Correlation of Relative X-ray Photoelectron Spectroscopy Shake-up Intensity with CuO Particle Size

Abstract

X-ray photoelectron spectroscopy (XPS) analysis of four Cu/SiO2 catalyst systems of different particle sizes of CuO on the surface showed variation in the relative peak area intensities of the shake-up lines to main core levels of the Cu 2p orbitals. These differences were attributed to various degrees of XPS-induced reduction of CuO initially formed on the surface by spin coating copper(II) acetate {Cu-(CH3CO2)2‚H2O, Cu(ac)2} solutions of varying concentration. Changes in Cu L3M4,5M4,5 X-ray excited Auger (XAES) line shapes under time-dependent exposure to the soft Mg KR X-rays revealed that smaller particle sizes were more susceptible to reduction to Cu(+1) than larger ones. The degree of reduction of Cu(+2) to Cu(+1) correlated with measured atomic force microscopic (AFM) particle heights of CuO on these substrates prior to XPS.

Suppression of Charge Recombination Rate in Nanocrystalline SnO2by Thin Coatings of Divalent Oxides in Dye-Sensitized Solar Cells

“…Figure 2(b) shows the Cu 2p XPS spectrum, where the copper acetate treated SnO 2 sample shows a main Cu 2p3/2 peak at 934.2 eV and broad feature of satellite peak centered at 942.1 eV, which is indicative of Cu 2+ species with 3d 9 configuration. [19][20][21] It was reported that the Cu 2p3/2 XPS spectrum for the CuO thin amorphous layer of about 5 Å thick on the Cu 2 O core material had a main peak at 934.6 eV with a series of satellites on the high-binding-energy side, 940.3 and 943.1 eV. 22 Our XPS result indicates that the surface coating of copper acetate results in CuO layer with Cu 2+ state.…”

Annealing Temperature Dependence on the Physicochemical Properties of Copper Oxide Thin Films

“…32 The satellite peaks indicate the formation of CuO. 33 These results are cross matched with the results of XRD. The Cu 2p 3/2 peaks were curve fitted with three species corresponding to Cu 2 O (933.20 eV, FWHM: 1.56 eV), CuO (934.34 eV, FWHM: 1.56 eV) and Cu(OH) 2 (935.61 eV, FWHM: 1.67 eV).…”

Application of a Sulfur Cathode in Nucleophilic Electrolytes for Magnesium/Sulfur Batteries

“…[21][22][23] Additionally, the "shake-up" satellites at approximately 945 eV and 965 eV for the Cu 2p 3/2 and 2p 1/2 core levels, respectively, are associated with the existence of Cu 2+ . 19,27 The XRD, TGA, and XPS results demonstrate the occurrence of chemical bonds between Cu and S in the electrode with Cu as the current collector, which indicates that the S is not only physically loaded on the Cu current collector but also chemically interacts with the Cu substrate by forming of copper sulfides with the mixed valence states of Cu 1+ and Cu 2+ ions. As is widely known, S and polysulfide intermediates are nonconductive and their electrochemical reactions only occur when the S loading thickness on the conductive matrix is within an electron tunneling range.…”