Search results

(1 - 2 of 2)
ENGINEERING 2D PHOTO-REACTING COF FOR PATTERNING AND DRUG DELIVERY
Title
ENGINEERING 2D PHOTO-REACTING COF FOR PATTERNING AND DRUG DELIVERY
Creator
Chen, Kuo Hao
Date
2017, 2017-07
Description
Covalent Organic Frameworks (COFs) are 2-dimensional polymers that exhibit rigid and large surface area as well as porous architectures....
Show moreCovalent Organic Frameworks (COFs) are 2-dimensional polymers that exhibit rigid and large surface area as well as porous architectures. Currently, COFs are tailored for gas storage applications, drug delivery, catalysis and they are used as filtering membranes for water treatment. It is well documented that at the nano/micro scale, COFs can form multi-layered architecture with respect to the basic molecular building blocks. In this picture, it is possible that the 2D intra-layer and 3D inter-layer interactions of the basic molecular units COFs may dictate the overall efficiency of the aforementioned applications. To understand the dimensionality-function relationship of COFs, we are engineering hybrid 1D-2D organic polymers. This hybrid architecture will allow us to study the propagation of energy/exciton transfer within the resulting materials among other applications such as drug delivery and light-induced nano/micro-patterning. To achieve our objectives, I exploited the photo-reacting properties of two molecular systems: The first system is used to prepare the 2D COF of interest and the other system is used to engineer a 1D crystalline solid. Although I have not tested the energy/exciton propagation with the desired material, I have successfully engineered a 1D crystalline solid and synthesized the expected 2D COFs. Using a combination of synthetic strategies, I prepared and characterized photoreacting tetra-phenyl ketone building block that was used to form the desired polymer. I have also engineered 1D needle-like crystals of bisphenyl cyclopropenone compound. Moreover, the two materials were characterized by optical and electron microscopy methods. This thesis will detail the synthesis and characterization of all precursors of the basic molecular units that were used to engineer the 1D crystalline solid and 2D COF materials. Condignly, the optical and scanning electron microscopy images highlight the microscale features of the materials of interest. I am certain that this preliminary investigation will pave the way to study the dimensionality of energy/exciton transfer and reaction propagation in the many organic materials.
M.S. in Chemistry, July 2017
Show less
Photochemical Reaction of Covalent Organic Frameworks: Probing the Changes in Surface Area and Topology of the Frameworks
Title
Photochemical Reaction of Covalent Organic Frameworks: Probing the Changes in Surface Area and Topology of the Frameworks
Creator
Ye, Yuxin
Date
2019
Description
Covalent organic frameworks (COFs) are a new class of 2-dimensional or 3-dimensional polymers that have rigid and porous structures. COFs are...
Show moreCovalent organic frameworks (COFs) are a new class of 2-dimensional or 3-dimensional polymers that have rigid and porous structures. COFs are widely applied in gas storage, catalysts, photo conductivity, and drug delivery. Since the applications of COFs are highly related to their structures, it is necessary to learn the stability of COFs under certain conditions. In this research, the stability of COFs towards light was mainly focused on. A new tetraphenyl substituted ketone based COF was synthesized and characterized with Fourier transform infrared spectroscopy, scanning electron microscopy, differential scanning calorimetry, ultraviolet-visible spectroscopy, and powder X-ray diffraction. Infrared spectra proved that this new COF can undergo Norrish type I reaction to release carbon monoxide under UV irradiation, while main structure of this COF was not broken. This thesis will detailly discussed the synthesis and characterization of this new COF, as well as the building blocks, linkers, and other precursors. This thesis will give some inspirations in the study of energy transfer in covalent organic frameworks.
Show less