Depth Profiling Nano-Analysis of Chemical Environments using Resonant Raman Spectroscopy at Grazing Incidence Conditions

LEANI J.; H. J. SÁNCHEZ; PEREZ, R.D; PEREZ, C.A.

ANALYTICAL CHEMISTRY

AMER CHEMICAL SOC

Lugar: Washington; Año: 2013 vol. 85 p. 7069 - 7075

0003-2700

Both X-ray total reflection and X-ray Raman scattering techniques were 8 combined to discriminate chemical environments in depth-profiling studies using an 9 energy dispersive system. This allowed, for the first time, to resolve oxidation state on 10 surface nanolayers with a low-resolution system. Samples of pure Cu and Fe oxidized in 11 tap water and salty water, respectively, were studied in the Brazilian synchrotron facility 12 using monochromatic radiation and an EDS setup. The measurements were carried out in 13 total reflection geometry with incident energy lower and close to the K absorption edge of 14 both elements. The results allowed observing the presence of very thin oxide layers, 15 usually not observable with conventional geometries of irradiation. They also permit the 16 identification of the compound present in a particular depth of the sample with 17 nanometric, or even subnanometric, resolution using a low-resolution system.