Glasses and Optical Materials: Current Issues and Functional Applications: Cooper Distinguished Lecture
Sponsored by: ACerS Basic Science Division, ACerS Glass & Optical Materials Division
Program Organizers: Doris Möncke, Alfred University; Mathieu Hubert, Corning Incorporated
Tuesday 8:00 AM
October 11, 2022
Room: 412
Location: David L. Lawrence Convention Center
Session Chair: Steve Martin, Iowa State University
8:00 AM Invited
Uncovering Hidden Glasses: Liping Huang1; 1Rensselaer Polytechnic Institute
Glasses are primarily made by cooling liquids fast to avoid crystallization, but finite cooling rates limit the range of compositions that can form glasses. Recent studies show that pressure can provide different pathways to uncover hidden glassy states with unique structure and properties that are unattainable from melt quenching. In other words, pressure allows the retention of kinetically stable atomic configurations such as higher coordination states that cannot be formed by using temperature and time as the control variables. Furthermore, pressure can change the structure and properties of glass dramatically and tune them continuously for a given composition, thus adding another dimension to vastly expand the glassy states. Attractive properties including high elastic modulus, high hardness, enhanced ductility, high thermal-mechanical stability and reduced optical loss and dispersion, have been observed in pressure-processed glasses. Structure of such glasses will be compared with those from melt quenching, to understand their unique properties.
8:40 AM Invited
Lithium-iron Silicate Glasses as Simulations of High-Fe Nuclear Waste Glass: Jessica Sly1; John McCloy1; 1Washington State University
Understanding the complexities behind crystallization and resulting properties of simulated nuclear waste glasses and glass ceramics provides critical insight to the performance of glass for long-term nuclear waste storage. Specifically, the effect of additional Fe2O3 on crystallization may be an important consideration in vitrification of certain wastes. Previous research has shown that compositions simultaneously high in Li and Fe tend to crystallize oxide phases containing both these metals. A standard melt-quench technique was implemented to synthesize glasses with compositions LiFeSiO4, LiFeSi2O6, and LiFeSi3O8. X-ray Diffractometry (XRD), Differential Thermal Analysis (DTA), and Vibrating Sample Magnetometry (VSM), were used to observe crystallization behavior. A lithium iron oxide phase was detected using XRD for all samples melted at 1300°C but was most prominent in the LiFeSiO4 glass. The thermal measurements revealed crystallization and an increase in glass transition temperature as the silicon to iron ratio increased in the glass series.
9:00 AM Invited
Utilizing Electrical Impedance Spectroscopy (E.I.S.) to Observe In-situ Phase Changes in Lithium Diborate Glass Undergoing Thermal Relaxation: William Guthrie1; Caio Bragatto1; 1Coe College
Electrochemical impedance spectroscopy (E.I.S.) is a powerful tool for analyzing the electrical and ionic properties of solid state ceramics and glasses as a function of frequency. In this work, E.I.S. was used to monitor the changes in ionic conductivity during the thermal relaxation of lithium diborate glass. Since the conductivity of a material (ó in S cm-1) is proportional to the phase’s geometric factor and inversely proportional to the sample’s resistance (1/R l/A), it becomes possible to measure the relative volume of each phase present within the sample. By repeating these tests at a regular interval while a sample is held at a high temperature below the glass transition temperature, the process of relaxation can be observed in real time.
9:20 AM Invited
Multispectroscopic Study of Lead Borate Glasses: Ian Slagle1; 1Coe College
A wide range of binary lead borate glasses (30 ≤ x ≤ 80 mol % PbO) were studied with Raman, 11B magic angle spinning nuclear magnetic resonance (NMR), and 207Pb static NMR. The 207Pb NMR anisotropic chemical shift interaction was analyzed using a new program that utilizes approximate Bayesian computations on the extended Czjzek model, which models glass disorder. Quantification of the boron environment from 11B MAS NMR through DMFit and semi-quantitative Raman analysis were also performed. This work finds 1) lead borate glasses with high lead concentrations approach structures similar to lead oxide crystals, 2) further evidence of the mixed role of lead as a network former and modifier, and 3) under-modification of the borate network.
9:40 AM Invited
Structure-property Relationship in Mixed Oxy-sulfide Glassy Solid Electrolyte Material: 0.58Li2S + 0.42 [(1–y)SiS2 + yLiPO3]: Presley Philipp1; Victor Torres III1; Steve Martin1; 1Iowa State University
Mixed oxy-sulfide (MOS) glassy solid electrolytes (GSE) have proved to be a strong contender for use in solid-state batteries because of their high ionic conductivity and electrochemical stability. The MOS series 0.58Li2S + 0.42[(1-y)SiS2 + yLiPO3] (y = 0.0 – 0.5) was prepared via melt quench-synthesis. Differential scanning calorimetry (DSC) was used to determine the glass transition and crystallization temperature of these glasses. To characterize the structure, Fourier Transform Infrared Spectroscopy (FTIR), Raman Spectroscopy, and 29Si & 31P Magic Angle Spinning NMR spectroscopy (MAS NMR) were employed. Electrochemical Impedance Spectroscopy (EIS) was used to determine the d.c. Li+ ionic conductivity of the GSEs and show that the conductivity increases from an initial value of 1.03 x 10-3 for the y = 0 GSE to a maximum value of 1.33 x 10-3 S/cm for the y = 0.1 GSE, which is indicative of a positive mixed glass former effect.