A5014585812- Catalytic Processes in Materials Science
- Advancements in Battery Materials
- Semiconductor materials and devices
- Advanced Battery Materials and Technologies
- Advanced Chemical Physics Studies
- Diamond and Carbon-based Materials Research
- Electrocatalysts for Energy Conversion
- Electronic and Structural Properties of Oxides
- GaN-based semiconductor devices and materials
- CO2 Reduction Techniques and Catalysts
- Advanced Photocatalysis Techniques
- Catalysis and Oxidation Reactions
- Metal and Thin Film Mechanics
- ZnO doping and properties
- Boron and Carbon Nanomaterials Research
- Graphene research and applications
- Quantum Dots Synthesis And Properties
- nanoparticles nucleation surface interactions
- Metal-Organic Frameworks: Synthesis and Applications
- Molecular Junctions and Nanostructures
- Advanced battery technologies research
- Carbon Nanotubes in Composites
- Magnetic and transport properties of perovskites and related materials
- Surface and Thin Film Phenomena
- Ga2O3 and related materials
Argonne National Laboratory
2016-2025
Alex's Lemonade Stand Foundation
2014-2021
Energy Storage Systems (United States)
2020
University of Chicago
2004-2012
Northwestern University
2010
Yale University
2010
University of Illinois Chicago
2007-2009
Paul Scherrer Institute
2009
Institute of Experimental Physics of the Slovak Academy of Sciences
2009
Center for Nanoscale Materials
2009
Conversion of carbon dioxide (CO2) into fuels is an attractive solution to many energy and environmental challenges. However, the chemical inertness CO2 renders electrochemical photochemical conversion processes inefficient. We report a transition metal dichalcogenide nanoarchitecture for catalytic monoxide (CO) in ionic liquid. found that tungsten diselenide nanoflakes show current density 18.95 milliamperes per square centimeter, CO faradaic efficiency 24%, formation turnover frequency...
The design of low-cost yet high-efficiency electrocatalysts for hydrogen evolution reaction (HER) and oxygen (OER) over a wide pH range is highly challenging. We now report hierarchical co-assembly interacting MoS2 Co9S8 nanosheets attached on Ni3S2 nanorod arrays which are supported nickel foam (NF). This tiered structure endows high performance toward HER OER very broad range. By adjusting the molar ratio Co:Mo precursors, we have created CoMoNiS-NF- xy composites ( x: y means ratios...
Ultrananocrystalline diamond (UNCD) films with up to 0.2% total nitrogen content were synthesized by a microwave plasma-enhanced chemical-vapor-deposition method using CH4(1%)/Ar gas mixture and 1%–20% added. The electrical conductivity of the nitrogen-doped UNCD increases five orders magnitude (up 143 Ω−1 cm−1) increasing content. Conductivity Hall measurements made as function film temperature down 4.2 K indicate that these have highest n-type carrier concentration demonstrated for...
Using the electron paramagnetic resonance technique, we have elucidated multiple roles of water and carbonates in overall photocatalytic reduction carbon dioxide to methane over titania nanoparticles. The formation H atoms (reduction product) •OH radicals (oxidation from water, CO3− radical anions carbonates, was detected CO2-saturated aqueous dispersion under UV illumination. Additionally, methoxyl, •OCH3, methyl, •CH3, were identified as reaction intermediates. two-electron, one-proton...
The activation of CO2 and its hydrogenation to methanol are much interest as a way utilize captured CO2. Here, we investigate the use size-selected Cu4 clusters supported on Al2O3 thin films for reduction in presence hydrogen. catalytic activity was measured under near-atmospheric reaction conditions with low partial pressure, oxidation state investigated by situ grazing incidence X-ray absorption spectroscopy. results indicate that most active low-pressure catalyst conversion CH3OH. Density...
Abstract Li 7 La 3 Zr 2 O 12 (LLZO) garnet‐based materials doped with Al, Nb, or Ta to stabilize the + ‐conductive cubic phase are a particularly promising class of solid electrolytes for all‐solid‐state lithium metal batteries. Understanding intrinsic reactivity between and relevant electrode is crucial developing high voltage solid‐state batteries long lifetimes. Using novel, surface science‐based approach characterize Li–solid electrolyte interface, it determined that, surprisingly, some...
Electrocatalytic conversion of carbon dioxide (CO2) into energy-rich fuels is considered to be the most efficient approach achieve a neutral cycle. Transition-metal dichalcogenides (TMDCs) have recently shown very promising catalytic performance for CO2 reduction reaction in an ionic liquid electrolyte. Here, we report that molybdenum disulfide (MoS2), member TMDCs, can significantly improved by using appropriate dopant. Our electrochemical results indicate 5% niobium (Nb)-doped vertically...
Perovskite oxides are an important class of oxygen evolution reaction (OER) catalysts in alkaline media, despite the elusive nature their active sites. Here, we demonstrate that origin OER activity a La1–xSrxCoO3 model perovskite arises from thin surface layer Co hydr(oxy)oxide (CoOxHy) interacts with trace-level Fe species present electrolyte, creating dynamically stable Generation is consequence process driven by A-site dissolution and O-vacancy creation. In turn, this imparts 10-fold...
