The Contribution of Carbon Supports on the Activity of Pt for Glycerol Electrooxidation: the Importance of Investigating the Derivative Voltammogram and Arrhenius Plots

Under a variety of electron microscope specimen preparation techniques different forms of chromatin appearance can be distinguished: beads-on-a-string, a 100 Å nucleofilament, a 250 Å fiber and a compact 300 to 500 Å fiber.Using a standardized specimen preparation technique we wanted to find out whether there is any relation between these different forms of chromatin or not. We show that with increasing ionic strength a chromatin fiber consisting of a row of nucleo- somes progressively folds up into a solenoid-like structure with a diameter of about 300 Å.For the preparation of chromatin for electron microscopy the avoidance of stretching artifacts during adsorption to the carbon supports is of utmost importance. The samples are fixed with 0.1% glutaraldehyde at 4°C for at least 12 hrs. The material was usually examined between 24 and 48 hrs after the onset of fixation.

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Comparison of TEM and STM observations of small silver clusters on different carbon supports

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017445x ◽

1990 ◽

Vol 48 (4) ◽

pp. 264-265

Author(s):

Bernd Tesche ◽

Tobias Schilling

Keyword(s):

Vibration Isolation ◽

Pyrolytic Graphite ◽

Carbon Film ◽

Silver Clusters ◽

Carbon Supports ◽

Stacking Order ◽

System P ◽

High Resolution Tem ◽

High Degree ◽

Degree Of Order

The objective of our work is to determine:a) whether both of the imaging methods (TEM, STM) yield comparable data andb) which method is better suited for a reliable structure analysis of microclusters smaller than 1.5 nm, where a deviation of the bulk structure is expected.The silver was evaporated in a bell-jar system (p 10−5 pa) and deposited onto a 6 nm thick amorphous carbon film and a freshly cleaved highly oriented pyrolytic graphite (HOPG).The average deposited Ag thickness is 0.1 nm, controlled by a quartz crystal microbalance at a deposition rate of 0.02 nm/sec. The high resolution TEM investigations (100 kV) were executed by a hollow-cone illumination (HCI). For the STM investigations a commercial STM was used. With special vibration isolation we achieved a resolution of 0.06 nm (inserted diffraction image in Fig. 1c). The carbon film shows the remarkable reduction in noise by using HCI (Fig. 1a). The HOPG substrate (Fig. 1b), cleaved in sheets thinner than 30 nm for the TEM investigations, shows the typical arrangement of a nearly perfect stacking order and varying degrees of rotational disorder (i.e. artificial single crystals). The STM image (Fig. 1c) demonstrates the high degree of order in HOPG with atomic resolution.

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Carbon Supports Mitigate Resistivity Limitations in Ni-Mo Alkaline Hydrogen Evolution Electrocatalysts

10.26434/chemrxiv.7037264.v1 ◽

2018 ◽

Author(s):

Rituja Patil ◽

Aayush Mantri ◽

Stephen House ◽

Judith C. Yang ◽

James McKone

Keyword(s):

Oxide Layer ◽

Hydrogen Evolution ◽

Interfacial Resistance ◽

Carbon Supports ◽

Vulcan Carbon

We have studied the composition and morphology of Ni-Mo alloys. These alloys consist of a Ni-rich core surrounded by Mo-rich oxide layer. The HER activity of Ni-Mo alloys was seen to be limited by interfacial resistance rather than kinetic and solution transport. Vulcan carbon, a conductive support mitigate the resistive limitations by providing conductive percolation networks.

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Transition-Metal Nanoparticle Catalysts Anchored on Carbon Supports via Short-Chain Alginate Linkers

ACS Applied Nano Materials ◽

10.1021/acsanm.1c00294 ◽

2021 ◽

Author(s):

Joakim Tafjord ◽

Erling Rytter ◽

Anders Holmen ◽

Rune Myrstad ◽

Ingeborg-Helene Svenum ◽

...

Keyword(s):

Transition Metal ◽

Metal Nanoparticle ◽

Short Chain ◽

Carbon Supports ◽

Nanoparticle Catalysts

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Comparison of TEM and STM observations of small silver clusters on different carbon supports

phys stat sol (a) ◽

10.1002/pssa.2211310105 ◽

1992 ◽

Vol 131 (1) ◽

pp. 27-27

Author(s):

B. Tesche ◽

T. Schilling

Keyword(s):

Silver Clusters ◽

Carbon Supports

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Hierarchical Porous, N-Containing Carbon Supports for High Loading Sulfur Cathodes

Nanomaterials ◽

10.3390/nano11020408 ◽

2021 ◽

Vol 11 (2) ◽

pp. 408

Author(s):

Jae-Woo Park ◽

Hyun Jin Hwang ◽

Hui-Ju Kang ◽

Gazi A. K. M. Rafiqul Bari ◽

Tae-Gyu Lee ◽

...

Keyword(s):

High Energy ◽

High Energy Density ◽

High Loading ◽

Carbon Supports ◽

Structure Directing Agent ◽

Shuttle Effect ◽

Main Challenge ◽

Hierarchical Porous ◽

Hollow Carbon ◽

A Minor

The lithium-polysulfide (LiPS) dissolution from the cathode to the organic electrolyte is the main challenge for high-energy-density lithium-sulfur batteries (LSBs). Herein, we present a multi-functional porous carbon, melamine cyanurate (MCA)-glucose-derived carbon (MGC), with superior porosity, electrical conductivity, and polysulfide affinity as an efficient sulfur support to mitigate the shuttle effect. MGC is prepared via a reactive templating approach, wherein the organic MCA crystals are utilized as the pore-/micro-structure-directing agent and nitrogen source. The homogeneous coating of spherical MCA crystal particles with glucose followed by carbonization at 600 °C leads to the formation of hierarchical porous hollow carbon spheres with abundant pyridinic N-functional groups without losing their microstructural ordering. Moreover, MGC enables facile penetration and intensive anchoring of LiPS, especially under high loading sulfur conditions. Consequently, the MGC cathode exhibited a high areal capacity of 5.79 mAh cm−2 at 1 mA cm−2 and high loading sulfur of 6.0 mg cm−2 with a minor capacity decay rate of 0.18% per cycle for 100 cycles.

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