Alfred University Research & Archives

The Alfred University Research and Archive (AURA) repository collects, distributes and preserves research and scholarship created by faculty, staff and students as well as documents of historical or archival significance. By offering a central location for depositing these materials through a stable, well-managed and permanent platform, AURA provides the Alfred University campus with the opportunity to share research with colleagues throughout the world while also providing access to documents with enduring value. AURA is managed by the Alfred University Libraries; additionally users should be aware of the Terms of Use and Rights Statement.

 

Recent Submissions

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Next Generation Hydroxyapatite Bone Grafts: Copper-Inclusion and Photocurable Composites
(New York State College of Ceramics at Alfred University. Inamori School of Engineering., 2023-12) Kucko, Sierra; Keenan, Timothy; Sundaram, S.K.; Clare, Alexis; Wren, Anthony
Orthopedic infection is a massive threat whose prevalence and invasiveness increases in parallel to a rapidly aging population. The rise in antibiotic-resistance deepens this threat to a level where infection is projected to become a leading cause of death in the next two decades, thus substantiating the need for alternative therapies. A shift from treatment solutions towards prophylactic practices will likely pave the way for the next generation of bone grafts. Hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP), the most widely used bone grafting materials clinically, do not have any inherent antimicrobial properties. Transition metals, such as Cu, are known to be antibacterial and have thus been incorporated into HA or β-TCP for that purpose, which is the motivation for the following work. Since ceramic particles are typically delivered as a grafting material in composite form, a wide range of HA- and β-TCP-polymer composites are reviewed extensively, including the various fabrication methods that have been developed recently. Clinically implemented composites are surveyed, with commercially available products and their respective uses highlighted. Robust structural and chemical analysis of these types of materials is severely lacking, which limits our understanding of their antibacterial nature and leaving some conclusions to be drawn based upon conjecture. Our fundamental understanding of any antibacterial effect relies on the understanding of the tenancy of substituted ion(s) and its correlation to key physical, structural, and chemical properties. This gap in knowledge leaves room for a substantial body of work designed to explore Cu-inclusion in an HA lattice. Motivated by this, a series of Cu-containing HA (CuHA) was synthesized via aqueous co-precipitation. This work tracks changes in lattice parameters with increased Cu content, conducted through Pawley fits of X-ray powder diffraction (XRD) patterns. High-temperature in situ XRD followed by quantitative phase identification assessed the thermal transition to Cu-containing β-TCP. As Cu target incorporation increased from 0-5 mol% (actual 0-1.96 mol%), there was an observable increase in stoichiometry, carbonate removal, and resistance to thermal phase transition. Particle size, surface area, and degree of crystallinity measurements revealed significant deviation in surface area corresponding to only a 1.96 mol% increase in Cu content, yet miniscule modifications to crystallinity and particle size were observed. Heat treatment of CuHA to form Cu-containing biphasic calcium phosphate (CuBCP) enabled Cu release in aqueous solution whereby its CuHA counterpart showed no Cu release. Agar diffusion and time-based bacterial broth analyses were conducted against gram-positive and gram-negative strains of bacteria for CuHA and CuBCP. Some key structure-property relationships have been identified through this work. Calcium phosphates, albeit adept at repairing hard tissue, are limited to non-load-bearing sites. Additionally, they are difficult to retrofit in the often unusually shaped bone defects. Ceramic-polymer composites are a better biological mimic of bone tissue, which itself is a composite. Polymerized high internal phase emulsion (polyHIPE) is a stochastic fabrication process that elicits highly interconnected and porous scaffolds, ideal for bone tissue regeneration. A 4-armed star-shaped photocurable polycaprolactone (PCL) is synthesized and functionalized with methacrylate end-groups to be used for UV-cured polyHIPE. The resultant polymer is characterized via Raman spectroscopy, attenuated total reflection- Fourier transform infrared spectroscopy (ATR-FTIR), and mass spectrometry (MS) to gain insight into the architecture of the macromolecule. Cured polyHIPEs exhibited excellent porosity, open-cell morphology, and interconnectedness, with pore size diameter of 108 ± 57μm. Efforts culminated with the attempted manufacture of a proof-of-concept next-generation bio-composite by incorporating HA into the polyHIPE. HA underwent surface modification to improve dispersion in the oil phase. However, HA caused a complete phase inversion of the emulsion. Nonetheless, the star-shaped PCL is characterized and this proof-of-concept bio-composite is described.
