaces Sohrabnia, Nima; Danışman, Mehmet Fatih; Yılmaz, Ayşen; Department of Chemistry (2017) Thiolated derivatives of dicarba-closo-dodecaborane, HS-C2B10H11 (carboranethiols, CTs), with icosahedral molecular structure are one of the promising candidates for self-assembled monolayer (SAM) applications. CT SAMs possess various advantages relative to organic counterparts, such as high stability towards chemical, oxidative and thermal degradations as well as having fewer defects. In this study, pure and mixed SAMs of three different positional isomers of carboranethiols (namely M1, O1 and M9) on templ...
Novel Molecular Building Blocks Based on the Boradiazaindacene Chromophore: Applications in Fluorescent Metallosupramolecular Coordination Polymers Bozdemir, Oe. Altan; Buyukcakir, Onur; AKKAYA, Engin Umut (Wiley, 2009-01-01) We designed and synthesized novel boradiazaindacene (Bodipy) derivatives that are appropriately functionalized for metal-ion-mediated supramolecular polymerization. Thus, ligands for 2-terpyridyl-, 2,6-terpyridyl-. and bipyridyl-functionalized Bodipy dyes were synthesized through Sonogashira couplings. These fluorescent building blocks are responsive to metal ions in a stoichiometry-dependent manner. Octahedral coordinating metal ions such as Zn-II result in polymerization at a stoichiometry corresponding t...
Theoretical investigation of hydroxytyrosol and its radicals Erkoc, F; Keskin, N; Erkoç, Şakir (Elsevier BV, 2003-05-05) The structural and electronic properties of hydroxytyrosol, its three radical isomers, and its three analogues hydroxytyrosol-dihydroxyl isomers have been investigated theoretically by performing semi-empirical self-consistent field molecular orbital theory calculations. The geometry of the systems have been optimized and the electronic properties have been calculated at the level of AMI method.
Synthesis and Characterization of Thiophene and Thieno[3,2-b]thiophene Containing Conjugated Polymers Rustamh, Elvin; Goker, Seza; UDUM, YASEMİN; Udum, Yasemin Arslan; Toppare, Levent Kamil (The Electrochemical Society, 2015-01-01) Herein, we report the synthesis of two donor-acceptor-donor polymers (P1 and P2) based on thiophene (M1) and thieno [3,2-b]thiophene (M2) as the donor and 2,5-bis(dodecyloxy)benzene as the acceptor unit. The effects of different donor units on the polymers' electrochemical and optical properties were examined by cyclic voltammetry and spectroelectrochemical analysis. Introducing thieno[3,2-b]thiophene unit as the donor unit enhances pi-stacking and consequently lowering the bandgap of the resulting polymer....

Citation Formats

S. Görgülü, “Investigation of carboxyl-functionalized self-assembled monolayers on gold surfaces.,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Chemistry., Middle East Technical University, 2020.