Development of hierarchically structured porous particles and surfaces

Porous materials are indispensable in modern technology, with applications spanning catalysis, energy conversion, separation systems, and advanced surface engineering. In this thesis, we present strategies for the design and scalable production of hierarchical structured porous particles with tunable porosity, surface roughness features, and mechanical stability, and demonstrate their potential across diverse applications. We first explore the synthesis of large-pore mesoporous primary particles by incorporating renewable, bio-based pore expander limonene and validate their effective use as a replacement of conventional fossil-based expander trimethylbenzene. Using spray drying, we then control scalable fabrication of supraparticle powders with hierarchical pore networks spanning meso- to macro-scales. The supraparticles are then employed as model systems to study the role of surface roughness in liquid marble systems, where rougher supraparticles enable stabilization of lower surface tension liquids and enhance mechanical robustness. Next, we develop environmentally benign, scalable superhydrophobic coatings by spray-coating supraparticles, and optimized durability through a combination of binder addition and thermal sintering strategies. The tunable pore networks of supraparticles are further employed as supports in catalytically active liquid metal solutions (SCALMS) for propane dehydrogenation, where pore size and structure are found to govern droplet immobilization and catalytic stability. We investigate the structure-property relation of stationary phase materials in nanoparticle chromatography using supraparticles as model stationary phases. Finally, we introduce a new method to produce hierarchical porous particles with open, accessible pore networks via polymerization-induced spinodal decomposition method in emulsions, overcoming limitations of dense shell formation in such systems.