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The Effects of Residual KNO3 and Ion Exchange Induced Crack Closure on Indented Glass
(New York State College of Ceramics at Alfred University. Inamori School of Engineering., 2023-11) Tindle, Madison; LaCourse, William; Möncke, Doris; Clare, Alexis
The objective of this body of work is to investigate the fatigue response of ion - exchanged aluminosilicate glass containing pre-exchange indentation flaws. Previous work found that residual potassium nitrate (KNO3), the ion exchange material, remained in the flaw after an initial washing of the parts. The remaining material at the flaw tip is thought to prevent humidity or water from penetrating to the crack tip and slows crack propagation thus increasing the failure load. To test this hypothesis two flaw depths of 25μm and 90μm, and three washing conditions were tested after the parts were ion-exchanged at the same time and temperature. The first condition is the control set where the samples just underwent an initial washing to remove salt on the surface post ion exchange. The second condition was ultrasonic cleaned. The third condition was also ultrasonic cleaned and mineral oil was added to the flaw to act as a humidity barrier. The fatigue response for each condition was evaluated using a ring-on-ring method at varying strain rates to calculate the fatigue response. The sample with small flaws around 25μm in depth showed no difference in fatigue response between the control and just ultrasonic cleaned. The driving force for the increased strength is from the ion exchange at the flaw tip and not the material left in the flaw acting as a humidity barrier. The samples with the larger flaws around 90μm did show some variation in the failure mechanism and failed at low loads that were closer to the non-ion-exchanged failure loads. When these parts were looked at under SEM NaCl was found on the surface of the flaws, which led to some exploration in diffusion time, expansion, and contamination during the ion exchange process. The crack width was estimated to evaluate the volume of salt in the flaw as well as determine the feasibility of the crack closure. The two most plausible hypotheses were the salt refresh rate or contamination. Further testing is needed to answer these questions.
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Additive Manufacturing of Hybrid Composites for Flexible Electronic Application
(New York State College of Ceramics at Alfred University. Inamori School of Engineering., 2023-08) Gao, Yuqi; Ding, Junjun; Wu, Yiquan; Wren, Anthony; Tidrow, Steven
Material extrusion 3D printing is capable of fabricating complex macrostructures and designing microstructures for next-generation flexible electronics. Thick electrodes are promising to increase the mass loading of active materials in supercapacitors, but the 3D geometries and microstructures in thick electrodes still hinder the development with high electron and ion exchange rate and accessible active sites. The scaffold 3D electrodes of reduced graphene oxide:manganese oxide/carbon nanotube (rGO:MnOx/CNT) with highly-ordered microstructure were manufactured by material extrusion 3D printing, freeze-drying, and thermal treatment. The increasing amount of MnOx/CNT composites improved the areal capacitance. And the rate capability remained stable at different thicknesses. A 2 mm thick rGO:MnOx/CNT (weight ratio 5:3) electrode exhibited an excellent area capacitance contributed by the highly ordered rGO networks. Fiber-shaped supercapacitors are attractive as an energy storage unit due to their excellent flexibility. However, fabricating robust fibers with large yields remained a challenge. The present study fabricated the core-sheath fibers through coaxial extrusion printing. Carboxymethylcellulose sodium salt (CMC) slurry with controlled rheological properties was extruded from the outer channel, while GO slurry was extruded from the inner channel simultaneously. The followed freeze-drying process protected GO sheets from agglomeration, providing more efficient chemical reduction. After reduction, rGO sheets were separated and expanded to fill in the CMC sheath, which eliminated the delamination between the CMC sheath and rGO core. Apart from the 1D core-sheath fiber electrode, 3D printed electrode with core-sheath structure provided a solution for the development of thick supercapacitors. Specifically, 3D thick rGO/CNT-rGO/CNT/MnO@CNT (rGC-rGCMC) electrodes with controlled lattice architectures, core-sheath structure, and hierarchical porosity were prepared. The electrodes with different volume ratios of core to sheath, including 100%-0%, 0%-100%, 20%-80%, 30%-70%, 40%-60%, and 50%-50%, were investigated to explore the influences of core-sheath structure on thick electrodes. All capacitance decays from core-sheath electrodes (20%-80%, 30%-70%, 40%-60%, and 50%-50%) were smaller than rGCMC (0%-100%) electrodes, indicating the improved rate capability from the core-sheath structure. Compared 30%-70% core-sheath electrodes with electrodes made of homogenous 30% rGC and 70% rGCMC mixture (30%+70%), lower capacitance (382.27 mF cm^-2 and 25.66 F g^-1 at 0.5 mA cm^-2) of 30%+70% mixture electrode without core-sheath structure suggested less efficiency to harvest electrons from the redox reactions. Electrochemical impedance spectroscopy (EIS) data further supported and explained the resistances of thick electrodes with different volume ratios.
