A5036960935- Catalytic Processes in Materials Science
- Advanced Chemical Physics Studies
- Electrocatalysts for Energy Conversion
- Copper-based nanomaterials and applications
- Machine Learning in Materials Science
- Electrochemical Analysis and Applications
- CO2 Reduction Techniques and Catalysts
- Molecular Junctions and Nanostructures
- ZnO doping and properties
- Advancements in Battery Materials
- Nanomaterials for catalytic reactions
- Ammonia Synthesis and Nitrogen Reduction
- Advanced Photocatalysis Techniques
- Nanocluster Synthesis and Applications
- Electronic and Structural Properties of Oxides
- Quantum Dots Synthesis And Properties
- Advanced Battery Technologies Research
- Ionic liquids properties and applications
- Catalysis and Oxidation Reactions
- Advanced Battery Materials and Technologies
- Carbon dioxide utilization in catalysis
- Advanced battery technologies research
- Hydrogen Storage and Materials
- Surface Chemistry and Catalysis
- Analytical Chemistry and Sensors
Interface (United States)
2021-2025
SLAC National Accelerator Laboratory
2021-2025
Stanford University
2021-2025
Stockholm University
2018-2025
AlbaNova
2018-2025
Ames Research Center
2024-2025
Intel (United States)
2024
KTH Royal Institute of Technology
2013-2019
Stockholm Environment Institute
2016-2019
New York University
2012
Efficient oxygen evolution reaction (OER) electrocatalysts are pivotal for sustainable fuel production, where the Ni-Fe oxyhydroxide (OOH) is among most active catalysts alkaline OER. Electrolyte alkali metal cations have been shown to modify activity and intermediates, however, exact mechanism at question due unexplained deviations from cation size trend. Our X-ray absorption spectroelectrochemical results show that bigger shift Ni2+/(3+δ)+ redox peak OER lower potentials (however, with...
The active chemical state of zinc (Zn) in a zinc-copper (Zn-Cu) catalyst during carbon dioxide/carbon monoxide (CO2/CO) hydrogenation has been debated to be Zn oxide (ZnO) nanoparticles, metallic Zn, or Zn-Cu surface alloy. We used x-ray photoelectron spectroscopy at 180 500 millibar probe the nature and reaction intermediates CO2/CO over Zn/ZnO/Cu(211), where temperature is sufficiently high for rapidly turn over, thus creating an almost adsorbate-free surface. Tuning grazing incidence...
Abstract The electrochemical conversion of carbon di-/monoxide into commodity chemicals paves a way towards sustainable society but it also presents one the great challenges in catalysis. Herein, we present trends selectivity specific dicarbon oxygenate/hydrocarbon products from monoxide reduction on transition metal catalysts, with special focus copper. We unveil distinctive role electrolyte pH tuning selectivity. understanding is based density functional theory calculated energetics and...
Crystalline surfaces of gold are chemically inert, whereas nanoparticles excellent catalysts for many reactions. The catalytic properties nanostructured have been connected to increased binding affinities reactant molecules low-coordinated Au atoms. Here we show that the high reactivity at these sites is a consequence formation σ-holes, i.e., maxima in surface electrostatic potential (VS,max), due overlap mainly valence s-orbitals when forming bonding σ-orbitals. σ-holes Lewis bases, and...
Using local DFT-based probes for electrostatic as well charge transfer/polarization interactions, we are able to characterize Lewis basic and acidic sites on copper, silver gold nanoparticles. The predictions obtained using the DFT-probes compared interaction energies of electron donating (CO, H2O, NH3 H2S) accepting (BH3, BF3, HCl [H-down] Na+) compounds. include attachment energy [E(r)], average ionization [Ī(r)], potential [V(r)] evaluated isodensity surfaces located at distances...
Roughened copper electrodes, including those derived from cuprous oxide, have long been known to exhibit an enhanced Faradaic efficiency C2+ products during CO2 electroreduction. However, the source of this enhancement has not rationalized mechanistically. In work, we present a theoretical study roughened electrodes phosphide, nitride, and sulfide. We utilize carefully benchmarked effective medium theory potential develop geometric models on unprecedented scale. Using density functional with...
The electrochemical nitrate reduction reaction (NO3RR) on titanium introduces significant surface reconstruction and forms hydride (TiHx, 0 < x ≤ 2). With ex situ grazing-incidence X-ray diffraction (GIXRD) absorption spectroscopy (XAS), we demonstrated near-surface TiH2 enrichment with increasing NO3RR applied potential duration. This quantitative relationship facilitated treatment of Ti to form TiH2/Ti electrodes for use in NO3RR, thereby decoupling formation from performance. A wide range...
Molecular knots are often prepared using metal helicates to cross the strands. We found that coordinatively mismatching oligodentate ligands and ions provides a more effective way synthesize larger Vernier templating. Strands composed of different numbers tridentate 2,6-pyridinedicarboxamide groups fold around nine-coordinate lanthanide (III) generate strand-entangled complexes with lowest common multiple coordination sites for ligand strands ions. Ring-closing olefin metathesis then...
