A5000143640- MXene and MAX Phase Materials
- Boron and Carbon Nanomaterials Research
- Advanced materials and composites
- Catalytic Processes in Materials Science
- Graphene research and applications
- Advanced ceramic materials synthesis
- Semiconductor materials and devices
- Gas Sensing Nanomaterials and Sensors
- Analytical Chemistry and Sensors
- Intermetallics and Advanced Alloy Properties
- Advanced Sensor and Energy Harvesting Materials
- Advanced Thermoelectric Materials and Devices
- 2D Materials and Applications
- Inorganic Chemistry and Materials
- Force Microscopy Techniques and Applications
- Spacecraft and Cryogenic Technologies
- Semiconductor materials and interfaces
- Nanowire Synthesis and Applications
- Hydrogen Storage and Materials
- Heat transfer and supercritical fluids
- Thermal properties of materials
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Carbon dioxide utilization in catalysis
- Catalysts for Methane Reforming
University of Central Florida
2016-2025
Orlando Health
2014
Center for NanoScience
2014
University of California, Los Angeles
2001-2007
Jet Propulsion Laboratory
2006
California NanoSystems Institute
2005
Southern California Earthquake Center
2003
University of Iowa
2003
Hope College
1998
University of Tennessee Health Science Center
1977
Abstract Thermoelectric power sources have consistently demonstrated their extraordinary reliability and longevity for deep space missions small unattended terrestrial systems. However, more efficient bulk materials practical devices are required to improve existing technology expand into large‐scale waste heat recovery applications. Research has long focused on complex compounds that best combine the electrical properties of degenerate semiconductors with low thermal conductivity glassy...
The storage of excess electrical generation, enabled through the electrolytic production hydrogen from water, would allow "load-shifting" power generation. This paves way for as an energy carrier to be further used a zero‑carbon fuel land, air, and sea transportation. However, challenges in transportation ultimately pose restrictions on its wider adaption along horizontal vertical vectors. paper investigates chemical carriers ranging small molecules such ammonia methane formic acid well...
Heterogeneous catalysis cannot be easily applied to solids such as cellulose. However, by mechanically grinding the correct catalyst and reactant, it is possible induce solid–solid or mechanocatalysis. This process allows a wide range of effectively utilized feedstock for commercially relevant compounds. Here we show set structural physical parameters important implementation catalysts in mechanocatalytic processes their application catalytic depolymerization Using best catalysts, which...
Using a mechanically driven Diels–Alder reaction we were able to characterize the chemical energetics of SPEX 8000M mixer/mill. Our results demonstrate that conditions produced by this type mill are similar those when performing same at 90 °C in solution. Discrete element models and situ temperature logging used analyse system. These indicate yields obtained using best correlated velocity media number non-zero force collisions.
This work presents the development of novel fluorinated graphene (FG)-based resistive humidity sensor. The sensor was fabricated by drop-casting FG suspension, as sensing material, on silver (Ag)-based interdigitated electrodes (IDEs). silver-based IDEs were screen printed a flexible polyimide substrate. suspension synthesized uniform dispersion in isopropyl alcohol (IPA), using ultra-sonication process. response sensors towards varying relative (RH) levels investigated, when RH varied from...
Catalytic hydrogenation is an important process used for the production of everything from foods to fuels. Current heterogeneous implementations this utilize metals as active species. Until recently, catalytic over a metal-free solid was unknown; implementation such system would eliminate health, environmental, and economic concerns associated with metal-based catalysts. Here, we report good rates yields catalyst well its unique mechanism. olefins achieved defect-laden h-BN (dh-BN) in...
The hydrogenation of waste gas carbon dioxide into value added molecules could reduce greenhouse emissions and our dependence on nonrenewable energy sources. Catalytic paths toward this goal typically involve high pressures low abundance transition metal catalysts. Here, we have found that vacancies induced in defect-laden hexagonal boron nitride (dh-BN) can effectively activate the CO2 molecule for hydrogenation. Subsequent to formic acid (HCOOH) methanol (CH3OH) occur through vacancy...
