Characterisation of the Ru/MgF2 catalyst with adsorbed O2, NO, CO probe molecules by EPR and IR spectroscopy

2006 ◽  
Vol 67 (7) ◽  
pp. 1387-1393 ◽  
Author(s):  
J. Goslar ◽  
M. Wojciechowska ◽  
M. Zieliński
Keyword(s):  
Ir Spectroscopy ◽  
Probe Molecules ◽  
Co Probe

Determination of the Acidity of High Surface AlF3by IR Spectroscopy of Adsorbed CO Probe Molecules

2007 ◽  
Vol 111 (49) ◽  
pp. 18317-18325 ◽  
Author(s):  
Thoralf Krahl ◽  
Alexandre Vimont ◽  
Gehan Eltanany ◽  
Marco Daturi ◽  
Erhard Kemnitz
Keyword(s):  
Ir Spectroscopy ◽  
High Surface ◽  
Probe Molecules ◽  
Co Probe ◽  
Adsorbed Co

scholarly journals The Properties of Cu Ions in Zeolites CuY Studied by IR Spectroscopy

Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4686
Author(s):  
Jerzy Podobiński ◽  
Mariusz Gackowski ◽  
Grzegorz Mordarski ◽  
Katarzyna Samson ◽  
Michał Śliwa ◽  
...  
Keyword(s):  
Ir Spectroscopy ◽  
Positive Charge ◽  
Co Adsorption ◽  
The Other ◽  
Probe Molecules ◽  
Adsorption And Desorption ◽  
Other Hand ◽  
Close Proximity ◽  
No And Co Adsorption ◽  
Cu Ions

The properties of both Cu2+ and Cu+ ions in zeolite CuY were followed with NO and CO as probe molecules. Cu2+ was found to be located in SII, SII*, and SIII sites, whereas Cu+ was found in SII and SII* sites. The fine analysis of the spectra of Cu2+-NO and Cu+-CO adducts suggests that both in SII and in SII* sites two kinds of Cu cations exist. They differ in the positive charge, which may be related to the varying numbers of AlO4− in close proximity. The experiments of NO and CO adsorption and desorption evidenced that both Cu2+ and Cu+ sites of highest positive charge bind probe molecules most strongly but activate them to a lesser extent than the Cu sites of lowest positive charge. The experiments of reduction with hydrogen evidenced that the Cu ions of higher positive charge are first reduced by hydrogen. On the other hand, Cu sites of the lowest positive charge are first oxidized by oxygen. The experiments with CuNaY zeolites of various Cu contents suggest that the first introduced Cu (at low Cu contents) created Cu+, which was the most neutralized by framework oxygens. Such Cu cations are the most stabilized by framework oxygens.

scholarly journals Reduction and Oxidation of Cu Species in Cu-Faujasites Studied by IR Spectroscopy

Molecules ◽  
2020 ◽  
Vol 25 (20) ◽  
pp. 4765
Author(s):  
Łukasz Kuterasiński ◽  
Jerzy Podobiński ◽  
Ewa Madej ◽  
Małgorzata Smoliło-Utrata ◽  
Dorota Rutkowska-Zbik ◽  
...  
Keyword(s):  
Ir Spectroscopy ◽  
Room Temperature ◽  
Probe Molecules ◽  
First Order ◽  
Reduction And Oxidation

The process of reduction (by hydrogen and ethanol) and oxidation (by oxygen and NO) of Cu sites in dealuminated faujasite-type zeolites (of Si/Al = 31) was studied by infrared (IR) spectroscopy with CO (for Cu+) and NO (for Cu2+) as probe molecules. Two zeolites were studied: one of them contained mostly Cu+exch., whereas another one contained mostly Cu2+ and Cu+ox. The susceptibility of various forms of Cu for reduction were investigated. IR experiments of CO sorption evidenced that Cu+ox. was more prone for the reduction than Cu+exch. According to NO sorption studies, Cu2+exch. was reduced in the first order before Cu2+ox. Ethanol reduced mostly Cu2+ and, also, some amounts of Cu+. The treatment with oxygen caused the oxidation of Cu+ (both Cu+exch. and Cu+ox.) to Cu2+. The adsorption of NO at 190K produced Cu+(NO)2 dinitrosyls, but heating to room temperature transformed dinitrosyls to mononitrosyls and increased the Cu2+ content.

