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We present in-situ studies of H loss from YHO films using ion beam analysis and its effect on the photochromic properties. The film evaporates loosely bound H under exposure to a beam of 3056 keV He2+ without a concomitant increase of O. Annealing at 145 °C decreases both the photochromic contrast and the bleaching speed indicating the importance of mobile H for the photochromic reaction. [ABSTRACT FROM AUTHOR]

The localisation and quantitative analysis of lithium (Li) in battery materials, components, and full cells are scientifically highly relevant, yet challenging tasks. The methodical developments of MeV ion beam analysis (IBA) presented here open up new possibilities for simultaneous elemental quantification and localisation of light and heavy elements in Li and other batteries. It describes the technical prerequisites and limitations of using IBA to analyse and solve current challenges with the example of Li-ion and solid-state battery-related research and development. Here, nuclear reaction analysis and Rutherford backscattering spectrometry can provide spatial resolutions down to 70 nm and 1% accuracy. To demonstrate the new insights to be gained by IBA, SiOx-containing graphite anodes are lithiated to six states-of-charge (SoC) between 0–50%. The quantitative Li depth profiling of the anodes shows a linear increase of the Li concentration with SoC and a match of injected and detected Li-ions. This unambiguously proofs the electrochemical activity of Si. Already at 50% SoC, we derive C/Li = 5.4 (< LiC6) when neglecting Si, proving a relevant uptake of Li by the 8 atom % Si (C/Si ≈ 9) in the anode with Li/Si ≤ 1.8 in this case. Extrapolations to full lithiation show a maximum of Li/Si = 1.04 ± 0.05. The analysis reveals all element concentrations are constant over the anode thickness of 44 µm, except for a ~6-µm-thick separator-side surface layer. Here, the Li and Si concentrations are a factor 1.23 higher compared to the bulk for all SoC, indicating preferential Li binding to SiOx. These insights are so far not accessible with conventional analysis methods and are a first important step towards in-depth knowledge of quantitative Li distributions on the component level and a further application of IBA in the battery community. [ABSTRACT FROM AUTHOR]

Direct observation of the lithiation and de-lithiation in lithium batteries on the component and microstructural scale is still difficult. This work presents recent advances in MeV ion-beam analysis, enabling quantitative contact-free analysis of the spatially-resolved lithium content and state-of-charge (SoC) in all-solid-state lithium batteries via 3 MeV proton-based characteristic x-ray and gamma-ray emission analysis. The analysis is demonstrated on cross-sections of ceramic and polymer all-solid-state cells with LLZO and MEEP/LIBOB solid electrolytes. Different SoC are measured ex-situ and one polymer-based operando cell is charged at 333 K during analysis. The data unambiguously show the migration of lithium upon charging. Quantitative lithium concentrations are obtained by taking the physical and material aspects of the mixed cathodes into account. This quantitative lithium determination as a function of SoC gives insight into irreversible degradation phenomena of all-solid-state batteries during the first cycles and locations of immobile lithium. The determined SoC matches the electrochemical characterization within uncertainties. The presented analysis method thus opens up a completely new access to the state-of-charge of battery cells not depending on electrochemical measurements. Automated beam scanning and data-analysis algorithms enable a 2D quantitative Li and SoC mapping on the μm-scale, not accessible with other methods. [ABSTRACT FROM AUTHOR]

Presented is a review of the accomplishments, of the light-element program, conducted at the Lund Ion-Beam Analysis Facility. A detailed account is given of the current experimental setup at the total Ion-Beam Analysis Chamber, which is equipped with two Double-Sided Silicon Strip Detectors for charge particle detection, a silicon drift detector for PIXE analysis, an electrostatic deflection system for charge measurement and implements a Nuclear Micro-Probe. A summary of the work conducted to date on the quantification of low Z elements is presented on a case by case basis. Details of the current work efforts and an overview of the advances which are intended in the near future are given. [ABSTRACT FROM AUTHOR]

