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Dong Wang

Bio: Dong Wang is an academic researcher from Chinese Academy of Sciences. The author has contributed to research in topics: Scanning tunneling microscope & Medicine. The author has an hindex of 49, co-authored 491 publications receiving 9970 citations. Previous affiliations of Dong Wang include University of Science and Technology of China & Shanghai University.


Papers
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Journal ArticleDOI
Dong Wang1, Qing-Min Xu1, Li-Jun Wan1, Chen Wang1, Chunli Bai1 
01 Jun 2002-Langmuir
TL;DR: In this paper, the authors used cyclic voltammetry and electrochemical scanning tunneling microscopy (STM) imaging to reveal the details of the adlayer structures and internal structure of individual molecules.
Abstract: Adsorption of pyridine, pyrazine, and triazine molecules on a Cu(111) electrode surface was studied in aqueous solution by using cyclic voltammetry and electrochemical scanning tunneling microscopy (STM). High-resolution STM imaging reveals the details of the adlayer structures and internal structure of individual molecules. The molecules are found to form long-range well-ordered adlayers. The same (3 × 3) structures with a coverage of 0.11 are observed on the three adlayers. All three molecules adopt flat-lying orientation in the double-layer potential region, although the adsorption geometries are different. π electrons are believed to be important in stabilizing the molecules in flat-lying orientation. Three structural models are proposed for the three adlayers.

21 citations

Journal ArticleDOI
TL;DR: In this article, the feasibility of operating the Shanghai X-ray free-electron laser test facility with a single stage echo-enabled harmonic generation (EEHG) setup was studied.
Abstract: The echo-enabled harmonic generation (EEHG) scheme holds promising prospects for efficiently generating intense coherent radiation at very high harmonics of the initial seed laser. In this paper, we study the feasibility of operating the Shanghai X-ray free-electron laser test facility with a single stage EEHG setup. With a combination of existing numerical codes, start-to-end simulations considering various three-dimensional effects have been carried out to show the possible performance of the EEHG FEL. Simulation results demonstrate that a single stage EEHG can generate high power soft X-ray radiation pulses with narrow bandwidth directly from UV seed lasers. With the help of the harmonic lasing technique or upgraded linac, we also show the possibility of generating coherent soft X-ray radiation in the “water window” with a single stage EEHG.

21 citations

Journal ArticleDOI
Tao Zhang1, Zhen Qiao1, Yan Wang1, Neng-Jun Zhong1, Li Liu1, Dong Wang1, Yi Chen1 
TL;DR: An enantioselective direct α-alkylation of 2-oxindoles with Michler's hydrol via an S(N)1-type pathway in the non-covalent activation mode using the bis-cinchona alkaloid and Brønsted acid as a co-catalyst was developed and good to high yields and enantiOSElectivities were obtained.

21 citations

Journal ArticleDOI
01 Dec 2016
TL;DR: In this paper, an in-situ electrochemical scanning tunneling microscopy (ECSTM) investigation of the 5,10,15,20-tetraphenyl-21H,23H-porphine cobalt(II) (CoTPP)-catalyzed oxygen reduction reaction (ORR) was performed.
Abstract: We report an in situ electrochemical scanning tunneling microscopy (ECSTM) investigation of the 5,10,15,20-tetraphenyl-21H,23H-porphine cobalt(II) (CoTPP)-catalyzed oxygen reduction reaction (ORR). A highly ordered CoTPP adlayer is revealed on the Au(111) electrode. High-contrast adsorbed species are monitored in CoTPP adlayer in electrolyte containing oxygen, and are attributed to the formation of CoTPP–O2 complexes. In situ STM results reveal the sharp contrast changes upon switching the substrate potential to trigger the ORR. The results benefit the understanding of the catalytic role of metal porphyrins (MPs) in the ORR, which is important for the design of MP-based catalysts.

21 citations

Journal ArticleDOI
TL;DR: A novel self-modulation method for enhancing laser-induced energy modulation is reported, thereby significantly reducing the requirement of an external laser system and marking a major step toward a high-repetition-rate, fully coherent x-ray FEL.
Abstract: The spectroscopic techniques for time-resolved fine analysis of matter require coherent x-ray radiation with femtosecond duration and high average brightness. Seeded free-electron lasers (FELs), which use the frequency up-conversion of an external seed laser to improve temporal coherence, are ideal for providing fully coherent soft x-ray pulses. However, it is difficult to operate seeded FELs at a high repetition rate due to the limitations of present state-of-the-art laser systems. Here, we report a novel self-modulation method for enhancing laser-induced energy modulation, thereby significantly reducing the requirement of an external laser system. Driven by this scheme, we experimentally realize high harmonic generation in a seeded FEL using an unprecedentedly small external laser-induced energy modulation. An electron beam with a laser-induced energy modulation as small as 1.8 times the slice energy spread is used for lasing at the seventh harmonic of a 266-nm seed laser in a single-stage high-gain harmonic generation (HGHG) setup and the 30th harmonic of the seed laser in a two-stage HGHG setup. The results mark a major step toward a high-repetition-rate, fully coherent x-ray FEL.

