A5046284155- Catalytic Processes in Materials Science
- Electrocatalysts for Energy Conversion
- Catalysis and Oxidation Reactions
- Advanced Chemical Physics Studies
- Nanomaterials for catalytic reactions
- Catalysis for Biomass Conversion
- Machine Learning in Materials Science
- Multiferroics and related materials
- Ferroelectric and Piezoelectric Materials
- Surface Chemistry and Catalysis
- Electronic and Structural Properties of Oxides
- Catalysis and Hydrodesulfurization Studies
- Advanced Condensed Matter Physics
- Protein purification and stability
- Magnetic and transport properties of perovskites and related materials
- CO2 Reduction Techniques and Catalysts
- X-ray Diffraction in Crystallography
- Advanced battery technologies research
- Spectroscopy and Quantum Chemical Studies
- Acoustic Wave Resonator Technologies
- Modeling and Simulation Systems
- Hydrogen Storage and Materials
- nanoparticles nucleation surface interactions
- Elasticity and Material Modeling
- Advancements in Battery Materials
United States Military Academy
2021-2025
Pacific Northwest National Laboratory
2019-2023
Oak Ridge National Laboratory
2017-2020
Battelle
2019
The Ohio State University
2014-2018
Oak Ridge Associated Universities
2018
Tokyo Women's Medical University
2010-2011
Single-site copper-based catalysts have shown remarkable activity and selectivity for a variety of reactions. However, deactivation by sintering in high-temperature reducing environments remains challenge often limits their use due to irreversible structural changes the catalyst. Here, we report zeolite-based copper which oxide agglomerates formed after reaction can be repeatedly redispersed back single sites using an oxidative treatment air at 550 °C. Under different environments,...
Electrocatalytic hydrogenation is increasingly studied as an alternative to integrate the use of recycled carbon feedstocks with renewable energy sources. However, abundant empiric observations available have not been correlated fundamental properties substrates and catalysts. In this study, we investigated electrocatalytic a homologues series carboxylic acids, ketones, phenolics, aldehydes on variety metals (Pd, Rh, Ru, Cu, Ni, Zn, Co). We found that rates carbonyl reduction in correlate...
We present a perspective on the computational determination of entropy and its effects consequences heterogeneous catalysis. Special attention is paid to role anharmonicity (a result collective phenomena) deviations from standard harmonic oscillator approximations, which can fail provide reliable assessment entropy. To address these challenges, advanced methodologies are needed that explicitly account for thermodynamic drivers through appropriate statistical sampling reactive free-energy...
Single-atom catalysts are often reported to have catalytic properties that surpass those of nanoparticles, while a direct comparison sites common and different for both is lacking. Here we show single atoms Pt-group metals embedded into the surface Fe3O4 greatly enhanced interaction strength with CO2 compared surface. The strong adsorption on Rh corresponding low activation energies lead 2 orders magnitude higher conversion rates nanoparticles. This high activity stems from partially oxidic...
Enhanced sampling ab initio simulations enable to study chemical phenomena in catalytic systems including thermal effects & anharmonicity, collective dynamics describing enthalpic entropic contributions, which can significantly impact on reaction free energy landscapes.
Abstract Using the van der Waals density functional with C09 exchange (vdW-DF-C09), which has been applied to describing a wide range of dispersion-bound systems, we explore physical properties prototypical AB O 3 bulk ferroelectric oxides. Surprisingly, vdW-DF-C09 provides superior description experimental values for lattice constants, polarization and moduli, exhibiting similar accuracy modified Perdew-Burke-Erzenhoff was designed specifically solids (PBEsol). The relative performance is...
The high specific activity and cost-effectiveness of single-atom catalysts (SACs) hold great promise for numerous catalytic chemistries. In hydrogenation reactions, the mechanisms critical steps such as hydrogen activation spillover are far from understood. Here, we employ a combination scanning tunneling microscopy density functional theory to demonstrate that on model SAC comprised single Pd atoms Fe3O4(001), H2 dissociates heterolytically between surface oxygen. efficient allows...
Single-atom catalysis has been a topic of increasing interest due to the potential for improved selectivity, reactivity, and catalyst cost. However, single-atom catalysts are still difficult characterize under realistic reaction conditions, leading controversy regarding capabilities single atoms need model studies. Herein, we examine methanol on Pd supported Fe3O4(001) ultrahigh vacuum conditions. On Pd-free Fe3O4(001), small fraction is converted formaldehyde through methoxy intermediate at...