The localisation and quantitative analysis of lithium (Li) in battery materials, components, and full cells are scientifically highly relevant, yet challenging tasks. The methodical developments of MeV ion beam analysis (IBA) presented here open up new possibilities for simultaneous elemental quantification and localisation of light and heavy elements in Li and other batteries. It describes the technical prerequisites and limitations of using IBA to analyse and solve current challenges with the example of Li-ion and solid-state battery-related research and development. Here, nuclear reaction analysis and Rutherford backscattering spectrometry can provide spatial resolutions down to 70 nm and 1% accuracy. To demonstrate the new insights to be gained by IBA, SiOx-containing graphite anodes are lithiated to six states-of-charge (SoC) between 0–50%. The quantitative Li depth profiling of the anodes shows a linear increase of the Li concentration with SoC and a match of injected and detected Li-ions. This unambiguously proofs the electrochemical activity of Si. Already at 50% SoC, we derive C/Li = 5.4 (< LiC6) when neglecting Si, proving a relevant uptake of Li by the 8 atom % Si (C/Si ≈ 9) in the anode with Li/Si ≤ 1.8 in this case. Extrapolations to full lithiation show a maximum of Li/Si = 1.04 ± 0.05. The analysis reveals all element concentrations are constant over the anode thickness of 44 µm, except for a ~6-µm-thick separator-side surface layer. Here, the Li and Si concentrations are a factor 1.23 higher compared to the bulk for all SoC, indicating preferential Li binding to SiOx. These insights are so far not accessible with conventional analysis methods and are a first important step towards in-depth knowledge of quantitative Li distributions on the component level and a further application of IBA in the battery community.

In many IBA applications the aim is to obtain quantitative figures characterising the sample, usually requiring a reliable measurement of the beam current for normalisation. To avoid the drawbacks associated with on-sample and post-sample charge measurement systems a pre-sample measurement system can be used. In this work an upgrade to the pre-sample charge measurement system at the Lund Ion-beam Analysis Facility is presented, in which a custom built control module based around a Teensy 3.2 micro-controller has been added to the existing system. The new control module allows for remote handling and monitoring of the deflection system, operated via USB connection to a PC running a graphical user interface. Details of the control modules functionality, design and programming are given, as well as the functionality of the user interface. An example of how the new control module can be used for automated calibration of the deflection system is also presented. [ABSTRACT FROM AUTHOR]

During the bombardment of insulator materials with high-energy particles, the samples are often emitting light and are sparking. This fact makes both the ion-beam analysis and the ion implantation of insulating materials more difficult. Light may disturb the detectors, sparks usually disturb the current-integration systems and electronics. Moreover, the accumulation of positive charges alters the results of the experiments via decelerating the incoming ions and accelerating the outgoing particles. In case of ion implantation, the projected range may be changed, while in ion-beam analysis the shape of the spectra can be changed resulting evaluation problems. To avoid the charge accumulation several methods have been used in the daily practice such as applying thin cover layers, wrapping or masking the samples, applying relatively low beam currents or electron sources in the experimental chamber. A short review of the above mentioned methods to avoid the charge accumulation is given. Moreover, the evaluation problems of the spectra taken on sparking (or at least charged-up) samples are also discussed. Proton and helium backscattering spectrometry as well as elastic recoil detection analysis are used to demonstrate the capability of a simple model of charge accumulation which is implemented to DEPTH code. [ABSTRACT FROM AUTHOR]

Direct observation of the lithiation and de-lithiation in lithium batteries on the component and microstructural scale is still difficult. This work presents recent advances in MeV ion-beam analysis, enabling quantitative contact-free analysis of the spatially-resolved lithium content and state-of-charge (SoC) in all-solid-state lithium batteries via 3 MeV proton-based characteristic x-ray and gamma-ray emission analysis. The analysis is demonstrated on cross-sections of ceramic and polymer all-solid-state cells with LLZO and MEEP/LIBOB solid electrolytes. Different SoC are measured ex-situ and one polymer-based operando cell is charged at 333 K during analysis. The data unambiguously show the migration of lithium upon charging. Quantitative lithium concentrations are obtained by taking the physical and material aspects of the mixed cathodes into account. This quantitative lithium determination as a function of SoC gives insight into irreversible degradation phenomena of all-solid-state batteries during the first cycles and locations of immobile lithium. The determined SoC matches the electrochemical characterization within uncertainties. The presented analysis method thus opens up a completely new access to the state-of-charge of battery cells not depending on electrochemical measurements. Automated beam scanning and data-analysis algorithms enable a 2D quantitative Li and SoC mapping on the µm-scale, not accessible with other methods.

