Surface electron-phonon energy exchange in small metallic particles

The splitting effect that is observed in microdiffraction pat-terns of small metallic particles in the size range 50-500 Å can be understood using the dynamical theory of electron diffraction for the case of a crystal containing a finite wedge. For the experimental data we refer to part I of this work in these proceedings.

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ESEM - A multipurpose surface Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100144607 ◽

1986 ◽

Vol 44 ◽

pp. 632-633 ◽

Cited By ~ 2

Author(s):

G.D. Danilatos

Keyword(s):

Electron Microscope ◽

Room Temperature ◽

Environmental Scanning ◽

Gas Composition ◽

Saturated Water Vapor ◽

Surface Electron ◽

Current State ◽

Saturated Water ◽

New Type ◽

Temperature And Pressure

Over recent years a new type of electron microscope - the environmental scanning electron microscope (ESEM) - has been developed for the examination of specimen surfaces in the presence of gases. A detailed series of reports on the system has appeared elsewhere. A review summary of the current state and potential of the system is presented here.The gas composition, temperature and pressure can be varied in the specimen chamber of the ESEM. With air, the pressure can be up to one atmosphere (about 1000 mbar). Environments with fully saturated water vapor only at room temperature (20-30 mbar) can be easily maintained whilst liquid water or other solutions, together with uncoated specimens, can be imaged routinely during various applications.

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SREM observation of the interaction between the in-situ deposited Pd small particles and MgO cleavage surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143523 ◽

1986 ◽

Vol 44 ◽

pp. 382-383

Author(s):

H.-J. Ou

Keyword(s):

Electron Microscopy ◽

Small Particle ◽

Small Particles ◽

Cleavage Surface ◽

Metallic Particles ◽

Microscopy Technique ◽

Ceramic Surfaces ◽

Reflection Electron Microscopy ◽

New Perspective

The understanding of the interactions between the small metallic particles and ceramic surfaces has been studied by many catalyst scientists. We had developed Scanning Reflection Electron Microscopy technique to study surface structure of MgO hulk cleaved surface and the interaction with the small particle of metals. Resolutions of 10Å has shown the periodic array of surface atomic steps on MgO. The SREM observation of the interaction between the metallic particles and the surface may provide a new perspective on such processes.

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Crystal structure-size relationship in ultrafine metallic particles

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100153300 ◽

1989 ◽

Vol 47 ◽

pp. 266-267

Author(s):

Jun Liu ◽

Mehmet Sarikaya ◽

Ilhan A. Aksay

Keyword(s):

Ultrafine Particles ◽

Carbon Film ◽

Lattice Defects ◽

Careful Examination ◽

Seeded Growth ◽

Gold Particles ◽

Metallic Particles ◽

Interfacial Structures ◽

Typical Particle ◽

Many Particles

Ultrafine particles usually have unique physical properties. This study illustrates how the lattice defects and interfacial structures between particles are related to the size of ultrafine crystalline gold particles.Colloidal gold particles were produced by reducing gold chloride with sodium citrate at 100°C. In this process, particle size can be controlled by changing the concentration of the reactant. TEM samples are prepared by transferring a small amount of solution onto a thin (5 nm) carbon film which is suspended on a copper grid. In this work, all experiments were performed with Philips 430T at 300 kV.With controlled seeded growth, particles of different sizes are produced, as shown in Figure 1. By a careful examination, it can be resolved that very small particles have lattice defects with complex interfaces. Some typical particle structures include multiple twins, resulting in a five-fold symmetry bicrystals, and highly disordered regions. Many particles are too complex to be described by simple models.

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