Lithium–oxygen (Li–O2) batteries have been recognized as an emerging technology for energy storage systems owing to their high theoretical specific energy. One challenge is find electrolyte/cathode system that efficient, stable, and cost-effective. We present such a based on molybdenum disulfide (MoS2) nanoflakes combined with ionic liquid (IL) work together effective cocatalyst discharge charge in Li–O2 battery. Cyclic voltammetry results show superior catalytic performance this both oxygen...
Abstract Metal–organic frameworks (MOFs) are promising materials for electrocatalysis; however, lack of electrical conductivity in the majority existing MOFs limits their effective utilization field. Herein, an excellent catalytic activity a 2D copper (Cu)‐based conductive MOF, tetrahydroxyquinone (CuTHQ), is reported aqueous CO 2 reduction reaction (CO RR) at low overpotentials. It revealed that CuTHQ nanoflakes (NFs) with average lateral size 140 nm exhibit negligible overpotential 16 mV...
The corrosion of aluminum current collectors and the oxidation solvents at a relatively high potential have been widely investigated with an aim to stabilize electrochemical performance lithium-ion batteries using such components. behavior was revisited home-build high-precision measurement system, impact electrolyte components surface protection layer on foil systematically studied. results showed that triggered by solvent molecules, like ethylene carbonate, relative potential. organic...
Abstract The garnet‐type phase Li 7 La 3 Zr 2 O 12 (LLZO) attracts significant attention as an oxide solid electrolyte to enable safe and robust solid‐state batteries (SSBs) with potentially high energy density. However, while progress has been made in demonstrating compatibility metal, integrating LLZO into composite cathodes remains a challenge. current perspective focuses on the critical issues that need be addressed achieve ultimate goal of all‐solid‐state LLZO‐based battery delivers...
Ultrananocrystalline diamond (UNCD) films grown from hydrogen-poor plasmas have grain sizes of 3--10 nm, resulting in a large number boundaries. We report on density-functional-based tight-binding molecular-dynamics calculations high-energy high-angle twist (100) boundaries as model for the UNCD About one-half carbons boundary are threefold coordinated and responsible states introduced into band gap. Simulations were also performed N, Si, H impurities where substitution energies, optimized...
A thermodynamic model describing relative stability of different shapes for nanoparticles as a function their size was developed arbitrary crystalline solids and applied to group IV semiconductors. The makes use various surface, edge corner energies, takes into account surface tension. Approximations importance each term the were analyzed. predictions clean hydrogenated diamond are compared explicitly calculated density functional results. It is shown that nanocrystal morphology markedly...
We have examined the performance of Gaussian-3 (G3) theory and six related methods for calculation enthalpies formation n-alkanes up to 16 carbons isoalkanes 10 carbons. also accuracy B3LYP density functional n-alkanes. The G3 errors less than 2 kcal/mol compared experiment. There is a small accumulation error (0.04 per bond) that increases deviation with chain length. effects conformational averaging on are estimated be small, but in direction reduce error. branched alkanes 1 kcal/mol. Four...
Addition of water to 1-decyl-3-methylimidazolium bromide is shown result in its spontaneous self-organization and the concomitant formation a liquid-crystalline gel, thus providing simple means preparing supramolecular assembly comprising room-temperature ionic liquid.
Titanium dioxide nanoparticles are currently receiving a lot of attention due to their inherent suitability for advanced photochemical applications. Size, phase, and morphology the critical parameters determining performance in particular A thermodynamic model devised describe shape as function size has been used predict phase stability titanium nanoparticles, with given crossover between anatase rutile phases. Density functional calculations were accurately determine surface energies...
The interaction of catechol and water with titanium oxide nanoparticles was investigated using ab initio molecular orbital theory density functional theory. Hydrogen-terminated TiO2 clusters were used to model the surface anatase nanoparticles. calculations indicate that reacts a TiO defect site on form bidentate structure is favored over dissociative or adsorption (101) surface. at leads much larger red shift in excitation energy than basis ZINDO/S calculations. This consistent recent...
The potential of titanium dioxide nanoparticles for advanced photochemical applications has prompted a number studies to analyze the size, phase, and morphology dependent properties. Previously we have used thermodynamic model as function size shape predict phase stability nanoparticles, with particular attention given crossover between anatase rutile phases. This work now been extended in water, examine effects various adsorption configurations on equilibrium transition. Density functional...
A series of highly porous polymers with similar BET surface areas higher than 1000 m2 g−1 but tunable pore ranging from 0.7 nm to 0.9 were synthesized through facile ethynyl trimerization reaction demonstrate the property-hydrogen adsorption relationship.
Size-selected Cun catalysts (n = 3, 4, 20) were synthesized on Al2O3 thin films using mass-selected cluster deposition. A systematic study of size and support effects was carried out for CO2 hydrogenation at atmospheric pressure a combination in situ grazing incidence X-ray absorption spectroscopy, catalytic activity measurement, first-principles calculations. The methanol synthesis is found to strongly vary as function the size; Cu4/Al2O3 catalyst shows highest turnover rate CH3OH...
Binding configurations of CO2 and CO2− on perfect oxygen-deficient anatase (101) surfaces were explored using first-principles calculations both cluster periodic models. The solvent effect was taken into account via the polarizable continuum model. Analysis molecular orbitals, charge, spin density distributions used to help identify radical anion adsorbed surface. On defect-free surfaces, it is found bind as a bridging bidentate configuration with oxygens coordinating 5-fold Ti ions....