This research project offers new knowledge in the field of artificial patination and extends the application of colour to metals that have previously not been exploited for their colouring properties, specifically pewter and its main constituent, tin. The investigation defines, refines and applies new and evolved processes and techniques that provide novel opportunities for both craft and industry through the development of new products, particularly jewellery and tableware items. The thesis details the actions taken to substantiate the hypothesis that pewter and tin may be coloured by chemical means. This includes the interpretation, exploitation and creative application of developed processes to the design and production of new works. It also discusses the research method applied and the rationales that have informed decision making. The research project is reviewed in separate chapters discussing each phase of the investigation. These phases are:  The selection, testing and analysis of chemical colouring processes within the workshop and laboratory.  Investigation into working properties of the coloured material and surface pattern development.  The creative application of outcomes from the above two phases to new works.  Evaluation of the research outcomes in relation to creative practice and their potential for wider commercial application The chemical exploration and design development phases of the research have been conducted in association with the International Tin Research Institute (ITRI Ltd) and the manufacturing industry, which has confirmed the validity of results. The model of collaboration adopted and associated outcomes are also discussed. Finally, the thesis considers the impact of the research outcomes on the material, creative practice and implications for further investigation including the potential for wider commercial application of the patination procedures developed.

Lithium-alloying anode materials have attracted much attention as an alternative to carbon due to their high theoretical gravimetric capacities (e.g. Li4.4Si: 4200 mAh g-1, Li4.4Sn: 990 mAh g-1, and Li3Sb: 660 mAh g-1). An additional benefit of lithium alloying metals is that some of the react at a higher potentials vs. Li/Li+ than carbon, which can mitigate safety issues caused by solid-electrolyte interface layer formation and lithium plating. One of the most promising lithium -alloying anode materials that are being pursued are Sn-based materials due to their high capacity and tap density. This thesis investigates the synthesis and characterization of Sn-based lithium-ion battery anodes. SnSb-TiC-C and FeSn2-TiC nanocomposite alloy anodes for lithium-ion batteries have been synthesized by a mechanochemical process involving high-energy mechanical milling of Ti/Sn, Ti/M (M = Fe or Sb), and C. Characterization of the nanocomposites formed with x-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) reveals that these alloys are composed of crystalline nanoparticles of FeSn2 and SnSb dispersed in a matrix of TiC and carbon. The SnSb-TiC-C alloy shows an initial gravimetric capacity of 653 mAh g-1 (1384 mAh cm-3), an initial coulombic efficiency of 85%, and a tap density of 1.8 g cm-3. The FeSn2-TiC alloy shows an initial gravimetric capacity of 510 mAh g-1 (1073 mAh cm-3), an initial coulombic efficiency of 71%, and a tap density of 2.1 g cm-3. The TiC-C buffer matrix in the nanocomposite alloy anodes accommodates the large volume change occurring during the charge-discharge process and leads to good cyclability compared to pure FeSn2 and SnSb anodes. / text

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The engineering of a component’s surface is of remarkable importance, it allows applications that surpass what is achievable by the substrate alone by improving surface properties such as hardness, wear and corrosion resistance and even aesthetic value. This project focuses on obtaining bronze coatings through the diffusion of electrodeposited tin on copper via heat treatment. Specifically, the single phase α is targeted due to its attractive properties. Determining the correct heat treatment parameters is crucial since only a specific range of compositions lead to the formation of the desired microstructure and, consequently, properties. The diffusion of a thin coating of tin onto copper often leads to the formation of undesirable features: small craters containing different phases than the one targeted. In the present work, the diffusion behavior of tin-copper couple was investigated; a numerical model was developed to predict the composition profile after heat treatment, which agrees with experimental observations; and the mechanism for the formation of undesirable surface craters during heat treatment was studied and the probable solution proposed. / February 2017

