Materials Chemistry Commons^™

Raw Data For The Manuscript "Silicon-Stabilized Three-Dimensional Covalent Networks In High Entropy Diborides", Michael Yeung, Reza Mohammadi

Chemistry Department Faculty Scholarship

Abstract for data:

Raw data for the journal publication, Silicon-stabilized three-dimensional covalent networks in high entropy diborides. ReadMe file provided.

Abstract for Journal publication: 

High entropy ceramics offer a pathway to stabilize unconventional chemistries beyond traditional alloying rules. We report the incorporation of silicon into an AlB₂-type high entropy diboride, Cr_0.2Nb_0.2Si_0.2Ta_0.2Ti_0.2B₂, despite silicon violating classical Hume-Rothery rules for alloying. Arc melting produced a phase-pure, chemically homogeneous structure, as confirmed by powder X-ray diffraction (pXRD) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM–EDS). Silicon occupies …

Raw Data For Violations Of Coordination: Exploring Metastable Diborides For Energy Storage, Michael Yeung

Chemistry Department Faculty Scholarship

The ideal aeronautical solid-state fuel should possess a high density (more thrust per Newton’s Third Law), high gravimetric heat of combustion (more energy for less weight), and a high volumetric heat of combustion (more room for mission-critical items). In this work, manganese diboride (MnB2) demonstrates a high density of 5.3 g/cm3, a high gravimetric heat of combustion of 38.30 kJ/g, and the highest volumetric heat of combustion of any known fuel of 202.99 kJ /cm3. When compared to the currently used fuel in Space Shuttle rocket boosters and the Space Launch System, aluminum metal, MnB2 represents a 100% increase in …

Raw Data For Tailoring High Entropy Borides For Hydrogenation: The Influence Of Crystal Morphology And The Exploration Of Catalytic Pathways, Michael Yeung, Ting Wang

Chemistry Department Faculty Scholarship

The high entropy boride (HEB) Al0.2Nb0.2Pt0.2Ta0.2Ti0.2B2, with its unique crystal structure and high coordination (platinum coordinated to 12 borons), has been shown in our previous work to exhibit exceptional catalytic properties, especially in sulfur-rich environments, where traditional platinum catalysts would succumb to sulfur-poisoning. In this work, we investigate the mechanism of the HEB catalyst, first by comparing the synthesis by flux growth, as previously reported, to an arc melted preparation. It is evident that the aluminum flux growth synthesis encourages the growth of single crystals, with clear and defined crystal facets, whereas the arc melted sample results in poorly defined …

Raw Data For A Mild Alkaline Hydrothermal Etchant For Mbene Exfoliation, Michael Yeung

Chemistry Department Faculty Scholarship

Abstract for data:

Raw data for the journal publication, A Mild Alkaline Hydrothermal Ethant for MBene Exfoliation. ReadMe file provided.

Abstract for journal publication:

MoBene (the boride equivalent of MXenes) has been a synthetic challenge because borides degrade in common etching media. Inspired by the intercalation of lithium ions into AlOOH, we hypothesized that a hydrothermal route enables lithium ions to intercalate the aluminum layer of MoAlB and further separate the MoB sheet apart. Here, MoBene is first synthesized through a mild hydrothermal etching method with dilute lithium hydroxide. X-ray diffraction showed a peak at 8.9°, confirming an exfoliated layered …

Raw Data For High Entropy Stabilized Platinum Diborides For Poison-Resistant Catalysis, Michael Yeung, Ting Wang

Chemistry Department Faculty Scholarship

Raw data for the publication High-Entropy-Stabilized Platinum Diborides for Poison-Resistant Catalysis including Powder X-ray Diffraction and Nuclear Magnetic Resonance data.

Abstract for publication:

Alloying and solid-solution formation is a powerful technique that enhances and adds properties through elemental mixing, but unfortunately, some elements simply cannot mix as their chemical nature prevents a thermodynamically stable structure. For example, the inherent nobility of platinum group metals does not favor bond formation and precludes their incorporation into higher (boron-rich) metal borides. Here, we demonstrate that when using five or more constituents, the higher mixing entropy will overcome these chemical limitations and form a …

Characterizations Of Bimetallic Silver-Copper Nanoparticles, Omar Lezcano

Undergraduate Honors Theses

The goal of this study was to characterize alloy nanoparticles with different bimetallic ratios of silver (Ag) and copper (Cu) by determining the composition and alloy structures. One specific objective was to determine how the composition affects the electrical properties of the nanoparticles in terms of electrical resistance and nanoparticle sintering. The desire for this study stems from the need to make conductive pastes for low-cost solar panel manufacturing. We performed experiments to develop the aqueous synthesis of core-shell bimetallic nanoparticles.

We investigated the room temperature sintering properties with the nanoparticles of varying compositions. The nanoparticles were characterized with several …