This thesis describes in-depth studies of the remarkable electronic transport within the ultrahigh conductivity delafossite metals PtCoO_2 and PdCoO_2 using the tool of focused ion beam (FIB) microstucturing. Despite being first synthesised over 50 years ago, important questions remain regarding both the origin of the unusually high conductivity of these compounds and the consequences of their unique properties for unconventional electronic transport, such as that within the ballistic regime. The thesis explores both these areas.

High-energy electron irradiation is used to examine...

This book introduces readers to the preparation of two-dimensional metal sulfide/oxide for CO₂ photoreduction. Based on two-dimensional metal sulfide/oxide materials, this book establishes the structure-to-property relationships of photocatalyst for CO₂ photoreduction, and reveals the intrinsic mechanism of the CO₂ photoreduction by virtue of the in situ characterization techniques and the density functional theory calculations. It is anticipated that this book will help to identify empirical guidelines for designing and fabricating high-performance...

Line intensity mapping (LIM) is an observational technique that probes the large-scale structure of the Universe by collecting light from a wide field of the sky. This book demonstrates a novel analysis method for LIM using machine learning (ML) technologies. The author develops a conditional generative adversarial network that separates designated emission signals from sources at different epochs. It thus provides, for the first time, an efficient way to extract signals from LIM data with foreground noise. The method is complementary to conventional statistical methods such as...

This book describes a detailed multi-scale approach integrating nano- (active site), meso- (porous catalyst architecture) and macroscale (reactor) efforts, to address the challenges of producing a better epoxidation catalyst.

It contains an in-depth study of the design and synthesis of gold nanoparticles and their application as a catalyst for direct gas phase propylene epoxidation. “Direct” means using only hydrogen and oxygen in one step, which is key for sustainable manufacturing, as opposed to commercialised, more complex production routes requiring multiple steps, or...

The thesis contains several pioneering results at the intersection of state-of-the-art materials characterization techniques and machine learning. The use of machine learning empowers the information extraction capability of neutron and photon spectroscopies. In particular, new knowledge and new physics insights to aid spectroscopic analysis may hold great promise for next-generation quantum technology. As a prominent example, the so-called proximity effect at topological material interfaces promises to enable spintronics without energy dissipation and quantum computing with fault...

This thesis provides the first atomic length-scale observation of the structural transformation (referred to as lattice reconstruction) that occurs in moiré superlattices of twisted bilayer transition metal dichalcogenides (TMDs) at low (θ < 2˚) twist angles. Such information is essential for the fundamental understanding of how manipulating the rotational twist-angle between two adjacent 2-dimensional crystals subsequently affects their optical and electrical properties.

Studies using Scanning transmission electron microscopy (STEM), a powerful tool for atomic-scale imaging,...

This book presents novel contributions in the development of solid-state-transformer (SST) technology both for medium-voltage (MV) and low-voltage (LV) utility grid interfaces, which can potentially augment the grid modernization process in the evolving power system paradigm. For the MV interface, a single-stage AC-DC SST submodule topology has been proposed, and its modulation and soft-switching possibilities are analysed, experimentally validated and adequately benchmarked. A control scheme with power balance capability among submodules is developed for MV grid-connected single-stage...

This open access book is devoted to the theoretical and experimental studies of a novel accelerator light source mechanism called steady-state microbunching (SSMB) which promises high-power, high-repetition rate, narrow-band coherent radiation in an electron storage ring. The contribution of this dissertation consists of three parts: first, answers the question of how to realize SSMB from a beam dynamics perspective; second, reveals what radiation characteristics can we obtain from the formed SSMB; and third, experimentally demonstrates the working mechanism of SSMB in a real machine for...