This dissertation examines the transmissions of technology and changes in the culture of statecraft by tracing the itinerary of tin from ore in mines to everyday objects. From the eighteenth century, with the expansion of the Qing empire and global trade, miners migrated from the east coast of China to the southwest frontiers of the Qing empire (1644-1912) and into Southeast Asia, bringing their mining technology with them. The tin from Southeast Asia, in return, inspired Chinese pewter artisans to invent new styles and techniques of metalworking. Furthermore, the knowledge of mining, metalworking, and trade was transferred from miners, artisans, and merchants into the knowledge system of scholar-officials, gradually changing the culture of statecraft in the Qing dynasty. This dissertation explores how imperial expansion and the intensive material exchange brought by global trade affected knowledge production and transmission, gradually changing the culture of statecraft in China. In the Qing dynasty, people used tin, the component of two common alloys, pewter and bronze, to produce objects of daily use as well as copper coins. Thus, tin was not only important to people’s everyday lives, but also to the policy-making of the Qing state. In this way, tin offers an exceptional opportunity to investigate artisans and intellectuals’ approach to technology, while it also provides a vantage point from which to examine how Qing bureaucrats managed the world, a world of human and non-human resources. My dissertation stands at the intersection of the history of science and technology, art history, intellectual history, and the history of global trade. It broadens the scope of the history of science in China by demonstrating how artisans’ practice was crucial to the production of mining treatises. It contributes to the study of science, technology, and society by showing that the transmission of and innovations in technology should be situated in the context of social, cultural, trade, and ecological networks. Finally, I argue that mid-Qing scholars’ efforts to collect practical knowledge changed the culture of governance from Confucian moral didacticism to technocratic epistemology. Qing bureaucrats, Manchu and Han alike, utilized practical knowledge from artisans and merchants in their policy-making process. By emphasizing the entanglement of technology and statecraft, my project contributes to intellectual history and enhances our understanding of the logic of bureaucracy of the Qing empire. My dissertation consists of five chapters. Each chapter uses different methodologies and covers different geographical regions. Chapter One engages with the history of science by demonstrating how scholars translated and codified miners’ vernacular knowledge of mining into mining treatises. Chapter Two examines the semi-autonomous mining community in Yunnan to illustrate that the social organization of miners, which I define as the “social technology” of mining, contributed to the formation of the capital- and labor- intensive mining industry. Chapter Three moves to the island of Bangka (in present-day Indonesia) and focuses on the transmission of mining technology from China to Southeast Asia. Through comparison, I show that the miners in Yunnan and Bangka formed similar (semi-)autonomous social organizations. I argue that it was this social technology that enabled the transmission of Chinese mining technology across geographical regions and laid the foundation for the Chinese dominance of the mining industry in Bangka. The cases of Chinese mining technology in Yunnan and Bangka challenge the modern understanding of technology by showing that technology was not just about tools and machines. Before the 1850s, both Qing bureaucrats and European colonizers considered the social organization of mining to be critical to technological progress. Chapter Four moves back to China to study the formation of Guangdong style pewter. Utilizing visual and material sources, I examine how the introduction of tin from Southeast Asia led to innovations in metallurgy, and how European silver and porcelain inspired stylistic changes. I argue that technology and innovations should be understood in the context of social, economic, material and ecological networks. The final chapter moves to Beijing and Jiangnan area to engage with the institutional history of the Qing empire. Through a case study of monetary reform undertaken in 1740, this chapter reveals that Qing bureaucrats acquired and applied practical expertise to their administrative work. Through their close interactions with artisans and merchants, Qing bureaucrats developed a distinctive vision of statecraft (jingshi). Before the late nineteenth century, the sovereignty of the Qing state was not exercised in the extraction and monopoly over natural resources. Instead, the Qing state relied on the market to acquire most of the natural resources they needed. By focusing on tin, this dissertation shows that the Qing state exercised its political power through material production and paid more attention to the management of skilled labor, capital, and the proper allocation of human and non-human resources.

