UC Berkeley

This dissertation explored the innovative avenues for the confinement growth of materials, leveraging both space-confined and area-selective synthesis strategies through a variety of interface engineering approaches. It highlighted the multifaceted roles of the interface during the synthesis process, acting not only as a nanoreactor and/or a physical scaffold to constrain the geometry of the resulting materials, but also setting a specific chemical microenvironment. This environment is instrumental in facilitating the confined nucleation, growth, and stabilization of intermediates or final products, a process pivotal to area-selective synthesis. Towards it, we first focused on the intercalation of large molecules, such as P2O5, through the basal plane of graphene. This process yielded a confined P2O5 and/or metal phosphate structure within the graphene/Ge (110) heterointerface, following a two-step mechanism. This mechanism involved the dissociation of P2O5 and the subsequent intercalation of its fragments, as corroborated with density functional theory (DFT). The focus was then turned to area-selective synthesis of materials by engineering the surface energy profile at the vacuum-liquid and/or graphene/diamond like carbon (DLC) interface. In one study, a complex surface energy profile was achieved at liquid metal-vacuum interface using Laguerre-gaussian (????) lasers as the heat source, which induced novel Marangoni flow pattern. Marangoni surface flow, and convective flow in bulk liquid metal directed the movement of microparticles within the liquid, demonstrating that careful tuning over the parameters of the ???? laser (i.e., laser mode, spot size, and intensity of the electric field) allowed for precise control over the structure of the ring-shaped particle assemblies at solid-liquid interface. Finally, this dissertation presented a novel method for tuning the work function of monolayer graphene across a broad temperature range. This was achieved through engineering the graphene-Ga implanted DLC heterointerface, allowing for bipolar tuning (either increase or decrease) of the local work function landscape of graphene up to 500°C. This comprehensive study established a clear link between interface engineering and the confinement growth capabilities of materials, offering new strategies and advanced understanding for confinement materials synthesis.