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Title: Interfacial Cu + promoted surface reactivity: Carbon monoxide oxidation reaction over polycrystalline copper-titania catalysts

We have studied the catalytic carbon monoxide (CO) oxidation (CO+0.5O2 → CO2) reaction using a powder catalyst composed of both copper (5wt% loading) and titania (CuOx-TiO2). Our study was focused on revealing the role of Cu, and the interaction between Cu and TiO2, by systematic comparison between two nanocatalysts, CuOx-TiO2 and pure CuOx. We interrogated these catalysts under in situ conditions using X-ray Diffraction (XRD), X-ray Absorption Fine Structure (XAFS) and Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) to probe the structure and electronic properties of the catalyst at all stages of the reaction and simultaneously probe the surface states or intermediates of this reaction. With the aid of several ex situ characterization techniques including Transmission Electron Microscopy (TEM), the local catalyst morphology and structure was also studied. Our results show that a CuOx-TiO2 system is more active than bulk CuOx for the CO oxidation reaction due to its lower onset temperature and better stability at higher temperatures. Our results also suggests that a surface Cu+ species observed in the CuOx-TiO2 interface are likely to be a key player in the CO oxidation mechanism, while implicating that the stabilization of this species is probably associated with the oxide-oxide interface. Bothmore » in situ DRIFTS and XAFS measurements reveal that there is likely to be a Cu(Ti)-O mixed oxide at this interface. We discuss the nature of this Cu(Ti)-O interface and interpret its role on the CO oxidation reaction.« less
 [1] ;  [2] ;  [1] ;  [3] ;  [4] ;  [1] ;  [3] ;  [1] ;  [1] ;  [4] ;  [3] ;  [1] ;  [5]
  1. Brookhaven National Lab. (BNL), Upton, NY (United States)
  2. City College of New York, NY (United States)
  3. Stony Brook Univ., NY (United States)
  4. Yeshiva Univ., New York, NY (United States)
  5. Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., NY (United States)
Publication Date:
OSTI Identifier:
Report Number(s):
Journal ID: ISSN 0039-6028; R&D Project: CO009; KC0302010
Grant/Contract Number:
SC00112704; SC0012704; FG02-03ER15476; SC0012335
Accepted Manuscript
Journal Name:
Surface Science
Additional Journal Information:
Journal Volume: 652; Journal ID: ISSN 0039-6028
Research Org:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States