A5016582060- Radioactive element chemistry and processing
- Catalytic Processes in Materials Science
- Advanced Chemical Physics Studies
- Graphene research and applications
- Extraction and Separation Processes
- Surface and Thin Film Phenomena
- Chemical Synthesis and Characterization
- Catalysis and Oxidation Reactions
- Advanced Photocatalysis Techniques
- Electronic and Structural Properties of Oxides
- Advancements in Battery Materials
- Catalysts for Methane Reforming
- Quantum and electron transport phenomena
- Metal-Organic Frameworks: Synthesis and Applications
- ZnO doping and properties
- Lanthanide and Transition Metal Complexes
- Nanomaterials for catalytic reactions
- Magnetic properties of thin films
- Electrocatalysts for Energy Conversion
- Boron and Carbon Nanomaterials Research
- Semiconductor materials and devices
- Surface Chemistry and Catalysis
- Covalent Organic Framework Applications
- Chemical Thermodynamics and Molecular Structure
- Geochemistry and Elemental Analysis
University of South China
2016-2025
University of Wisconsin–Madison
2009-2021
Madison Group (United States)
2014-2021
Beijing Research Institute of Uranium Geology
2018
Aarhus University
2010
Brookhaven National Laboratory
2009
Lehigh University
2009
Technical University of Denmark
2009
National University of Singapore
2005-2008
Dalian University of Technology
2001-2002
We report that alkali ions (sodium or potassium) added in small amounts activate platinum adsorbed on alumina silica for the low-temperature water-gas shift (WGS) reaction (H(2)O + CO → H(2) CO(2)) used producing H(2). The ion-associated surface OH groups are activated by at low temperatures (~100°C) presence of atomically dispersed platinum. Both experimental evidence and density functional theory calculations suggest a partially oxidized Pt-alkali-O(x)(OH)(y) species is active site...
II-oxide and III-nitride semiconductors doped by nonmagnetic 2p light elements are investigated as potential dilute magnetic (DMS). Based on our first-principle calculations, nitrogen ZnO, carbon AlN predicted to be ferromagnetic. The ferromagnetism of such DMS materials can attributed a p-d exchange-like p-p coupling interaction which is derived from the similar symmetry wave function between impurity (p-like t_2) valence (p) states. We also propose co-doping mechanism, using beryllium...
Water-Assisted Proton Diffusion diffusion on metal oxide surfaces can play an important role in many catalytic processes. The presence of water is thought to accelerate proton diffusion. Merte et al. (p. 889 ) used high-speed, high-resolution scanning tunneling microscopy study iron oxide. On oxygen-terminated FeO monolayer films formed Pt, molecular accelerated Density function theory calculations implicated a H 3 O + transition state the process.
We improved the effectiveness of Pt monolayer electrocatalysts for oxygen-reduction reaction (ORR) using a novel approach to fine-tuning interaction with its support, exemplified by an annealed Pd(3)Fe(111) single-crystal alloy support having segregated Pd layer. Low-energy ion scattering and low-energy electron diffraction studies revealed that layer, same structure as (111), is formed on surface high-temperature-annealed Pd(3)Fe(111). This layer considerably more active than Pd(111); ORR...
Periodic, self-consistent, density functional theory (DFT) calculations are employed to study CO2 hydrogenation on Ni(111). with H adsorbed the surface and absorbed in subsurface is investigated systematically, respective microscopic reaction mechanisms elucidated. We show that Ni(111) formate intermediate more favorable than carboxyl intermediate. The goes through unidentate structure rapidly transforms into bidentate structure. Further from formic acid energetically difficult formation....
First-principles calculations based on spin density functional theory are performed to study the spin-resolved electronic properties of GaN doped with 6.25% Cu. The Cu dopants found polarized and calculated band structures suggest a 100% polarization conduction carriers. Cu-doped favors ferromagnetic ground state which can be explained in terms p-d hybridization mechanism, Curie temperature around 350K expected. These results that is promising dilute magnetic semiconductor free precipitates...
Within the area of surface science, one "holy grails" is to directly visualize a chemical reaction at atomic scale. Whereas this goal has been reached by high-resolution scanning tunneling microscopy (STM) in number cases for reactions occurring flat surfaces, such direct view often inhibited steps and interfaces. Here we have studied CO oxidation interface between ultrathin FeO islands Pt(111) support situ STM density functional theory (DFT) calculations. Time-lapsed imaging on inverse...
