A5101764147- Electrocatalysts for Energy Conversion
- Catalytic Processes in Materials Science
- nanoparticles nucleation surface interactions
- Fuel Cells and Related Materials
- Surface and Thin Film Phenomena
- Nanocluster Synthesis and Applications
- Molecular Junctions and Nanostructures
- Gas Sensing Nanomaterials and Sensors
- Natural product bioactivities and synthesis
- Gold and Silver Nanoparticles Synthesis and Applications
- Graphene research and applications
- Electrochemical Analysis and Applications
- Surface Chemistry and Catalysis
- Force Microscopy Techniques and Applications
- Advanced Chemical Physics Studies
- Advanced Materials Characterization Techniques
- Advanced Memory and Neural Computing
- Ga2O3 and related materials
- Transition Metal Oxide Nanomaterials
- Analytical Chemistry and Sensors
- Advanced battery technologies research
- Phytochemical Studies and Bioactivities
- Ginseng Biological Effects and Applications
- Plant biochemistry and biosynthesis
- Nanomaterials for catalytic reactions
Shaanxi Normal University
2015-2024
Beijing Normal University
2024
Lanzhou University of Technology
2024
China XD Group (China)
2020
Henan Agricultural University
2020
Peking University
2020
Nankai University
2006-2017
Collaborative Innovation Center of Chemical Science and Engineering Tianjin
2017
Advanced Energy Materials (United States)
2017
University of Birmingham
2007-2016
Three types of bimetallic AgAu nanoparticles, with mean size 4-5 nm, Ag(core)Au(shell), Au(core)Ag(shell) and alloyed AgAu, have been synthesized using an inverse micelle method. To image these small quantitative high angle annular dark field imaging scanning transmission electron microscopy was successfully applied. Our results show that good control nanoparticle dispersion composition modulation achieved. Optical properties the nanoparticles are correlated direct internal structure...
Synthesis of bimetallic clusters is a topic accelerated interest; their physical and chemical properties are greatly dependent on composition, size, structure. The cluster beam technique widely used for preparation clusters. However, creating with well-controlled structure, especially larger (>100 atoms), still big challenge. Here we demonstrate that not only size composition but also the structure can be controlled by tuning aggregation parameters.
We experimentally demonstrated a 251st harmonic ultrashort pulse laser based on Cu<sub>2</sub>O nanocubes as saturable absorber.
We introduce a new type of cluster beam source based on the assembly (metal) clusters within condensed (rare gas) matrix. The "Matrix Assembly Cluster Source" employs an ion to enhance collisions between metal atoms in matrix and sputter out form beam. demonstrate formation deposition gold silver nanoclusters with mean size tunable from few thousand atoms. flux is equivalent current nanoAmp regime but potentially scalable milliAmps, which would open up number interesting experiments applications.
Mass spectrometry of supported, monolayer-protected, nominally Au(38) (MP-Au(38)) clusters is performed via quantitative High Angle Annular Dark Field-Scanning Transmission Electron Microscopy (HAADF-STEM) using size-selected Au(N) (N = 25, 38, 55) as mass standards. With the intensity due to (presumed) 24 hexanethiolate ligands taken into account, are found contain 38 +/- 2 Au atoms. The method may also be used determine degree aggregation deposited nanoparticles.
The generation of beams atomic clusters in the gas phase and their subsequent deposition (in vacuum) onto suitable catalyst supports, possibly after an intermediate mass filtering step, represents a new attractive approach for preparation model particles. Compared with colloidal route to production pre-formed catalytic nanoparticles, nanocluster beam offers several advantages: produced have no ligands, size can be selected arbitrarily high precision by filter, metal particles containing...
Abstract The widespread use of low-temperature polymer electrolyte membrane fuel cells for clean energy source require significant reductions in the amount expensive electrocatalyst Pt oxygen reduction reaction (ORR). based binary alloys are promising materials more active and stable electrocatalysts. In this paper, we studied Pt–Ce nanoalloy, which was prepared by hydrogen techniques as ORR Among all PtCe alloy catalysts, PtCe/C-800 ℃ shows superior activity, stability durability compared...
Abstract Structure‐controlled Pt‐based nanocrystals have the great potential to provide a flexible strategy for improving catalysis of oxygen reduction reaction (ORR). Here, new synthetic approach is developed tune 3D structure alloys, and switch which produces solid PtCu octahedral stars (OSs) produce nested skeleton cubes (NSCs) by simple addition Ni(acac) 2 . In particular, Ni 2+ ‐guided anisotropic growth observed generate in NSCs. , though absent from nanoalloys, not only endows faster...
Three new dammarane glycosides (1—3), together with five known compounds, gypenoside LXIX (4), gylongiposide I (5), XLVIII (6), allantion (7) and vitexin (8) were isolated from the MeOH extract of aerial parts Gynostemma pentaphyllum. Compounds 5, 7, 8 this plant for first time. Their structures elucidated by 1D 2D NMR spectra interpretation as well chemical degradation.
We report the size-dependent propagation of gold nanoclusters through few-layer graphene (FLG). employ aberration-corrected scanning transmission electron microscopy (STEM) to track fate Au55 and Au923 clusters that have been deposited, independently isoenergetically, onto suspended FLG films using cluster beam deposition. demonstrate penetrate FLG, whereas monodisperse reside at surface. Our approach offers a route controlled incorporation dopant nanoparticles generation nanoscale defects...
Nine new dammarane saponins, 1-9, were isolated from the MeOH extract of aerial part Gynostemma pentaphyllum, an edible plant Cucurbitaceae family, that grows wildly in China. Their structures elucidated by 1D- and 2D-NMR analysis, as well chemical degradation. Aglycons 21,24-cyclopentyldammar-25-ene 6 7, 21,24-cyclopentyldammarane 8 9, novel. Compounds 1, 4, showed moderate antitumor activities against stomach cancer cells SGC-7901 liver BEL-7402.
The stability of model catalysts based on size-selected Pd clusters supported graphite surfaces has been explored under realistic conditions for catalytic oxidation methane at mild temperatures. experimental results show that aggregated films nanoparticles are highly unstable, but pinned to the surface in submonolayer coverage regime much more stable against sintering. degree sintering clusters, which does occur, proceeds by release from their pinning sites. suppression depends cluster...
Bimetallic clusters can display new characteristics that cannot be obtained by varying either the size of pure metallic systems or composition bulk bimetals. We have demonstrated both copper (Cu)-rich core/gold (Au)-rich shell and Au-rich/Cu-rich prepared using radio frequency (RF) magnetron-sputtering gas phase cluster beam synthesis method with subsequent mass selection. Here we present an aberration-corrected scanning transmission electron microscopy (STEM) study ageing deposited...