The analysis of material composition by ion-beam analysis (IBA) is becoming a standard method, similar to electron microscopy. A pool of IBA methods exists, from which the combination of particle-induced-X-ray emission (PIXE), particle induced gamma-ray analysis (PIGE), nuclear-reaction-analysis (NRA), and Rutherford-backscattering-spectrometry (RBS) provides the most complete analysis over the whole periodic table in a single measurement. Yet, for a highly resolved and accurate IBA analysis, a sophisticated technical setup is required integrating the detectors, beam optics, and sample arrangement. A new end-station developed and installed in Forschungszentrum Jülich provides these capabilities in combination with high sample throughput and result accuracy. Mechanical tolerances limit the device accuracy to 3% for RBS. Continuous pumping enables 5 × 10−8 mbar base pressure with vibration amplitudes < 0.1 µm. The beam optics achieves a demagnification of 24–34, suitable for µ-beam analysis. An in-vacuum manipulator enables scanning 50 × 50 mm² sample areas with 10 nm accuracy. The setup features the above-mentioned IBA detectors, enabling a broad range of analysis applications such as the operando analysis of batteries or the post-mortem analysis of plasma-exposed samples with up to 3000 discrete points per day. Custom apertures and energy resolutions down to 11 keV enable separation of Fe and Cr in RBS. This work presents the technical solutions together with the quantification of these challenges and their success in the form of a technical reference.

Six carbon materials with potential application in research and development of battery electrodes were tested for mass fractions of more than 40 elements by instrumental neutron activation analysis and ion-beam methods. The results indicate potential of the methods for characterization of materials with very low content of impurities (carbon black) as well as those with relatively high content of certain transition metals (e.g., single walled carbon nanotubes, SWCNT). A batch-to-batch variability of elemental impurities was found for commercial SWCNT. Quality control was performed by analysis of CRM SWCNT-1, NIST SRM 1633b, NIST SRM 2711, and NIST SRM 1547. [ABSTRACT FROM AUTHOR]

Bismuth oxide thin films (250 nm) were deposited via unbalanced DC magnetron sputtering on Ti-6Al:4V, and common glass substrates. After being deposited, the films were heated (annealed) for 1 h between 473 and 1073 K in steps of 100 K. The morphology was characterized via scanning electron microscopy (SEM), the micro-structure was analyzed through x-ray diffraction (XRD), and the electrochemical behavior was analyzed with the potentiodynamic polarization test. Additionally, a proton-induced X-ray emission (PIXE) test was done on one of the samples in order to check the chemical distribution of the elements in the surface. The SEM and XRD analyses showed that the post-annealing process affects both the morphology and the structure of the films for all the samples. Finally, the electrochemical tests showed that films grown at 773 K have the highest degree of corrosion resistance. [ABSTRACT FROM AUTHOR]

Non-destructive microbeam-based methods were used for 2-D mapping of trace elements to gain a greater appreciation of otolith composition and spatial configuration. Based on studies of a wide variety of fish taxa, this approach more fully captures the nature of otolith chemical heterogeneity. Such variations may be due to a number of factors, including differences in crystallization, genetics, growth or even sample preparation or contamination. Examples presented here highlight research conducted at the Lund Ion Beam Analysis Facility (LIBAF) and at the Cornell High-Energy Synchrotron Source (CHESS). [ABSTRACT FROM AUTHOR]

A large variety of materials contain both carbon and oxygen atoms, in particular oxidized carbides, carbon alloys (as ZrC, UC, steels, etc.), and oxycarbide compounds (SiCO glasses, TiCO, etc.). Here a new ion beam analysis methodology is described which enables quantification of elemental composition and oxygen concentration profile over a few microns. It is based on two procedures. The first, relative to the experimental configuration relies on a specific detection setup which is original in that it enables the separation of the carbon and oxygen NRA signals. The second concerns the data analysis procedure i.e. the method for deriving the elemental composition from the particle energy spectrum. It is a generic algorithm and is here successfully applied to characterize an oxidized uranium carbide sample, developed as a potential fuel for generation IV nuclear reactors. Furthermore, a micro-beam was used to simultaneously determine the local elemental composition and oxygen concentration profiles over the first microns below the sample surface. This method is adapted to the determination of the composition of MCOcompounds with a sensitivity on elemental atomic concentrations around 1000 ppm. [ABSTRACT FROM AUTHOR]

