Nanoparticle-based precursors toward advanced crystalline inorganic solids

Well-defined powder precursors are important for the rational design of crystalline inorganic materials with controlled defects and functional properties. Such powders can be prepared from dried nanoparticles synthesized using a surfactant-assisted/colloidal method that provides precise control over size, shape, composition, and surface chemistry of nanoparticles. These tailored nanoparticles further act as building blocks for three-dimensional assemblies, exhibiting collective nanoscale properties and enabling tailored microstructures of crystalline inorganic materials. However, the programmable engineering of such materials using nanoparticle-based precursors remains limited, due to a lack of fundamental understanding of both the synthesis of nanoparticles and their conversion into macroscopic solids. Furthermore, the formation of three-dimensional assemblies often requires multi-step post-synthetic treatments, which can limit reproducibility and the production of the bulk inorganic materials. In this thesis, I demonstrate a key synthetic parameter governing the formation of desired nanostructures, especially metal/semiconductor core–shell nanoparticles which are potential precursors for engineering composition, crystal structure, and defects of final materials. Then, I investigate their transformative pathways to unveil structural and chemical changes that occur during heat treatment of the nanoparticle-based precursors. Building on understanding of atomic-scale interactions during nanoparticle-based precursor formation, I further demonstrate the possibility of synthesizing the nanoparticle assembly directly in the nanoparticle synthesis reaction and rationalize the process of in situ self-assembly of nanoparticles. Finally, the impact of NP-based precursors on the formation and properties of crystalline inorganic materials is evaluated, demonstrating the potential of employing NP-based precursors for the rational design of functional inorganic materials.