Author ORCID Identifier
Date of Award
Department or Program
Porous organic materials with designable structures, large surface areas, low densities, and unique electronic and optical properties have found widespread applications in adsorption, separation, energy storage, and catalysis. However, the majority of organic porous materials are synthesized as fluffy powders, which poses two fundamental challenges for them. Firstly, they lack a single-crystal structure at the microscopic scale, making it difficult to study the specific pore size, shape, and potential substrate binding sites at the atomic level and further establish the structure-property relationship. Secondly, they lack the general processing method and macroscopic shape design, making it difficult to manufacture suitable components for specific applications in real-world settings. Such deficiencies can also potentially impact the material's mass transfer efficiency and other performance aspects. In this thesis, based on my research on porous organic materials, I propose my thoughts and design to help solve the two challenges mentioned.
Firstly, I discussed why we need single crystals and how to synthesize a single-crystalline covalently connected framework. (1) I present examples of the fundamental study of host-guest and guest-guest interactions of multiple guest molecules within a hydrogen-bonded organic framework (HOF) through single-crystal structure analysis. (2) Using our group's unique method for designing hydrogen-bonded cross-linked organic frameworks (HCOFs), I demonstrate the synthesis of single-crystal ionic HCOF-7 with halogen bonding and anion exchanging active sites, which is utilized for both I2 and I- at high temperatures.
Second, I introduce 3D-printing technology to fabricate porous organic materials with macroscopic structures. (1) For the first time, I describe a general method for large-scale synthesis of 3D-printable imine-based covalent organic frameworks (COFs) using the hierarchical self-assembly enabled template synthesis. (2) I discovered that the template synthesis-based 3D printing technique could also be employed for the fabrication of covalently cross-linked amorphous porous polymers with nano-tubular cavities, which could be used for highly efficient natural product separation.
Overall, by integrating knowledge from different fields, I aim to help connect the micro to the macro and establish bridges between the molecular design, materials properties, and real-life application of porous organic materials.
Zhang, Mingshi, "Development of Single-Crystalline and 3D-Printable Porous Organic Materials" (2023). Dartmouth College Ph.D Dissertations. 217.