Microscopic diffusion measurements with nanoporous materials: complementary benefits of infrared microimaging and pulsed field gradient NMR

This cumulative dissertation is a compilation of eight peer-reviewed, published scientific papers on the subject of two microscopic techniques of diffusion measurement, namely infrared (IR) microimaging and pulsed field gradient (PFG) NMR. The dissertation contains mainly five chapters. The first chapter introduces diffusion phenomena in general and concisely explains the importance and the current challenges of the investigation of molecular diffusion in nanoporous materials, which are the primary motivations behind the present work. To rise the challenges, it proposes an option of employing IR microimaging in parallel with PFG NMR in the measurement of the molecular diffusion. The second chapter describes the basic principles of the two diffusion measurement techniques and what they are capable of. Chapters 3 and 4 deliver convincing demonstrations of their applicability and potential in diffusion studies. Lastly, Chapter 5 concludes the present work by discussing complementary benefits of the two techniques, along with the novel application of the two-region model for assessing mass transfer in hierarchically porous materials.

Level thesis:degree_level

thesis.doctoral

Grantor dc:publisher

Universität Leipzig

Year

2020

Author dc:creator

• Hwang, Seungtaik

• diffusion
• nanoporous material
• infrared microimaging
• pulsed field gradient NMR