The effects of the specific adsorption of anion on the reactivity of the Ru(0001) surface towards CO adsorption and oxidation: in situ FTIRS studies

2008 ◽  
Vol 10 (25) ◽  
pp. 3774 ◽  
Author(s):  
J. M. Jin ◽  
W. F. Lin ◽  
P. A. Christensen
Keyword(s):  
Co Adsorption ◽  
Specific Adsorption ◽  
In Situ Ftirs

scholarly journals Removal of Cd(II) from Micro-Polluted Water by Magnetic Core-Shell Fe3O4@Prussian Blue

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2497
Author(s):  
Xinxin Long ◽  
Huanyu Chen ◽  
Tijun Huang ◽  
Yajing Zhang ◽  
Yifeng Lu ◽  
...  
Keyword(s):  
Prussian Blue ◽  
Co Adsorption ◽  
Magnetic Core ◽  
Diameter Distribution ◽  
Polluted Water ◽  
Core Shell ◽  
Freundlich Model ◽  
Rate Limiting Step ◽  
Rate Limiting

A novel core-shell magnetic Prussian blue-coated Fe3O4 composites (Fe3O4@PB) were designed and synthesized by in-situ replication and controlled etching of iron oxide (Fe3O4) to eliminate Cd (II) from micro-polluted water. The core-shell structure was confirmed by TEM, and the composites were characterized by XRD and FTIR. The pore diameter distribution from BET measurement revealed the micropore-dominated structure of Fe3O4@PB. The effects of adsorbents dosage, pH, and co-existing ions were investigated. Batch results revealed that the Cd (II) adsorption was very fast initially and reached equilibrium after 4 h. A pH of 6 was favorable for Cd (II) adsorption on Fe3O4@PB. The adsorption rate reached 98.78% at an initial Cd (II) concentration of 100 μg/L. The adsorption kinetics indicated that the pseudo-first-order and Elovich models could best describe the Cd (II) adsorption onto Fe3O4@PB, indicating that the sorption of Cd (II) ions on the binding sites of Fe3O4@PB was the main rate-limiting step of adsorption. The adsorption isotherm well fitted the Freundlich model with a maximum capacity of 9.25 mg·g−1 of Cd (II). The adsorption of Cd (II) on the Fe3O4@PB was affected by co-existing ions, including Cu (II), Ni (II), and Zn (II), due to the competitive effect of the co-adsorption of Cd (II) with other co-existing ions.

In situ AFM and XPS Investigation of U6+ Reduction by Fe2+ on Hematite and Pyrite

2012 ◽  
Vol 1444 ◽  
Author(s):  
Jingjie Niu ◽  
Udo Becker ◽  
Rodney Ewing
Keyword(s):  
Charge Transfer ◽  
Co Adsorption ◽  
Reduction Rate ◽  
Mulliken Charge ◽  
Quantum Mechanical ◽  
Quantum Mechanical Calculations ◽  
Initial Ph ◽  
Adsorption Reduction ◽  
Tapping Mode Afm

ABSTRACTUranyl adsorption/reduction by Fe2+ on hematite and pyrite has been studied at neutral pH under anoxic and CO2-free conditions. XPS results confirm that more U3O8 precipitates on hematite than on pyrite reacted for 24 h in 160 μM uranyl nitrate and 160 μM Fe2+ solution at initial pH 7.3. These results are explained in terms of co-adsorption energy and U atom Mulliken charge transfer by quantum mechanical calculations. Moreover, in situ fluid tapping-mode AFM experiments on hematite indicate a deceleration of the U reduction rate within 24 h due to the passivation of the surface caused by the formation of orthorhombic U3O8 crystals. In addition, crystals observed using AFM show morphologies of orthorhombic schoepite appearing on hematite after 5 h.

The dissimilar twins – a comparative, site-selective in situ study of CO adsorption and desorption on Pt(322) and Pt(355)

2007 ◽  
Vol 601 (4) ◽  
pp. 1108-1117 ◽  
Author(s):  
B. Tränkenschuh ◽  
C. Papp ◽  
T. Fuhrmann ◽  
R. Denecke ◽  
H.-P. Steinrück
Keyword(s):  
Co Adsorption ◽  
Adsorption And Desorption ◽  
In Situ Study ◽  
Site Selective

Voltammetric and in situ FTIRS study of the electrochemical oxidation of aniline from aqueous solutions buffered at pH 5

2001 ◽  
Vol 501 (1-2) ◽  
pp. 186-192 ◽  
Author(s):  
F. Cases ◽  
F. Huerta ◽  
P. Garcés ◽  
E. Morallón ◽  
J.L. Vázquez
Keyword(s):  
Aqueous Solutions ◽  
Electrochemical Oxidation ◽  
In Situ Ftirs

scholarly journals Determining the Location of Co2+ in Zeolites by UV-Vis Diffuse Reflection Spectroscopy: A Critical View

Catalysts ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 123 ◽  
Author(s):  
Andrea Bellmann ◽  
Christine Rautenberg ◽  
Ursula Bentrup ◽  
Angelika Brückner
Keyword(s):  
Diffuse Reflection ◽  
Co Adsorption ◽  
In Situ Ftir ◽  
Diffuse Reflection Spectroscopy ◽  
Reflection Spectroscopy ◽  
Oxide Supports ◽  
In Situ Ftir Spectroscopy ◽  
Vis Spectroscopy

UV–Vis spectroscopy as well as in situ FTIR spectroscopy of pyridine and CO adsorption were applied to determine the nature of Co species in microporous, mesoporous, and mixed oxide materials like Co–ZSM-5, Co/Na–ZSM-5, Co/Al–SBA-15, and Co/Al2O3–SiO2. Because all sample types show comparable UV–Vis spectra with a characteristic band triplet, the former described UV–Vis band deconvolution method for determination and quantification of individual cationic sites in the zeolite appears doubtful. This is also confirmed by results of pyridine and CO adsorption revealing that all Co–zeolite samples contain two types of Co2+ species located at exchange positions as well as in oxide-like clusters independent of the Co content, while in Co/Al–SBA-15 and Co/Al2O3–SiO2 only Co2+ species in oxide-like clusters occur. Consequently, the measured UV–Vis spectra represent not exclusively isolated Co2+ species, and the characteristic triplet band is not only related to γ-, β-, and α-type Co2+ sites in the zeolite but also to those dispersed on the surface of different oxide supports. The study demonstrates that for proper characterization of the formed Co species, the use of complementary methods is required.

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