Porous tin oxide nanotubes were obtained by vacuum infiltration of tin oxide nanoparticles into porous aluminum oxide membranes, followed by calcination. The porous tin oxide nanotube arrays so prepared were characterized by FE-SEM, TEM, HRTEM, and XRD. The nanotubes are open-ended, highly ordered with uniform cross-sections, diameters and wall thickness. The tin oxide nanotubes were evaluated as a substitute anode material for the lithium ion batteries. The tin oxide nanotube anode could be charged and discharged repeatedly, retaining a specific capacity of 525 mAh/g after 80 cycles. This capacity is significantly higher than the theoretical capacity of commercial graphite anode (372 mAh/g) and the cyclability is outstanding for a tin based electrode. The cyclability and capacities of the tin oxide nanotubes were also higher than their building blocks of solid tin oxide nanoparticles. A few factors accounting for the good cycling performance and high capacity of tin oxide nanotubes are suggested. / Singapore-MIT Alliance (SMA)

The reactivity of bulky ligands with various transition metal complexes was studied to better understand the nature of organometallic electronic unsaturation and the role this plays in small molecule activation. A bulky stannyl hydride, tBu3SnH, was synthesized by a revised procedure that is far more facile and reproducible. This sterically encumbered ligand was shown to oxidatively add to a broad range of transition metal complexes, particularly those displaying carbonyl ligands, in greatly differing manners. Reaction of tBu3SnH with Ni(COD)2 and tBuNC was found to yield the mononuclear complex Ni(SntBu3)2(tBuNC)3. This compound possesses photochemical reactivity, most likely attributable to the massive steric bulk surrounding the Ni center, and generates electronically unsaturated metal centered radicals upon photolysis. This complex and its photochemical products were studied from both experimental and spectroscopic aspects. The stable organic radical TEMPO was also reacted with Ni(COD)2 to afford the unsaturated square planar complex Ni(TEMPO)2 which was studied both experimentally and spectroscopically. This deceivingly simple compound displays a wide spectrum of complicated reactivity and small molecule activation which may be utilized in future catalysis.

Titanium nitride coatings have been widely applied and studied as high temperature diffusion barrier for silicon devices in microelectronics, wear resistant coatings in turbine blade materials, and materials for future high temperature nuclear reactors. In order to enhance the material property, superlattices is one of artificially engineered protective coatings, such as AlN/TiN and TaN/TiN multilayered films. Epitaxial cubic multilayer films, TaN/TiN and AlN/TiN nanolayers were grown on Si(001) by Pulsed Laser Deposition (PLD) with various nanolayer thicknesses and number of interfaces. Microstructural studies include X-ray diffraction (XRD), transmission electron microscopy (TEM), and high resolution TEM with ion-irradiation experiments. Electrical, mechanical and thermal property studies were conducted for the interface and size effects on the nanolayers by using nanoindentation and Transient Thermo-Reflectance (TTR) methods. The microstructural and hardness study on TaN/TiN films with ion irradiation (12 keV and 50 keV He ) suggest no obvious microstructural or mechanical behavior change due to ion irradiation. In addition, titanium nitride that serves as effective diffusion barrier to prevent the inter-diffusion between the nuclear fuel and the cladding material was studied in order to enhance the lifetime of the fuels and the reliability of the fuel claddings. The TiN has good adhesion with the stainless steel and higher hardness than that of bulk TiN on the stainless steel. Thermal conductivity test demonstrates that thin TiN film has compatible thermal conductivity as the MA957 and HT-9 bars. The size effect on electrical resistivity is dominant in both of the epitaxial cubic and the polycrystalline TiN thin films in the thickness ranged from ~60 nm down to ~35nm. In the TaN/TiN multilayer, the grain scattering effect on resistivity is dominant rather than interface influence on the resistivity with comparing epitaxial cubic phase and polycrystalline phase. The microstructure and hardness studies of the AlN/TiN multilayer films with He implantation present that the suppression of amorphization in AlN layers and the reduction of radiation-induced softening were achieved in all nanolayer films. Radiation tolerance was found to be size dependent and the layer thickness leading to the highest radiation tolerance was around 10 nm. In addition, the embedded epitaxial cubic AlN with cladding TiN nanolayers showed higher effective thermal conductivity than that of AlN single layer as well as the embedded polycrystalline AlN in the thickness ranged from 10 nm down to 2 nm. It confirms a suppressed size effect, which reduces the amount of decrease in through-plane thermal conductivity.