Contamination of 99TcO4–, a problematic radioactive anion in the nuclear fuel cycle, groundwater has been observed series legacy sites, representing notable radiation hazard and environmental concern. The development convenient, rapid, sensitive detection methods is therefore critical for radioactivity control remediation tasks. Traditional suffer from clear demerits either presence large interference coexisting species (e.g., counting methods) or requirement extensive instrumentation...
Ab initio calculations based on spin density functional theory were carried out to investigate Mg-doped AlN as a possible dilute magnetic semiconductor. It was found that both Al vacancy and substitutional Mg impurity in lead spin-polarized ground states. However, sufficient concentration may be difficult achieve under thermal equilibrium because of the high formation energy vacancy. On other hand, defect is fairly low authors’ predict ferromagnetic coupling among MgN4 tetrahedra. Based...
A combined experimental and computational study was carried out to investigate magnetic properties of NiO nanostructures. Remarkable size-dependent magnetism discovered. Uniform amorphous showed a dominated antiferromagnetic interaction an ordering temperature $3.5\phantom{\rule{0.3em}{0ex}}\mathrm{K}$. clusters (up $1\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$) tend be ferromagnetic with $35\phantom{\rule{0.3em}{0ex}}\mathrm{K}$, accompanied by high magnetization...
From an interplay between scanning tunneling microscopy, temperature programmed desorption, X-ray photoelectron spectroscopy, and density functional theory calculations we have studied low-temperature CO oxidation on Au/Ni(111) surface alloys Ni(111). We show that oxide is formed both the Ni(111) surfaces when oxygen dosed at 100 K, can be oxidized K of these in presence weakly bound oxygen. suggest rationalized by O(2)-saturated NiO(111) surfaces, main effect Au alloy to block formation...
Through an interplay between density functional theory and scanning tunneling microscopy, we investigated the mechanism of low-temperature CO oxidation on Ni(111) NiO(111) surfaces. We systematically examined different possible active sites. find that sub- full monolayers O chemisorbed surfaces play no significant role in oxidation. further show at perimeter islands cannot occur low temperatures. In contrast, suggest oxidized surfaces, i.e., NiO(111), can catalyze when is saturated by O2....
Monolayer thin FeO(111) films were grown on Pd(111) and oxidized by atomic oxygen (O). The stoichiometric studied in detail scanning tunneling microscopy (STM) density functional theory (DFT) calculations. Compared to the previously FeO(111)/Pt(111) system, small structural differences observed for FeO monolayer films. Upon O exposure, film reconstructs, leading formation of new O-rich structures incorporating increasing amounts additional atoms. At low exposures, STM images exhibit bright...
High-resolution scanning tunneling microscope (STM) images of moiré-structured FeO films on Pt(111) were obtained in a number different tip-dependent imaging modes. For the first time, STM are distinguished and interpreted unambiguously with help distinct oxygen-vacancy dislocation loops moiré structure. The experimental results compared electronic structure calculations within DFT+U scheme for realistic (√91 × √91)R5.2° unit cell supported as well from previous studies. We find that one...
Dissociation of molecular hydrogen is an important step in a wide variety chemical, biological, and physical processes. Due to the light mass hydrogen, it recognized that quantum effects are often its reactivity. However, understanding how impact reactivity still infancy. Here, we examine this issue using well-defined Pd/Cu(111) alloy allows activation deuterium molecules be examined at individual Pd atom surface sites over range temperatures. Experiments comparing uptake as function...
The interaction of iron with graphene/Pt(111) has been experimentally and theoretically investigated evidencing a splitting graphene π bands due to the hybridization Fe 3d states.
Atomic and molecular self-assembly are key phenomena that underpin many important technologies. Typically, thermally enabled diffusion allows a system to sample areas of configurational space, ordered assemblies evolve optimize interactions between species. Herein we describe in which the is quantum tunneling nature report H atoms on Cu(111) surface into complex arrays based local clustering followed by larger scale islanding these clusters. By scanning microscope tip-induced scrambling atom...