20 citations


Cited by
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Journal ArticleDOI
TL;DR: Extracellular vesicles are now considered as an additional mechanism for intercellular communication, allowing cells to exchange proteins, lipids and genetic material.
Abstract: Extracellular vesicles are a heterogeneous group of cell-derived membranous structures comprising exosomes and microvesicles, which originate from the endosomal system or which are shed from the plasma membrane, respectively They are present in biological fluids and are involved in multiple physiological and pathological processes Extracellular vesicles are now considered as an additional mechanism for intercellular communication, allowing cells to exchange proteins, lipids and genetic material Knowledge of the cellular processes that govern extracellular vesicle biology is essential to shed light on the physiological and pathological functions of these vesicles as well as on clinical applications involving their use and/or analysis However, in this expanding field, much remains unknown regarding the origin, biogenesis, secretion, targeting and fate of these vesicles

4,241 citations

Journal ArticleDOI
TL;DR: This review presents a comprehensive overview of the lithium metal anode and its dendritic lithium growth, summarizing the theoretical and experimental achievements and endeavors to realize the practical applications of lithium metal batteries.
Abstract: The lithium metal battery is strongly considered to be one of the most promising candidates for high-energy-density energy storage devices in our modern and technology-based society. However, uncontrollable lithium dendrite growth induces poor cycling efficiency and severe safety concerns, dragging lithium metal batteries out of practical applications. This review presents a comprehensive overview of the lithium metal anode and its dendritic lithium growth. First, the working principles and technical challenges of a lithium metal anode are underscored. Specific attention is paid to the mechanistic understandings and quantitative models for solid electrolyte interphase (SEI) formation, lithium dendrite nucleation, and growth. On the basis of previous theoretical understanding and analysis, recently proposed strategies to suppress dendrite growth of lithium metal anode and some other metal anodes are reviewed. A section dedicated to the potential of full-cell lithium metal batteries for practical applicatio...

3,812 citations

Journal ArticleDOI
TL;DR: The unique advances on ultrathin 2D nanomaterials are introduced, followed by the description of their composition and crystal structures, and the assortments of their synthetic methods are summarized.
Abstract: Since the discovery of mechanically exfoliated graphene in 2004, research on ultrathin two-dimensional (2D) nanomaterials has grown exponentially in the fields of condensed matter physics, material science, chemistry, and nanotechnology. Highlighting their compelling physical, chemical, electronic, and optical properties, as well as their various potential applications, in this Review, we summarize the state-of-art progress on the ultrathin 2D nanomaterials with a particular emphasis on their recent advances. First, we introduce the unique advances on ultrathin 2D nanomaterials, followed by the description of their composition and crystal structures. The assortments of their synthetic methods are then summarized, including insights on their advantages and limitations, alongside some recommendations on suitable characterization techniques. We also discuss in detail the utilization of these ultrathin 2D nanomaterials for wide ranges of potential applications among the electronics/optoelectronics, electrocat...

3,628 citations

Journal ArticleDOI
22 Jan 2016-Science
TL;DR: In this paper, the oxygen reduction reaction (ORR) active site was characterized by using newly designed graphite (highly oriented pyrolitic graphite) model catalysts with well-defined π conjugation and well-controlled doping of N species.
Abstract: Nitrogen (N)-doped carbon materials exhibit high electrocatalytic activity for the oxygen reduction reaction (ORR), which is essential for several renewable energy systems. However, the ORR active site (or sites) is unclear, which retards further developments of high-performance catalysts. Here, we characterized the ORR active site by using newly designed graphite (highly oriented pyrolitic graphite) model catalysts with well-defined π conjugation and well-controlled doping of N species. The ORR active site is created by pyridinic N. Carbon dioxide adsorption experiments indicated that pyridinic N also creates Lewis basic sites. The specific activities per pyridinic N in the HOPG model catalysts are comparable with those of N-doped graphene powder catalysts. Thus, the ORR active sites in N-doped carbon materials are carbon atoms with Lewis basicity next to pyridinic N.

3,201 citations

Journal ArticleDOI
TL;DR: This comprehensive Review focuses on the low- and non-platinum electrocatalysts including advanced platinum alloys, core-shell structures, palladium-based catalysts, metal oxides and chalcogenides, carbon-based non-noble metal catalysts and metal-free catalysts.
Abstract: The recent advances in electrocatalysis for oxygen reduction reaction (ORR) for proton exchange membrane fuel cells (PEMFCs) are thoroughly reviewed. This comprehensive Review focuses on the low- and non-platinum electrocatalysts including advanced platinum alloys, core–shell structures, palladium-based catalysts, metal oxides and chalcogenides, carbon-based non-noble metal catalysts, and metal-free catalysts. The recent development of ORR electrocatalysts with novel structures and compositions is highlighted. The understandings of the correlation between the activity and the shape, size, composition, and synthesis method are summarized. For the carbon-based materials, their performance and stability in fuel cells and comparisons with those of platinum are documented. The research directions as well as perspectives on the further development of more active and less expensive electrocatalysts are provided.

2,964 citations