Nanoconfinement Guided Synthesis and Assembly of Metal-2D Material Catalytic Heterostructures

Abstract

This dissertation introduces novel strategies for the synthesis and assembly of 2D materials (2DMs) into functional heterostructures, leveraging metal ion interactions and nanoconfinement effects. It details the creation of noble metal ion (NMI)-crosslinked 2DM hydrogels and the development of NMI-complexed 2DM inks. A key contribution is the introduction of the Metal Ion Release Assembly (MIRA) process, a versatile and scalable method for depositing thick and uniform 2DM coatings on complex surfaces using metal ion-loaded gelatin hydrogels. This technique allows for tunable coating thickness by controlling parameters such as metal ion concentration and 2DM dispersion concentration.Furthermore, the dissertation presents a novel electrostatic assembly process guided by vacuum filtration for the synthesis of catalytic metal nanocrystals, specifically platinum (Pt), within the interlayer confined spacings of 2DMs like graphene oxide (GO) and MXene. This method enables controllable Pt loadings and influences the size, distribution, and morphology of the resulting Pt nanocrystals by manipulating the concentration of the tetraammineplatinum(II) nitrate (TPtN) precursor and water removal techniques such as air-drying and freeze-drying. The synthesized Pt–2DM heterostructures demonstrate substrate-dependent catalytic activities in reactions like 3-nitrostyrene and phenylacetylene hydrogenation. Beyond catalysis, the dissertation showcases the broader applications of 2DM assemblies, including anti-counterfeiting technologies utilizing unclonable MXene topographies and the use of machine learning to accelerate the design of sustainable biobased packaging, ultrastretchable electronics, and nerve-on-a-chip platforms. This comprehensive work enhances the fundamental understanding of metal-2DM interactions and establishes new, scalable fabrication strategies for high-performance materials relevant to energy, environmental solutions, and advanced manufacturing.