Surface oxygen

P.J. Goddard, and R.M. Lambert, Basic studies of the oxygen surface chemistry of silver Oxygen, dioxygen, oxide and superoxide on rubidium-dosedAg(l 1 ),Surf. Sci. 107,519-532(1981). 

Keywords Cycloadditions, Chemical orbital theory. Donor-acceptor interaction. Electron delocalization band. Electron transfer band, Erontier orbital. Mechanistic spectrum, NAD(P)H reactions. Orbital amplitude. Orbital interaction. Orbital phase. Pseudoexcitation band. Quasi-intermediate, Reactivity, Selectivity, Singlet oxygen. Surface reactions... 

An XPS Investigation of iron Fischer-Tropsch catalysts before and after exposure to realistic reaction conditions is reported. The iron catalyst used in the study was a moderate surface area (15M /g) iron powder with and without 0.6 wt.% K2CO3. Upon reduction, surface oxide on the fresh catalyst is converted to metallic iron and the K2CO3 promoter decomposes into a potassium-oxygen surface complex. Under reaction conditions, the iron catalyst is converted to iron carbide and surface carbon deposition occurs. The nature of this carbon deposit is highly dependent on reaction conditions and the presence of surface alkali. 

Kim KS, Winograd N, Davis RE. 1971. Electron spectroscopy of platinum-oxygen surfaces and application to electrochemical studies. J Am Chem Soc 93 6296-6297. 

Time-dependent evolution of the gas-phase O atom signal at Etrans —0.19eV. At t = 0 the monitoring starts and is completed at t = 600 s when the oxygen surface coverage at the Al(lll) surface is 0.2. (Reproduced from Ref. 40). 

At high temperatures (> 170 K), the water desorbs and so the autocatalytic reaction cannot be sustained and is an explanation for why the H2 + 02 reaction slows, the formation of OH species now being solely dependent on the H(a) + O(a) reaction, which is the slowest step in the above scheme. That the water + oxygen reaction was fast and facile was evident from the spectroscopic studies at both nickel and zinc surfaces, when the oxygen surface coverage was low and involving isolated oxygen adatoms. 

G. D. Moggridge, J. P. S. Badyal and R. M. Lambert, X-ray photoelectron spetroscopic characterisation of oxygen surface species on a doubly promoted manganese oxide model planar catalyst significance for CH4 coupling, J. Phys. Chem., 1990, 94, 508. 

Table 8.4. Relative oxygen surface mobility for some oxides at 400°C (base 10 for alumina)...

Oxygen Diffusion Coefficient (D ), Oxygen Surface Exchange Coefficient (Ar), and Oxygen Ionic Conductivity (tr,) of LaMn03-Based Oxides Measured by SIMS Technique... 

Formation of Metal—Oxygen Surface Compounds on Copper, Silver, and Gold Electrodes... 

SAWYER AND CHOOTO Format bn of Metal—Oxygen Surface Compounds All... 

SAWYER AND CHOOTO Formation of Metal-Oxygen Surface Compounds 479... 

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