Physical Sciences and Mathematics Commons^™

Alginate/Cucurbit [7] Uril/Dequalinium–Basedb Supramolecular Carbohydrates: Modulation Of Fret Signal By Temperature Control, Amir Sohail Noor Alam Jan

Chemistry Theses

Herein, we describe the synthesis of a bioactive, inexpensive, and easy-tohandle supramolecular carbohydrate polymer by grafting of cucurbit [7] uril macrocycle (CB7)-encapsulated dequalinium chloride hydrate (DCH) onto alginic acid carbohydrates (ALG) via amide linkage formation and show that light energy transfer based on energy migration can be controlled by altering polymer temperature without changing polymer composition. DCH (donor) and 2-anilinonaphthalene-6- sulfonic acid (acceptor) were used to generate Förster resonance energy transfer (FRET) signals. Stationary and time-resolved photoluminescence spectra of the modified carbohydrate platform revealed that FRET resulted in a color change from violet (~387 nm) to blue (~429 nm), which …

Optical Memory Behavior, Metallophilic Luminescence, And Chemical Sensing Ability Of Inorganic And Organometallic Complexes: Development Of Optoelectronic Materials, Aaron D. Nicholas

Electronic Theses and Dissertations

This dissertation is divided into three sections: (1) optical memory, (2) metallophilic-based luminescence, and (3) chemical sensors. (1) Optical memory behavior of d¹⁰metal Cu(I) thiocyanate salts are investigated to explore their potential use in the development of digital data storage devices. From this study we have discovered a new class of CuSCN(3-BrPy)₂optical memory material which undergo a reduction in emission intensity upon laser irradiation. This loss of emission intensity can be reversed simply by heating the sample to room temperature. The mechanism by which this emission loss occurs has been studied, revealing a migrating Br atom …

Luminescence Antenna Behavior In Lanthanide Complexes And Luminescence Sensing In Group 11 Iodides, Francis Barnes

Electronic Theses and Dissertations

In this thesis luminescent materials are studied. The luminescent materials studied are lanthanide complexes and group 11 iodide sensing abilities. Emission intensity of the lanthanide complexes through direct excitation of the lanthanide ion are relatively weak. To overcome this, three unique organic ligands were utilized to synthesize lanthanide nitrate complexes in which higher emission intensity can be observed via the antenna effect. Increased emission intensity resulted for Eu^III and Tb^III complexes for each ligand except triphenylphosphane oxide (only the Tb^III complex demonstrated increased emission intensity). Latva’s empirical rule allows for the antenna effect to occur, in which …

Rare-Earth-Activated Group Vi D0 Metal Oxides As Thermosensitive Phosphors, Samarage Sameera Perera

Wayne State University Dissertations

ABSTRACT

RARE-EARTH-ACTIVATED GROUP VI d0 METAL OXIDES AS

THERMOSENSITIVE PHOSPHORS

by

SAMARAGE SAMEERA PRASAD PERERA

AUGUST 2019

Advisor: Dr. Federico A. Rabuffetti

Major: Chemistry

Degree: Doctor of Philosophy

Thermosensitive phosphors are solid-state materials that demonstrate distinct dependence of luminescence emission on temperature. These materials enable optical temperature sensing in environments where conventional thermometry is not possible (e.g., gas turbines, combustion engines, surface temperature distributions). However, the design of thermosensitive phosphors that show adequate sensitivity and low thermal quenching in the intermediate temperature range (i.e., 500–1000 K) remains challenging. This challenge can be addressed by understanding how to rationally manipulate the …

Photoluminescent Zirconium Complexes For Visible Light Photoredox Catalysis, Yu Zhang

Graduate Theses, Dissertations, and Problem Reports

Early transition metals like zirconium are attractive candidates for the design of luminescent molecules based on earth-abundant elements. Here, a series of zirconium complexes carrying two pyrrolyl-based ligands have been synthesized and characterized. These complexes are photoluminescent upon excitation with visible light and exhibit remarkably long emission lifetimes of hundreds of μs in solution at room temperature. Computational studies using time-dependent density functional theory (TD-DFT) were conducted to identify the nature of the luminescent excited states as mixed intra-ligand/ligand-to-metal charge-transfer (ILCT/LMCT) states. The electrochemistry studies revealed multiple reversible redox events for each zirconium complex. Furthermore, the excited state of the …