GI-EDIXS for the Determination of the Oxidation State of Titanium Surface Films

JOSÉ ROBLEDO; JUAN JOSÉ LEANI; FABIANA Y. OLIVA; MANUEL GARCÍA; OSVALDO CÁMARA; HÉCTOR J. SÁNCHEZ

Girona

Conferencia; 18th International Conference on Total Reflection X-ray Fluorescence Analysis and Related Methods (TXRF 2019); 2019

Titanium is a transition element which is frequently used in technological materials. From medical prosthetic implants to substrate for Li-ion batteries, titanium is a major constituent element that requires a constant characterization [1-3]. One of the most serious problem of titanium analysis is to discriminate Ti(III) from Ti(IV). In this work we use the EDIXS technique [4] in grazing incidence conditions, to analyze titanium electrodes with several state of charge in order to determine the oxidation state of the electrode in different surface nanolayers.The measurements were carried out at the Brazilian Synchrotron Light Source (LNLS, Campinas) in the D09B beamline and at the IAEA end-station of the XRF-beamline at Elettra Sincrotrone Trieste (Italy). A grazing incidence angle scan was performed to study the chemical environment at different depths of the sample. Several samples with different charge treatments were studied.In order to discriminate changes on the titanium chemical state of the electrodes, a Multivariate Methods was applied on the RIXS spectra.The results show that it is possible to perform a depth profiling analysis of oxidation states by mean of the EDIXS technique. These analyses are quite difficult or even impossible to achieve by conventional spectroscopic techniques.Titanium electrodes present a very specific surface distribution of chemical environments.