The study of multimetallic alloys and the multitude possible surface compositions have sparked a tremendous interest in engineering low-cost materials with high activity selectivity heterogeneous catalysis. Multimetallic systems provide complementary functionalities an unprecedented tunability when designing catalyst formulations. However, due to their immense structural compositional complexity, investigation identification optimal is tedious time-consuming process, both experimentally...
Abstract The current status of the molecular surface property approach (MSPA) and its application for analysis prediction intermolecular interactions, including chemical reactivity, are reviewed. MSPA allows identification characterization all potential interaction sites a molecule or nanoparticle by computation one more properties on an electronic isodensity surface. A wide range interactions can be analyzed three properties, which well‐defined within Kohn–Sham density functional theory....
Electrochemical reactions depend on the electrochemical interface between electrode surfaces and electrolytes. To control advance there is a need to develop realistic simulation models of understand from an atomistic point-of-view. Here we present method for obtaining thermodynamic structures, procedure use derive specific coverages obtain ab initio simulated cyclic voltammograms. As case study, applied in matrix study three Cu facets different The results have been validated by direct...
Accurate theoretical simulation of electrochemical activation barriers is key to understanding electrocatalysis and guides the design more efficient catalysts. Providing a detailed picture proton transfer processes encounters several challenges: constant potential requirement during charge transfer, different time scales involved in processes, thermal fluctuation solvent. Hence, it prohibitively expensive computationally apply density functional theory (DFT) calculations modeling...
Abstract The chemisorption energy is an integral aspect of surface chemistry, central to numerous fields such as catalysis, corrosion, and nanotechnology. Electronic-structure-based methods the Newns-Anderson model are therefore great importance in guiding engineering material surfaces with optimal properties. However, existing inadequate for interpreting complex, multi-metallic systems. Herein, we introduce a physics-based alloyed transition metal employing primarily d -band properties that...
A new local property, the electron attachment energy [E(r)], is introduced and demonstrated to be a useful guide predict intermolecular interactions chemical reactivity. The E(r) analogous average ionization but indicates susceptibility toward with nucleophiles rather than electrophiles. functional form motivated based on Janak's theorem piecewise linear dependence of addition atomic molecular systems. Within generalized Kohn-Sham method (GKS-DFT), only virtual orbitals negative eigenvalues...
Despite the industrial importance of copper oxides, nature (100) surface Cu2O has remained poorly understood. The previously been subject to several theoretical and experimental studies, but until now not investigated by atomically resolved microscopy or high-resolution photoelectron spectroscopy. Here we determine atomic structure electronic properties Cu2O(100) a combination multiple techniques simulations within framework density functional theory (DFT). Low-energy electron diffraction...
A local multiorbital electrophilicity descriptor, the electron attachment energy [E(r)], is used to study nucleophilic aromatic substitution reactions of SNAr and VNS (vicarious substitution). E(r) considers all virtual orbitals below free limit determined on molecular isodensity contour 0.004 atomic units. Good (R2 = 0.83) excellent 0.98) correlations are found between descriptor values experimental reactivity data for six series deficient arenes. These include homo- heteroarenes, rings...
Supported metal nanoparticles are essential components of high-performing catalysts, and their structures intensely researched. In comparison, nanoparticle spatial distribution in powder catalysts is conventionally not quantified, the influence this collective property on catalyst performance remains poorly investigated. Here, we demonstrate a general colloidal self-assembly method to control uniformity common industrial supports. We quantify distributions nanoscale using image statistics...
Bimetallic catalysts with optimal CO and C affinity for electrochemical reduction of 2 (eCO R) to high-value multi-carbon chemicals are identified by screening transition p-block metals complementary strong weak binding energy.
The potential energy surfaces in gas phase and aqueous solution for the nitration of benzene, chlorobenzene, phenol have been elucidated with density functional theory at M06-2X/6-311G(d,p) level combined polarizable continuum solvent model (PCM). Three reaction intermediates identified along both surfaces: unoriented π-complex (I), oriented complex (II), σ-complex (III). In order to obtain quantitatively reliable results positional selectivity modeling expulsion proton, it is crucial take...
Challenges in improving catalysts for electrochemical CO2 reduction require a clear understanding of the reaction mechanisms that lead to products higher value. In this work, we use density functional theory (DFT) determine most competitive coupling leading C3 on Cu(100) and Cu(511). We exhaustively consider surface pathways between CO* different C2 intermediates. On Cu(100), with acetaldehyde was identified as notable step product formation. Cu(511), local field stabilizations enable an...
Enhancing the power of lithium-ion batteries necessitates understanding molecular processes governing Li+ ion transfer across electrode-electrolyte interface. Here, employing enhanced sampling dynamics simulations, we investigated driving force and thermodynamic barrier adsorption onto Li0.5CoO2 (104) in LiClO4-, LiPF6-, LiTFSI-based EC/EMC (3:7) electrolytes. The weaker cation-anion pairing LiTFSI compared to LiClO4 was found enhance for from -0.48 eV -1.26 an interface with zero cation...