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Titanium electrodes, and general Ti oxide films, play an important role in state-of-the-art devices and technological developments. In this work, titanium oxide thin-films were prepared by electroformation on titanium substrates up to several anodic potential values in different electrolyte compositions. The analysis took into account the cathodic treatment applied in order to modify the thin-film electronic properties. The oxidation state of the surface of the electrodes at different depths was analyzed using the energy-dispersive inelastic X-ray scattering (EDIXS) technique under grazing incidence conditions. The measurements were carried out using monochromatic synchrotron radiation in a dedicated endstation. After RIXS spectra were treated by multivariate methods, the results indicate a well-defined distribution of titanium oxides in the (+3) state as compared to the standard (+4) state, in good agreement with predictions. In addition, this work demonstrates the capability of the GI-EDIXS technique to provide valuable information from nanolayers of technological materials for both industrial and scientific applications. [ABSTRACT FROM AUTHOR]

Energy Dispersive Inelastic X-ray Scattering (EDIXS) is a reliable technique for the discrimination and characterization of local chemical environments. By means of this methodology, the speciation of samples has been attained in a variety of samples and experimental conditions, such as total reflection, grazing incidence, and confocal setups. Until now, due to the requirement of a monochromatic and intense exciting beam, this tool had been applied using exclusively synchrotron radiation sources. We present, for the first time, results of test measurements using EDIXS for chemical characterization implemented in a conventional x-ray tube based laboratory. The results show good discrimination between different iron compounds under study, suggesting the real possibility of rutinary chemical state characterizations of samples by means of EDIXS using a conventional x-ray tube. [ABSTRACT FROM AUTHOR]

The Li4Ti5O12 (LTO) compound has been investigated as an alternative negative electrode material for lithium ion batteries (LIBs), which are being used as energy storage devices in stationary systems as well as for electric vehicles due to their many interesting features. The LTO compound has shown remarkable Li-ion intercalation/de-intercalation reversibility, demonstrating also zero-strain volume change during the cycling process along with notable safety performance. Furthermore, LTO has a high voltage plateau in comparison with other negative material candidates, helping to avoid the deposition of metallic lithium in the dendrite form. Due to its performance and potential application in LIBs, a deep knowledge regarding the behavior of this LTO compound is of high interest. In this work, energy-dispersive resonant inelastic X-ray scattering (EDIXS) is used to fulfill this need. In addition, XANES measurements were carried out as complementary methodology. The results indicate that EDIXS can differentiate LTO chemical compounds (lithiated and de-lithiated) with high sensitivity, and is a reliable tool to perform chemical speciation analysis on such samples. In addition, the results confirm theoretical predictions regarding the composition of different oxidation states of titanium associated with different states of charge/lithiation of the LTO-spinel also. The proposed methodology can be easily applied to other lithium-based materials and beyond them, such as those based on sodium and novel technologies based on polyvalent cations including magnesium and aluminium. [ABSTRACT FROM AUTHOR]

This work presents an overview of a novel spectroscopic tool: Energy Dispersive Inelastic X-ray Scattering (EDIXS) spectroscopy. By the application of EDIXS, the local chemical environment of an element of interest can be characterized in a variety of experimental conditions. EDIXS makes use of core-level resonant inelastic X-ray scattering (RIXS), taking advantage of the benefits of an energy dispersive detection system and multivariate methods for the data analysis. As result, the proposed methodology presents a fast acquisition, energy-scanning free experiments, low self-absorption effects and an objective interpretation of the data. In this review a first section providing an introduction to the evolution of RIXS and the development of the EDIXS methodology is presented. After that, a theoretical frame from two different approaches is offered, presenting several aspects of the RIXS spectrum features and letting glimpse the origin of the peak fine structure, key issue of this technique. Next, an explanation of the different multivariate methods used for the data analysis is provided. By the end, a set of experimental results obtained with EDIXS are revised, including several irradiation geometries and setups (as total reflection, grazing incidence and even confocal) for a variety of samples. A brief summary with further discussions regarding the advantages of the presented methodology, including future perspectives as its applicability to different X-ray sources, are giving closure to the paper. Unlabelled Image • A novel spectroscopic tool for chemical states determinations is presented. • Some benefits are fast acquisition and low self-absorption avoiding energy scans. • EDIXS can be applied in several irradiation geometries and experimental setups. • Spatial- and time-resolved results are provided and discussed. • Applications using other X-ray sources are possible and considered. [ABSTRACT FROM AUTHOR]

