Ceramic Materials Commons^™

Investigation Of Solid-State Reactive Sintering And Rapid Laser Reactive Sintering For Al-Doped Li7la3zr2o12 Solid-State Electrolyte, Aaron Santomauro

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As a society, we’ve exhausted an extreme amount of fossil fuels and put an overwhelming strain on Earth’s natural resources. From this, it is critical to think about the successful future of our planet and ourselves by developing energy devices such as all-solid-state lithium-ion batteries (ASSLIBs). These devices offer a greener and more efficient alternative to power our daily lives, such as electric vehicles (EVs), portable electronics, medical devices, grid-scale energy storage, and aerospace/aviation. ASSLIBs are an excellent alternative to liquid-state batteries, which pose dangerous safety concerns (e.g., flammability, electrolyte leakage, etc.). These ASSLIBs are known to have generally high …

Discovery Of High-Performance Cathode Materials For Protonic Ceramic Fuel Cells, Liang Han

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Environmental pollution and rapid energy consumption have become common problems in global development and will continue to grow with the world population. PCFCs use proton-conducting ceramics as electrolytes, with low activation energy and high ionic conductivity at intermediate temperatures, enabling them to operate at intermediate-temperature conditions, which can effectively solve the problems of poor stability and high cost of exotic materials of traditional solid oxide fuel cells. However, as the operating temperature decreases, the electrocatalytic activity of the cathode decreases significantly, seriously affecting PCFC’s performance. Therefore, developing high-performance cathode material suitable for working under intermediate-temperature conditions has become the key …

The Evolution Of Nanoparticles In Nanoparticle Doped Optical Fibers, Mary Cahoon

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Optical fiber and fiber laser technologies based on silica glass are critical to many technologies today. One method to improve the optical performance of laser fibers is engineer the local environment around the active elements in the glass. To that end, this Dissertation focused on the fabrication and characterization of fibers made with nanoparticles incorporated into the glass to control the local composition. First, the nanoparticle composition and structure was analyzed as it evolved from from the initially-synthesized form to incorporation into the dense aluminum-silicate glass. The aluminum oxide in the glass was found to be important not only to …

Laser Processing Of Multi-Phase Ceramics, Siddhartha Sarkar

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This research explores laser-based processing for multi-phase ceramics, offering a faster, more energy-efficient alternative to conventional ceramic fabrication. Four material systems are explored: silica-titania, alumina-iron, polymer-derived ceramic SiC-gadolinium zirconate, and polymer-derived ceramic SiC-yttrium silicate.

The silica-titania study presents a novel direct CO₂ laser writing approach to fabricating pure silica and silica-titania glasses with exceptional dimensional control and optical transparency, enabling fine spatial resolution, instantaneous consolidation, and eliminating post-heat treatment. Notably, the TiO₂ solubility in the silica network achieved is higher than previously reported, with structures remaining crack-free and transparent up to a specific TiO₂ percentage.

The alumina-iron …

Enhancing Protonic Ceramic Fuel Cells By Advanced Laser Processing For Superior Performance, Tianyi Zhou

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As global temperatures rise, the demand for clean energy solutions intensifies. Protonic ceramic fuel cells (PCFCs) offer advantages like higher conductivity at moderate temperatures (300–700 °C), fuel flexibility, stability, and lower costs. However, traditional PCFC manufacturing faces challenges with interface defects, structural imperfections, and scalability, especially in producing large-area cells and stacks.

This work addresses these issues using advanced laser processing techniques. Laser ablation and direct laser rapid additive manufacturing (DL-RAM) enable precise control of PCFC microstructures, removing surface defects and increasing bonding strength for higher efficiency. Digital layer deposition allows for large-area PCFC single cells and stack production with …

Machine Learning Assisted Discovery Of High-Performance Perovskites For Hydrogen Production, Ximei Zhai

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Hydrogen has significantly contributed to the global energy transition as a clean energy carrier. However, traditional hydrogen production involves energy-intensive processes with heavy carbon emissions. High-temperature water splitting to generate hydrogen has become a promising route for clean hydrogen production. Directly utilizing concentrated solar heat to perform solar thermochemical hydrogen (STCH) production is considered one of the most eco-friendly hydrogen production options. At the same time, high-temperature electrolysis in protonic ceramic electrolysis cells (PCECs) can efficiently utilize intermittent and cost-effective renewable electricity to produce hydrogen. Perovskite oxides with good redox capability and tolerance for oxygen deficiency are considered the most …

A Transport Property-Based Assessment Of Triple Ionic-Electronic Conductors As Cathodes For Protonic Ceramic Fuel Cells, Jack Harrison Duffy

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Triple ionic-electronic conductors (TIECs) are a widely studied class of materials for electrodes in ceramic electrochemical devices such as protonic ceramic fuel cells. These ceramics are perovskite-based and exhibit concurrent conductivity of protons, oxide ions, and electrons at elevated temperatures. Despite their numerous references in literature, few studies have systematically probed the fundamental surface- and bulk-level properties of TIECs. In this dissertation, dopant levels are systematically altered in the BaCo_0.4Fe_0.4Zr_0.1Y_0.1O_3-δ-type perovskite TIEC to reveal the effects on structure, transport properties, and durability of each material. The results of this work …

Synthesis Of Monodisperse Nanoscintillators At High Temperatures For Biomedical Relevant Applications, Eric Zhang

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Luminescent sub-100 nm particulates continuously generate immense research interest in the biomedical field for imaging, theranostics, and optogenetics. Conventionally, upconversion nanoparticles or UV activated semiconductors are studied, however these materials are limited by biological barriers such as the skin which reduces the penetration depth of these excitation sources, tissue's auto- fluorescence, and toxicity. One approach to overcome these challenges is to use nanoscintillators (sub-100 nm materials that can generate visible light using high energy excitation sources such as x-rays) which can generate light locally to the human body. Numerous scintillators have been reported since the discovery of x-rays from the …

Deep Learning-Guided Prediction Of Material’S Microstructures And Applications To Advanced Manufacturing, Jianan Tang

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Material microstructure prediction based on processing conditions is very useful in advanced manufacturing. Trial-and-error experiments are very time-consuming to exhaust numerous combinations of processing parameters and characterize the resulting microstructures. To accelerate process development and optimization, researchers have explored microstructure prediction methods, including physical-based modeling and feature-based machine learning. Nevertheless, they both have limitations. Physical-based modeling consumes too much computational power. And in feature-based machine learning, low-dimensional microstructural features are manually extracted to represent high-dimensional microstructures, which leads to information loss.

In this dissertation, a deep learning-guided microstructure prediction framework is established. It uses a conditional generative adversarial network (CGAN) …

Investigation And Characterization Of New Optically Stimulated Luminescence (Osl) Dosimetric Materials, Linyu Pan

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Optically stimulated luminescence (OSL) dosimeters have attracted increasing attention due to advantages over TL dosimeters, including no thermal quenching and higher sensitivity. Nevertheless, currently, there are only two commercially available OSL dosimeters, BeO and Al₂O₃:C. An OSL dosimeter requires low effective atomic number (Z_eff < 16), at least one type of recombination center and one type of trap, and UV~blue emission. In this dissertation, motivated by the search of new OSL dosimetric materials, a systematic investigation of alumina (Z_eff = 11.3) and magnesium aluminate spinel (Z_eff = 11.2) based materials was performed in terms of the engineering of the recombination centers and electronic traps. Microstructural characterization was executed by means of X-ray diffraction (XRD) and Raman spectroscopy. Luminescence was characterized under X-ray excitation (radioluminescence; RL) at ambient and …