Determination of Acid Site Location in Dealuminated MCM-68 by 27Al MQMAS NMR and FT-IR Spectroscopy with Probe Molecules

2018 ◽  
Vol 122 (2) ◽  
pp. 1180-1191 ◽  
Author(s):  
Ryoichi Otomo ◽  
Toshiki Nishitoba ◽  
Ryota Osuga ◽  
Yusuke Kunitake ◽  
Yuichi Kamiya ◽  
...  
Keyword(s):  
Ir Spectroscopy ◽  
Acid Site ◽  
Probe Molecules ◽  
Site Location ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

Characterization of Gallosilicate MFI-Type Zeolites by IR Spectroscopy of Adsorbed Probe Molecules

1996 ◽  
Vol 100 (16) ◽  
pp. 6678-6690 ◽  
Author(s):  
C. Otero Areán ◽  
G. Turnes Palomino ◽  
F. Geobaldo ◽  
A. Zecchina
Keyword(s):  
Ir Spectroscopy ◽  
Probe Molecules

Interaction of CO probe molecules with Cu(+) in MCM-22 zeolite

2014 ◽  
Vol 186 ◽  
pp. 37-45 ◽  
Author(s):  
Karel Frolich ◽  
Roman Bulánek ◽  
Eva Frýdová
Keyword(s):  
Probe Molecules ◽  
Co Probe

scholarly journals IR Studies of the Cu Ions in Cu-Faujasites

Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4250
Author(s):  
Łukasz Kuterasiński ◽  
Jerzy Podobiński ◽  
Dorota Rutkowska-Zbik ◽  
Jerzy Datka
Keyword(s):  
Ir Spectroscopy ◽  
Co Adsorption ◽  
Electron Donors ◽  
Probe Molecules ◽  
Adsorbed Molecules ◽  
Ir Studies ◽  
Square Planar ◽  
Cu Ions

The properties of Cu ions in dealuminated faujasite-type zeolites (Si/Al = 31) containing 1, 2, and 5 wt.% of Cu were investigated by IR spectroscopy with CO and NO as probe molecules. Cu was introduced by impregnation into zeolites in both protonic (HFAU) and sodium (NaFAU) forms of zeolite. Four kinds of Cu species were found: Cu+exch., Cu+oxide, Cu2+exch. (square, planar, and square pyramidal), and Cu2+oxide (CuO). The proportions between these four kinds of Cu depended on the amount of Cu and on the form of zeolite to which Cu was introduced (HFAU or NaFAU). Zeolites with 1 wt.% of Cu introduced to HFAU (denoted as Cu(1)HFAU) contained only Cu+exch., whereas other forms of Cu were present in zeolites of higher Cu contents. The concentration of Cu+exch. was determined by quantitative IR studies of CO adsorption. According to the IR results, some Cu ions were situated inside hexagonal prisms and/or cuboctahedra, and were inaccessible to adsorbed molecules. IR studies also evidenced that Cu ions in oxide forms—Cu+oxide and Cu2+oxide (CuO)—were better electron donors than Cu in exchange positions (Cu+exch. and Cu2+exch).

IR SPECTROSCOPY WITH SURFACE ELECTROMAGNETIC WAVES

1984 ◽  
Vol 45 (C5) ◽  
pp. C5-167-C5-178
Author(s):  
A. J. Sievers ◽  
Z. Schlesinger ◽  
Y. J. Chabal
Keyword(s):  
Ir Spectroscopy ◽  
Electromagnetic Waves ◽  
Surface Electromagnetic Waves
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