Date of Award

5-2022

Document Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Chemistry

Committee Chair/Advisor

Dr. Sourav Saha

Committee Member

Dr. Bill Pennington

Committee Member

Dr. Stephen Creager

Committee Member

Dr. Shiou-Jyh Hwu

Abstract

Composed of metal clusters nodes and organic linkers, metal-organic frameworks (MOFs) have emerged as versatile platforms with unparalleled chemical and structural tunability, synthetic facility, permanent porosity, and size-selective guest encapsulation capability. These features make them potential candidates for a variety of applications such as gas storage,drug delivery, catalysis,and sensing. In recent years, the introduction of redox- and photoactive components have yielded stimuli-responsive electronic and photonic MOFs and expanded their utility in molecular electronics and energy storage devices/technologies.

Chapter one describes the light-harvesting ability of a porphyrin-based MOF. Herein, we have demonstrated spontaneous solvothermal growth of [100]-oriented uniform pillared-porphyrin framework-11 (PPF-11) films and incorporated them as photoanodes in solar cells, which displayed greater photovoltaic response and power conversion efficiency (PCE: 0.86%) than control devices (PCE ≤ 0.2%) as well as other intrinsically light-harvesting 3D MOFs reported to date.

Chapter 2 depicts that although MOFs share structural similarities with crystalline inorganic semiconductors, electrical conductivity remains one of the most challenging but desirable features, which requires high charge-carrier concentration as well as efficient charge transport capability. Examples of conductivity enhancement upon guest-induced framework oxidation or reduction, π-donor/acceptor stack formation, crosslinking of coordinatively unsaturated nodes, among others are discussed.

Chapters 3,4 and 5 present the synthesis, structural characterization, optical, and electronic properties of several new electrically conducting 2D and 3D MOFs based on electron-rich tetrathiafulvalene derivatives. Their guest-induced conductivity enhancement via ligand oxidation is reported in these chapters.

Finally, Chapter 6 describes the preparation of a new conducting MOF-polymer-Au nanoparticle (AuNP) hybrid material based on NU-1000 MOF platform. A redox-active polymer polydopamine (PDA) containing electron-rich/reducing functional groups was introduced inside the MOF channels via in-situ polymerization of dopamine monomers, which reduced Au3+ into metallic gold, creating Au-NPs. The new triple-composite displayed a conductivity ~104 times higher than that of the pristine MOF and the NU-1000/PDA composite.

Available for download on Wednesday, April 12, 2023

Share

COinS