Generation of atomic oxygen on Ag(111) and Ag(110) using NO2: a TPD, LEED, HREELS, XPS and NRA study

Clean atomic oxygen overlayers have been produced on Ag(111) and Ag(110) surfaces by dosing with NO2 between 500–520 K in UHV. These were studied using TPD, LEED, XPS, HREELS, AES and NRA. The high coverage atomic oxygen structures, Ag(111)-(4 × 4)O and Ag(110)-c(6 × 2)O are easily formed in UHV using moderate dosing pressures. The spectroscopic data indicate that these NO2-produced overlayers have the same structure as those produced using oxygen at high pressures. The absolute coverage of the Ag(111)-(4 × 4)O is determined to be 7.07(±0.55) × 1014 O atoms cm−2, or 0.51 ± 0.04 ML. This state is characterized by a single O 1s XPS peak at 528.2 eV. The NO2-produced Ag(111)-(4 × 4)O structure is suggested to be composed of two parts. The outer layer of this phase is composed of a coincidence mesh of a single layer of the (111) plane of Ag2O, which itself is comprised of a Ag plane sandwiched between two oxygen planes. Between this coincidence mesh and the Ag(111) surface is a partial monolayer of chemisorbed oxygen atoms. The c(6 × 2)O structure is characterized by two vibrational loss peaks at 298 and 339 cm−1, a single O 1s XPS peak at 528.5 eV, and a coverage of close to 1 ML.

[1]  B. Sexton,et al.  Vibrational spectra of molecular and atomic oxygen on Ag(11O) , 1980 .

[2]  I. V. Mitchell,et al.  Revisiting the 12C(d, p)13C reaction cross section using condensed gas targets , 1991 .

[3]  B. Koel,et al.  Interaction of oxygen with Pd(111): High effective O2 pressure conditions by using nitrogen dioxide , 1990 .

[4]  Charles T. Campbell,et al.  The interactions of O2, CO and CO2 with Ag(110) , 1984 .

[5]  L. Sneddon,et al.  Oxygen chemisorption on copper (110) , 1987 .

[6]  S. Bare Comparison of ethylene oxide and propylene oxide chemisorbed on clean and oxygen precovered Ag(110) , 1992 .

[7]  J. Davies,et al.  Absolute coverage measurement of adsorbed CO and D2 on platinum , 1980 .

[8]  E. Ferroni,et al.  Chemisorption of oxygen on the silver (111) surface , 1974 .

[9]  J. Davies,et al.  Absolute calibration of 14N(d, α) and 14N(d, p) reactions for surface adsorption studies , 1983 .

[10]  M. Barteau,et al.  Photoelectron spectra of adsorbed carbonates , 1983 .

[11]  P. Alnot,et al.  The adsorption and reactions of NO2 on the Ag(111) surface: I. XPS/UPS and annealing studies between 90 and 300 K , 1990 .

[12]  I. J. Malik,et al.  High coverages and subsurface penetration of oxygen on Ru(001) , 1991 .

[13]  Chua,et al.  O chemisorption on Cu(110) by scanning tunneling microscopy. , 1990, Physical review. B, Condensed matter.

[14]  C. Benndorf,et al.  Oxygen adsorption on Ag(111) in the temperature range from 100 500 K: UPS, XPS and EELS investigations , 1983 .

[15]  B. M. Dekoven,et al.  A laser drilled aperture for use in an ultrahigh vacuum gas doser , 1989 .

[16]  P. Biloen,et al.  Adsorption of oxygen on Ag(110) studied by high resolution ELS and TPD , 1981 .

[17]  M. W. Roberts,et al.  A study of the adsorption of oxygen on silver at high pressure by electron spectroscopy , 1979 .

[18]  Ertl,et al.  Novel mechanism for the formation of chemisorption phases: The (2 x 1)O-Cu(110) "added row" reconstruction. , 1990, Physical review letters.

[19]  B. Koel,et al.  Study of high coverages of atomic oxygen on the Pt(111) surface , 1989 .

[20]  T. Sakurai,et al.  Boundary structures of the (n×1) added rows of AgO chains on a Ag(110) surface , 1992 .

[21]  I. Stensgaard,et al.  Oxygen-adsorption induced reconstruction of Cu(110) studied by high energy ion scattering , 1983 .

[22]  J. Nørskov,et al.  Oxygen chemisorption on metal surfaces: General trends for Cu, Ni and Ag , 1993 .

[23]  H. Engelhardt,et al.  Adsorption of oxygen on silver single crystal surfaces , 1976 .

[24]  Charles T. Campbell,et al.  Atomic and molecular oxygen adsorption on Ag(111) , 1985 .

[25]  C. DiMaggio,et al.  The adsorption of nitrogen dioxide on the Ag(110) surface and formation of a surface nitrate , 1987 .

[26]  W. H. Weinberg,et al.  An XPS and UPS study of the kinetics of carbon monoxide oxidation over Ag(111) , 1982 .

[27]  J. Wendelken,et al.  High coverages of oxygen on Cu(110) investigated with XPS, LEED, and HREELS , 1991 .