Hierarchical porous metal-organic frameworks (MOFS): design, synthesis, and their application as gas adsorption materials

Official URL: https://risc01.sabanciuniv.edu/record=b2486387 _(Table of contents)

Climate change is a global concern and interacts with economics, energy, and environment. Alternative energy resources are necessary to act towards global climate change and to produce energy in a sustainable way. In this Ph.D. thesis, hierarchical porous MOFs were designed to enhance the CO2 and H2 adsorption capacities of traditional MOFs. Hierarchical porous MOFs were synthesized via a perturbation assisted nanofusion synthesis strategy at which the sizes of textural pores were controlled by metal to linker ratio and synthesis temperature. Formation of hierarchical pores enhanced the BET surface areas and total pore volumes and the highest of all the reported BET surface areas and the pore volumes for MIL-88B and Fe-BTC are achieved. Introducing hierarchical porosity to the pore structure enhanced the measured CO2 and H2 adsorption capacities at 298 K. The achieved CO2 and H2 adsorption capacities (298 K and 1 bar) are higher than those of previously reported ones for MIL-88Bs and Fe-BTCs. The enhanced gas adsorption capacities are attributed to the ultramicropores present in the pore structure which have higher binding energies than the wider pores. This Ph.D. study experimentally proves the necessity of ultramicropores in the gas adsorption studies (at 298 K), reports an effortless, and feasible synthesis strategy that can form hierarchical pores and enhance the textural properties and gas adsorption capacities measured at 298 K. This study paves the way for the design of hierarchical porous MOFs and leads the way for the use of hierarchical porous MOFs in gas adsorption studies