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Nanoscale Dipole Engineering of BaTiO3 Using Dy3+-Ta5+ and Ho3+-Ta5+ Dipole Pairs
(New York State College of Ceramics at Alfred University. Inamori School of Engineering., 2023-05) Pellegrino, Victoria; Tidrow, Steven; Pilgrim, Steven; Sundaram, S.K.
Barium titanate (BaTiO3) is the most widely used base material for electroceramic capacitor technology. Previously, experiments conducted within the New York State College of Ceramics (NYSCC) Laboratory for Electroceramics (LEC) at Alfred University have demonstrated that substituting dipole pairs for the titanium ion in the center of the octahedral cage in BaTiO3 can enhance the electrical properties of the material for storing charge and provide the enhanced properties over a larger operating temperature range as compared with pure BaTiO3. This thesis investigates the properties of BaTiO3 - based material processed using dipole engineering at the nanoscale, through substitution of Dy3+-Ta5+ and Ho3+-Ta3+ dipoles for Ti4+, to form Ba(Dy,Ta)xTi1-2xO3 and Ba(Ho,Ta)xTi1-2xO3, respectively. The dipole pairs maintain charge neutrality, but desirably possess higher polarizability values than the original Ti4+ ion; thereby, leading to enhancements in electrical properties. The substitutions were performed through a solid-state reaction following the stoichiometric equation: Ba(Ḇ3+, Ta5+)xTi1-2xO3, with x = 0.0000, 0.0025, 0.0050, 0.0100, 0.0250 and 0.0500, and Ḇ being the Dy3+ or Ho3+. The material properties were investigated using room temperature and energy dependent characterization tools to improve understanding of the effects of dipole pair substitutions, including concentration dependence. Material characterization has been completed using: room temperature x-ray diffraction to determine room temperature structure, phase purity and lattice parameter; temperature dependent resistivity to determine intrinsic material resistivity and activation energy; impedance - inductance - resistance (LCR) to determine temperature and frequency dependent relative permitivity; temperature dependent Raman to determine thermally induced structural phase transitions; and, scanning electron microscope to determine microstructure, and grain size. Analysis indicates that a range of a priori predicted properties, using the new simple material model (NSMM) as well as projections from prior results, occur. Further, novel Raman properties are also observed, including a BaTiO3 - like lattice and a second lattice associated with either the individual ions Dy3+ and Ho3+ or the Dy - Ta and Ho - Ta dipole pairs within Ba(Dy,Ta)xTi1-2xO3 and Ba(Ho,Ta)xTi1-2xO3, respectively. Importantly, a decoupling of the relative permitivity peak from the structural phase transition temperature is demonstrated.
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Manipulation of Lanthanoid Luminescence in Silicates
(New York State College of Ceramics at Alfred University. Inamori School of Engineering., 2023-06) Bellows, Charles; Clare, Alexis; LaCourse, William; Loucks, Roger; Möncke, Doris
The luminescent properties of several lanthanoid ions were examined when doped into silicate glasses. Moreover, the effect of visible colorants, common in the world of glass art, on said luminescence was studied. Several potential applications are described, including aesthetic uses in the realms of art and industry. Luminescent microsphere production as an add-value sink for waste glass is detailed and a novel process was developed to incorporate persistent luminescent material into waste glass and other 'previously melted' glasses via a 'sinter-esque' fusion method with promising results. A glass with a unique dopant combination was developed to showcase a visible color contrasted with a UV-induced luminescent color. Glass medallions utilizing this composition were manufactured for use in the podium medals of the 2023 FISU World University Games Winter. Additionally, a specific case study was investigated regarding one of the lanthanoid-transition metal codopant compositions. The combination of cerium and manganese ions in silicate glass composition exhibits a novel optical effect: luminescent opacity. Under visible light illumination, this composition appears transparent purple; similar to other silicates containing the Mn3+ ion. As with other silicates doped with Ce3+ and Mn2+ ions, this composition also luminesces visible light under ultraviolet light. Unlike similar compositions, under said ultraviolet light the glass acquires a turbidity not seen under visible light. when the ultraviolet source is removed, the glass returns to a transparent purple rather than maintaining its opacity.