Congratulations to Dr. Rafael Mayorga Gonzalez for an Excellent PhD Defense. Rafael has successfully defended his PhD thesis, supervised by Prof. Bert Weckhuysen and dr. F. Meirer.

In his thesis, Rafael studied mass transport in heterogeneous catalysis, recognizing its crucial influence on catalyst activity, selectivity, and lifespan. His research focused on developing new analytical methods to study catalyst pore space using X-ray and fluorescence microscopy. Using transmission X-ray microscopy, he investigated the macroporosity of MIL-47(V) metal-organic framework crystals, revealing micron-scale defects that were later confirmed through focused ion beam cutting and scanning electron microscopy. He developed a cost-effective method using fluorescence microscopy and a PDMS-made microfluidic device to characterize individual porous particles, demonstrating significant heterogeneities among seemingly uniform particles. Rafael explored single-molecule localization microscopy and single particle tracking to map porous catalyst materials with sub-diffraction limit resolution, using a two-dimensional silica model pore system. He investigated quantum dots as local probes in confinement and studied their diffusion behavior under various conditions. His research extended to examining carbon dot probes for exploring smaller pore spaces, particularly in mesoporous materials. Through confocal laser scanning microscopy, Rafael demonstrated that trapping behavior could be modified by adjusting the system’s pH.

Rafael’s PhD thesis is available to read here.