Statistical studies of adsorption isotherms of iron nitrate and iron chloride on a thin layer of porphyrin

In this paper, we report a simple growth of carbon nanofibers by means of the combustion of ethyl alcohol. In our experiment, copper plate was employed as substrate, iron nitrate and iron chloride as catalyst precursor and ethanol as carbon source. The as-grown carbon nanofibers were characterized by employing scanning electron microscopy, transmission electron microscopy, high-resolution field-emission transmission electron microscopy and Reinshaw optical confocal Raman spectroscopy. Our results suggested that it would tend to form relatively uniform nanofibers when the catalyst precursor was iron nitrate, however, to form some helical structure nanofibers when the catalyst precursor was iron chloride. The sample using iron chloride as the catalyst precursor has a higher graphitization degree than that using iron nitrate as the catalyst precursor.

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Synthetic Bio-Graphene Based Nanomaterials through Different Iron Catalysts

Nanomaterials ◽

10.3390/nano8100840 ◽

2018 ◽

Vol 8 (10) ◽

pp. 840 ◽

Cited By ~ 5

Author(s):

Qiangu Yan ◽

Jinghao Li ◽

Xuefeng Zhang ◽

Jilei Zhang ◽

Zhiyong Cai

Keyword(s):

Electron Microscopy ◽

Catalytic Decomposition ◽

Decomposition Methods ◽

Iron Chloride ◽

Iron Catalysts ◽

Residual Chlorine ◽

Iron Nitrate ◽

Iron Salts ◽

Temperature Programmed ◽

Temperature Programmed Decomposition

Kraft lignin was catalytically graphitized to graphene-based nanostructures at 1000 °C under argon atmosphere with four iron catalysts, iron(III) nitrate (Fe-N); iron(II) chloride (Fe-Cl2); iron(III) chloride (Fe-Cl3); and iron(II) sulfate (Fe-S). The catalytic decomposition process of iron-promoted lignin materials was examined using thermalgravimetric analysis and temperature-programmed decomposition methods. The crystal structure, morphology and surface area of produced materials were characterized by means of X-ray diffraction, Raman, scanning electron microscopy, high resolution transmission electron microscopy and N2 adsorption−desorption techniques. Experimental results indicated that iron nitrate catalyst had better iron dispersion three other iron salts. Iron nitrate was the most active catalyst among four iron salts. The low activity of iron in iron chloride-promoted samples was because the residual chlorine over iron surfaces prevent iron interaction with lignin functional groups.

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Applications of Photoelectron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100092499 ◽

1976 ◽

Vol 34 ◽

pp. 506-507

Author(s):

William J. Baxter

Keyword(s):

Electron Microscopy ◽

Thermal Decomposition ◽

Chemical Composition ◽

Ultraviolet Radiation ◽

Thin Layer ◽

Edge Effects ◽

Electron Optics ◽

Surface Layers ◽

Crystalline Orientation ◽

Fluorescent Screen

In this form of electron microscopy, photoelectrons emitted from a metal by ultraviolet radiation are accelerated and imaged onto a fluorescent screen by conventional electron optics. image contrast is determined by spatial variations in the intensity of the photoemission. The dominant source of contrast is due to changes in the photoelectric work function, between surfaces of different crystalline orientation, or different chemical composition. Topographical variations produce a relatively weak contrast due to shadowing and edge effects.Since the photoelectrons originate from the surface layers (e.g. ∼5-10 nm for metals), photoelectron microscopy is surface sensitive. Thus to see the microstructure of a metal the thin layer (∼3 nm) of surface oxide must be removed, either by ion bombardment or by thermal decomposition in the vacuum of the microscope.

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