Abstract We present a density functional theory-based mechanistic understanding of CO 2 hydrogenation to value-added products on nitrogen-vacancy (V N ) defect in hexagonal boron nitride ( dh -BN). Activation occurs through back-donation the π * orbitals from frontier (defect state) h- BN sheet that are localized near nitrogen-vacancy. Subsequent methanol (CH 3 OH) and formic acid (HCOOH) proceed vacancy-facilitated co-adsorption hydrogen . More importantly, our reaction pathway analyses...
Mechanochemical approaches to chemical synthesis offer the promise of improved yields, new reaction pathways and greener syntheses. Scaling these syntheses is a crucial step toward realizing commercially viable process. Although much work has been performed on laboratory-scale investigations little done move industrially relevant scales. Moving reactions from shaker-type mills planetary-type scalable solutions can present challenge. We have investigated scalability through discrete element...
Chemical vapor deposition (CVD) precursor chemicals are held to some of the highest purity levels in industry. Many metal reagents form stable, unbreakable adducts with coordinating solvents that necessary for solvating highly polar reagents. These undesirable and must be removed prior usage. Herein we describe a mechanochemical approach synthesis bis(n-propyltetramethylcyclopentadienyl)strontium eliminates use strongly solvents. This method overcomes solubility problems two without...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTConstruction of a Polyaniline Nanofiber Gas SensorRichard Blair , Heather Shepherd Tanya Faltens Philip C. Haussmann Richard B. Kaner Sarah H. Tolbert Jiaxing Huang Shabnam Virji and Bruce Weiller View Author Information Department Chemistry, University Central Florida, Orlando, FL 32816-2366 Chemistry Biochemistry California NanoSystems Institute, California–Los Angeles, Los CA 90095-1569 Materials Science Engineering, Northwestern University,...
The addition of lithium amide (LiNH2) and ammonium chloride (NH4Cl) to metathesis (exchange) reactions between gallium triiodide (GaI3) nitride (Li3N) produces crystalline (GaN) in seconds at ambient pressure. A specially designed rate cell incorporating multiple thermocouples enables both the reaction velocity temperatures be measured. Without additives, GaI3/Li3N propagates >100 cm/s with a temperature above 1300 K, which exceeds 1150 K decomposition GaN. By adding an optimal ratio LiNH2...
High-energy ball milling has been successfully employed to produce alkaline earth carbides from the elements. In particular, CaC(2) yields of up 98% can be realized in as little 12 h. Similarly, Mg (39% yield), Sr (87% and Ba (82% yield) have prepared. An intermediate synthesis is newly discovered gold-colored Ca-graphite intercalation compound CaC(6). also go through initial phases (SrC(6) BaC(6)) before ultimately producing carbides. The magnesium product consisted Mg(2)C(3) with no MgC(2)...
A novel and flexible capacitive humidity sensor was successfully fabricated using additive screen printing process. silver (Ag) ink deposited on the polyimide substrate in interdigitated finger pattern sensitive fluorinated graphene drop casted Ag-based electrodes. The response of towards varying relative (RH) levels ranging from 20% RH to 70% investigated. An overall capacitance change 311.5% observed for at an operating frequency voltage 1 kHz V, respectively. effect sensor's performance...
Nanostructured silicon has recently been identified as an attractive material for a wide variety of uses from energy conversion and storage to biological applications. Here we present new, rapid method producing high-purity, nanostructured, unfunctionalized via solid-state metathesis (SSM) in matter seconds. The forms double displacement reaction between tetraiodide alkaline earth silicide precursor. products are characterized using powder X-ray diffraction, scanning electron microscopy...
AlMgB14 ceramics were reported as high-hardness materials over a decade ago. While different synthesis routes for processing of in the past, however are still not optimised and present significant challenge to manufacturers. In this work six explored powder. The synthesised compositions characterised by XRD, where weight fractions each phase calculated Rietveld refinement. bulk sintered using powder with highest yield (93.2%) spark plasma sintering at 1315°C 50 MPa. Both composition...
Nitrides, such as magnesium silicon nitride, hold promise for applications requiring materials with high thermal conductivity. The synthesis of the ternary nitride MgSiN2 is accomplished using SiO2 and Mg3N2 reactants in a solid-state metathesis (exchange) reaction. This self-propagating reaction readily initiated when flame temperature ≥1100 °C brought into contact pressed SiO2/Mg3N2 pellet. By ≥1 M excess, X-ray-pure can be produced. With lower ratios, elemental forms an impurity....