Energy-Dispersive Inelastic X-Ray Scattering (EDIXS) spectroscopy allows for the speciation of various samples under diverse experimental conditions such as total reflection, grazing incidence, and even confocal setups. Until now, this discrimination methodology had been limited only to K lines, which correspond to transitions from L to K inner shells. Because of this, there was a lack of knowledge about the applicability of this method for the discrimination of compounds by the analysis of L lines (transitions from the M to the L atomic shells). This limitation is especially relevant when studying rare earth and heavier elements. In this work, the first results of speciation of erbium and praseodymium compounds using the EDIXS methodology are presented. The measurements were performed at the Brazilian Synchrotron Light Source (LNLS, Campinas) using the typical 45°–45° geometry and an energy dispersive system (EDS). Spectra were analyzed by Principal Component Analysis (PCA). After the data processing using multivariate methods, the results show a clear discrimination of the different element compounds, being even possible an oxidation-state quantification procedure. The outcome is significant since this novel EDIXS tool allowed, for the first time, observing different species of rare earth elements by means of the inspection of a particular emitted L line. • A novel spectroscopic tool for chemical states determinations of rare earth and heavy elements is presented. • Some benefits over conventional absorption techniques are fast acquisition and low self-absorption avoiding energy scans. • EDIXS can be applied in several irradiation geometries and experimental setups. • This discrimination methodology is applied, for the first time, to the L absorption edge of lanthanides. • Quantification of oxidation states are attempted and discussed. [ABSTRACT FROM AUTHOR]

Cultural heritage artworks, and in particular paintings, are considered real treasures of humankind. This is why a proper characterization of a piece not only provides information regarding the artistic process of its conception but also a valuable tool for improving the conservation procedures. In this work Energy Dispersive Inelastic X-ray Scattering (EDIXS) spectroscopy with spatial resolution is used, for the first time, for the chemical-state characterization of copper-based paintings. The results show that this methodology can provide a new tool for the study of the chemical environment of an element under study present in a particular sample of interest in 2D (and even 3D) with even nanometric resolution. The EDIXS technique is presenting several advantages for this kind of studies, being of easy extension to several fields of cultural heritage research beyond paintings. [Display omitted] • A novel spectroscopic tool for chemical states determinations of paintings is presented. • Some benefits over conventional absorption techniques are fast acquisition and low self-absorption avoiding energy scans. • EDIXS can be applied in several irradiation geometries and experimental setups. • Spatially-resolved results at micrometer level are provided and discussed. • Applications using other X-ray sources and extension to several fields of cultural heritage are possible. [ABSTRACT FROM AUTHOR]

Remediation of heavy metal-contaminated water using phytoremediation with accumulator aquatic plants is a promising low-cost emerging technology that adapts very well to the surrounding ecosystem. For the system to work efficiently, metal-saturated plants must be replaced, producing a potentially toxic amount of biomass that is usually stored dry to reduce its volume. The speciation of the high metal content in this biomass is crucial to define its final destination. This work explores the application of synchrotron-based EDIXS (Energy Dispersive Inelastic X-ray Scattering) to monitor the speciation of copper in regional aquatic plants from a laboratory-scale phytoremediation system. The phytofiltration system utilized Lemna minor L. and Salvinia biloba Raddi species grown under controlled conditions of light and nutrient availability. Both species are known hyperaccumulators of copper and are prevalent in lakes and rivers across South America. The validation of EDIXS was previously carried out by comparing the results of copper standard samples with those obtained by XANES. The findings revealed that both plant species retained copper in chemical complexes exhibiting octahedral coordination with a Cu valence of 2. Notably, differences emerged between the leaves and roots of Lemna minor L., suggesting a more pronounced adsorption of copper in its leaves, a trend that intensified with exposure. In opposite, for Salvinia the differences between leaves and roots suggests the presence of specific protective mechanisms to cope the copper exposure. Surprisingly, no significant dependence on copper concentration of the aqueous media was observed for either species. These promising results endorse the viability of the proposed methodology in identifying the most effective fate of biomass generated in phytoremediation systems. EDIXS provides a valid tool for performing local copper speciation in aquatic plants with sufficient selectivity to identify subtle differences in various biological tissues. The simplicity of this methodology renders it a valuable tool for advancing our comprehension of metal speciation within waste biomass, thereby holding significant implications for the development of environmental remediation strategies. [Display omitted] • Study of Cu speciation in waste biomass from phytofiltration systems by EDIXS. • Thorough validation and interpretation of EDIXS findings supported by XANES. • Application to a phytofiltration system utilizing South American plant species. • Identification of Cu(II) complexes showing octahedral coordination. • Development of a simple methodology for monitoring metal speciation in waste biomass. [ABSTRACT FROM AUTHOR]