Partial reduction of Si(IV) in SiO<sub>2</sub> thin film by deposited metal particles: an XPS study

Komiyama, Masaharu; Shimaguchi, Takemi

doi:10.1002/sia.1034

Cited by 18 publications

(14 citation statements)

References 25 publications

(21 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similar work function changes for Ni/TiO 2 , 25 Ag/MgO, 19 and Cu/ZnO 22 have been interpreted in terms of charge transfer from the metal to the oxides. Previous XPS studies have also indicated that charge transfer from Ag to SiO 2 takes place, 26 consistent with the present data. Also, recent theoretical calculations for the Cu/SiO 2 system have shown that metal clusters can become charge-deficient on a perfect SiO 2 surface, leading to electrostatic bonding between the metal cluster and two nearest-neighbor O atoms.…”

Section: Resultssupporting

confidence: 95%

Ag Adsorption on Various Silica Thin Films

et al. 2003

View full text Add to dashboard Cite

Various defect sites on SiO2 thin films on Mo(112) have been characterized with metastable impact electron spectroscopy (MIES), and the interaction between deposited Ag and these defects sites investigated with MIES/ultraviolet photoelectron spectroscopy (UPS). MIES/UPS data for low-and high-defect SiO 2 surfaces acquired as a function of Ag exposure are consistent with two-dimensional Ag growth at low coverage and three-dimensional growth at higher Ag coverages. With increasing defect density on the SiO 2 surfaces, no significant change is observed in the behavior of the work function with respect to the Ag coverage, suggesting that the interaction between Ag and SiO 2 is not influenced markedly by the presence of defects. This result is consistent with recent theoretical results that indicate a strong covalent bond between an overlayer metal and defect sites of SiO 2.

show abstract

Section: Resultssupporting

confidence: 95%

Ag Adsorption on Various Silica Thin Films

et al. 2003

View full text Add to dashboard Cite

show abstract

“…The authors discuss the formation of covalent bonds between the silver nanoparticles and the defect centers of the SiO 2 film during their investigation by metastable pulse electronic spectroscopy and ultraviolet photoelectron spectroscopy. The silver clusters carry a positive charge as a result of electron transfer from the Ag to the SiO 2 with partial reduction of the Si(IV) [53]. The analogous situation for gold was discussed in [54].…”

Section: Introductionmentioning

confidence: 92%

Silver and gold nanoparticles in silica matrices: synthesis, properties, and application

et al. 2010

View full text Add to dashboard Cite

Methods of synthesis, optical characteristics, morphology, and catalytic and bactericidal characteristics of composite materials based on silica (films and powders) containing nanoparticles of silver, gold, and their binary compounds with alloy or core-shell structure are examined. The photochemical reduction of Au 3+ and Ag + with a photocatalyst (a film of SiO 2 with adsorbed benzophenone) makes it possible to generate stable nanoparticles of gold and silver in solutions for subsequent introduction into adsorbents and catalysts. Examples of the use of nanosized composites in catalysis and in microbiological experiments are presented.

show abstract

“…6, and also expressed as equivalent H 2 consumption per Cu atom, assuming reduction of CuO. The reduction of the unpromoted Cu/SiO 2 catalyst is completed at 700 K when the H 2 /Cu ratio equals 1; the further weight loss at T red > 800 K may be attributed to either reduction or sintering of the silica support [26,27]. For high-loaded Al 2 O 3 supported systems it was reported that N 2 O passivation induced modification of the Cu particle structure, ascribed to the heat of dissociative adsorption [28]; a H 2 TPD method was suggested by these authors to selectively measure the Cu metal area.…”

Section: Thermogravimetrymentioning

confidence: 99%

The effect of the reduction temperature on the structure of Cu/ZnO/SiO2 catalysts for methanol synthesis

Batyrev

Heuvel

Beckers

et al. 2005

Journal of Catalysis

View full text Add to dashboard Cite

The effect of the reduction temperature on the structure of Cu/ZnO/SiO2 catalysts for methanol synthesis Batyrev, E.; van den Heuvel, J.C.; Beckers, J.; Jansen, W.P.A.; Castricum, H.L. General rightsIt is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulationsIf you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Abstract: The structure of Cu/SiO 2 and Cu/ZnO/SiO 2 catalysts was studied after reduction at 450-1300 K. The influence of the ZnO promoter on the exposed Cu surface area and metal cluster size was determined by N 2 O chemisorption and X-ray diffraction. After reduction at 450 K, the metal surface area amounted to 9 m 2 /g cat for both catalysts. Oxygen uptake during N 2 O chemisorption increased significantly up to reduction temperatures of 800-900 K. This increase was most prominent for the ZnO-promoted catalyst, although no oxygen uptake was observed for a similarly treated ZnO/SiO 2 sample. The behaviour of the promoted catalyst can be explained by formation of Zn 0 , surface alloying, and segregation of ZnO x species on top of Cu clusters. The high thermostability of the catalysts was confirmed by in-situ XRD measurements. The Cu crystallite size in both catalysts was about 4 nm, and did not increase when the reduction temperature was raised to 1100 K for 1 hour.

show abstract

Partial reduction of Si(IV) in SiO₂ thin film by deposited metal particles: an XPS study

Cited by 18 publications

References 25 publications

Ag Adsorption on Various Silica Thin Films

Ag Adsorption on Various Silica Thin Films

Silver and gold nanoparticles in silica matrices: synthesis, properties, and application

The effect of the reduction temperature on the structure of Cu/ZnO/SiO2 catalysts for methanol synthesis

Contact Info

Product

Resources

About

Partial reduction of Si(IV) in SiO2 thin film by deposited metal particles: an XPS study

Cited by 18 publications

References 25 publications

Ag Adsorption on Various Silica Thin Films

Ag Adsorption on Various Silica Thin Films

Silver and gold nanoparticles in silica matrices: synthesis, properties, and application

The effect of the reduction temperature on the structure of Cu/ZnO/SiO2 catalysts for methanol synthesis

Contact Info

Product

Resources

About

Partial reduction of Si(IV) in SiO₂ thin film by deposited metal particles: an XPS study