The hydrogenation of benzaldehyde to benzyl alcohol on carbon-supported metals in water, enabled by an external potential, is markedly promoted polarization the functional groups. presence polar co-adsorbates, such as substituted phenols, enhances rate aldehyde two effects, that is, polarizing carbonyl group and increasing probability forming a transition state for H addition. These effects enable route, which phenol acts conduit proton addition, with higher than direct transfer from...
Predicting the error in density functional theory (DFT) calculations due to choice of exchange–correlation (XC) is crucial success DFT, but currently, there are limited options estimate this a priori. This particularly important for high-throughput screening new materials. In work, structure and elastic properties binary ternary oxides computed using four XC functionals: LDA, PBE-GGA, PBEsol, vdW-DF with C09 exchange. To analyze systemic errors inherent each functional, we employed materials...
Rheological, electrochemical, and microstructural properties of graphene oxide suspensions as flowable electrodes for energy storage.
Thermo-responsive anionic terpolymer brushes with high selectivity for proteins were prepared though surface-initiated ATRP. Utilizing these brushes, pure lysozyme was successfully separated from egg-white. Thus, the thermo-responsive brush is an effective separation tool pharmaceutical and biotechnological industries that produce valuable proteins.
Boron oxide-based catalysts have been shown to be both active and selective for driving the oxidative dehydrogenation of propane (ODHP) without use metal promoters. However, this reaction occurs at temperatures where boron oxide melts, challenging experimental identification molecular structures within phase under conditions thus hindering understanding its sites mechanism(s). By combining density functional theory computations, ab initio dynamics simulations, in situ Raman characterization,...
Abstract The hydrogenation of benzaldehyde to benzyl alcohol on carbon‐supported metals in water, enabled by an external potential, is markedly promoted polarization the functional groups. presence polar co‐adsorbates, such as substituted phenols, enhances rate aldehyde two effects, that is, polarizing carbonyl group and increasing probability forming a transition state for H addition. These effects enable route, which phenol acts conduit proton addition, with higher than direct transfer...
Supported single-atom catalysts (SACs) have gained increasing attention for improved catalytic activity and selectivity industrially relevant reactions. In this study, we explore the hydrogenation of acetylene over single Pt, Ru, Rh, Pd, Ir atoms supported on Fe3O4(001) surface using density functional theory calculations. The thermodynamic profile H diffusion is significantly modified by type metal used, suggesting that spillover from atom dopant to favored will likely lead high coverages...
The slow kinetics of the oxygen evolution (OER) and reduction (ORR) reactions hamper development renewable energy storage conversion technologies. Transition-metal oxides (TMOs) are cost-effective replacements to conventional noble metal catalysts for driving these electrochemical systems. Strain is known greatly affect electronic structure TMO surfaces, leading significant changes in their electrocatalytic activities. In this study, we explore influence strain on OER ORR mechanisms...
Density functional theory was used to study CO adsorption on thin Pt metal films supported SrO- and TiO2-terminated SrTiO3(100) surfaces. Regardless of substrate-termination, significant enhancement in binding occurred the monolayer compared bulk Pt(100) surface. We also observed CO-coverage dependent shifting atoms, influenced by nature underlying oxide atoms. These oxide-induced effects become negligible after depositing more than 2 monolayers Pt. Evaluating electronic structures...
The van der Waals interaction is of foundational importance for a wide variety physical systems. In particular, forces lie at the heart potential device technologies that may be realized from functional organization layered two-dimensional (2D) nanomaterials. For intermediate to large-scale applications modeling, density functionals have become de facto choice first-principles calculations. vdW-DF family provided systematic approach this theoretically challenging problem. While much progress...
Ethanol is an important C2 platform molecule for producing value-added chemicals and distillate hydrocarbon fuels (e.g., jet diesel). Among these, catalytic upgrading of ethanol to butenes can generate valuable commodity 1-butene) provide C4 olefin intermediates that be further upgraded jet/diesel fuels. Two-dimensional (2D) zeolites offer hierarchical mesoporous structures, leading improved mass transport reduced diffusion length, which help address the coking challenges faced by conversion...
Strong interplay of fundamental order parameters in complex oxides are known to give rise exotic physical phenomena. The 4d transition metal oxide SrRhO3 has generated much interest, but advances have been hindered by difficulties preparing single crystalline phases. Here, we epitaxially stabilized high quality films and investigated their structural, electronic, magnetic properties. We determine that properties significantly differ from the paramagnetic metallic ground state governs bulk...