Ion microbeam facilities are analytical tools with high spatial resolution exploiting MeV ion beams. The interactions of beam particles with atoms and nuclei of the target induce the emission of characteristic radiation, the energy of which provides signatures of the compositional and/or structural properties of the target; Ion-Beam Analysis (IBA) techniques, based on the detection of such radiation, enable characterisation of samples of interest, e.g. in material and earth sciences, cultural heritage, biology, medicine, and environmental studies. External beams, obtained by extracting the particles into the atmosphere through a thin window, have many attractive features, e.g. non-destructive/non-invasive analysis and ease of working, so many laboratories have dedicated beam-lines to ex-vacuo IBA analyses. External microprobes have made it possible to obtain probes in the micron range by adopting strong focusing lenses, ultra-thin windows for beam extraction, and short/ultra-short external path of beam particles in light gases; they have also made possible the use of new external IBA techniques, e.g. BS, ERDA, STIM, and IBIC. By adopting systems to raster scan the beam over the sample, imaging capabilities have also become available for ex-vacuo analysis. External scanning microprobes + IBA techniques have enabled the characterisation of samples with high spatial resolution, comparable with that achievable in-vacuum for thick samples, avoiding sample damage. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: The knowledge of the energy-loss distribution in a single ion-atom collision is a prerequisite for subnanometric resolution in depth-profiling techniques such as nuclear-reaction profiling (NRP) and medium energy ion-scattering (MEIS). The usual Gaussian approximation specified by the stopping power and energy straggling is not valid for near surface regions of solids, where subnanometric or monolayer resolution can be achieved. In this work we propose an analytical formula for the line shape to replace the usual Gaussian distribution widely used in low-resolution ion-beam analysis. Furthermore, we provide a simple physical method to derive the corresponding shape parameters. We also present a comparison with full coupled-channel calculations as well as with experimental data at nearly single collision conditions. [Copyright &y& Elsevier]

Abstract: Helium ion-implantation can be used to form a buried layer of nanoscale cavities in Ti. This offers the potential for diffusing dopant atoms of interest for biomedical applications, into a Ti surface. Disc specimens were taken from a He-implanted foil and a small spot in the centre was eroded to a different depth on each disc before treatment with synthetic biological fluid. IBA techniques (including RBS, NRA and PIXE) were used to determine the uptake of specific elements in two regions: the central eroded spot and the outer (un-eroded) region. The most significant effect was for oxygen. A small amount of prior erosion resulted in a threefold increase in the oxygen in both regions. Whereas, greater erosion caused a rapid reduction in the uptake in the centre, the strong enhancement in the outer region remained a striking feature. This provides convincing evidence that oxygen can move laterally over large distances through the nanoporous layer. [Copyright &y& Elsevier]

Abstract: The safe and long-term control of radioactive waste arising from nuclear power plants is one of the major challenges to the future use of nuclear energy. The evaluation of nuclear waste matrices relies on numerous conditions regarding the physico-chemical properties of the selected materials, such as resistance against oxidation or aqueous corrosion, stability in a radioactive environment, and ability to confine radioactive elements. Ion beams provide efficient tools for the evaluation of radwaste matrices since they allow to address three major issues: (i) the simulation of ion irradiation; (ii) the doping of the matrix with stable elements simulating the nuclei to be confined; and (iii) the characterization of the material by the use of nuclear microanalysis techniques. Illustrative examples are provided in the case of urania and zirconia. [Copyright &y& Elsevier]

The glasses of Ljubljana, related historically to the spread of glassworks in the Venetian style, were studied by a combined PIXE/PIGE method based on the in-air proton beam. The contribution of PIGE was determination of Na, Mg and Al oxides that provided (1) non-ambiguous characterization of the alkali and limestone component, (2) stable concentration evaluation algorithm relying on the normalization of all metal oxides to 100%. The majority of investigated samples form a compact group with small variations due to the alkalis used; a clear distinction from a few imported objects confirms local production. The raw materials in medieval glassworks differ significantly from those of Late Antiquity. [Copyright &y& Elsevier]

The influence of implantation dose on the oxidation behavior of AISI-321 stainless steel was investigated. The steel samples were implanted with Al+ ions of energy 40 keV (doses, 0.5 to 3×1017 ions/cm2) and oxidized in air at 650°C for 48 hr. For comparison purposes, samples were also implanted with a dose of 2×1017 ions/cm2 of energy 200 keV and treated in a similar way. Nuclear-reaction analysis (NRA) and Rutherford backscattering spectrometry (RBS) were used in order to investigate the oxidized samples and to determine the oxygen-depth distribution on the implanted samples. The depth distribution of the steel constituents was determined by secondary-ion mass spectroscopy (SIMS), whereas X-ray diffraction (XRD) was applied to the investigation of the formed oxide scales. The composition and the morphology of the modified region were examined by scanning electron microscopy (SEM-EDS). Al-implantation improves the oxidation resistance of the steel and affects the thermal behavior of the material depending on the implantation dose and energy. The influence of the implantation dose and energy are discussed and mechanisms to explain the experimental results are proposed. [ABSTRACT FROM AUTHOR]

The 24Mg(α, p)27 Al nuclear reaction was applied for the determination of the magnesium distribution in near-surface layers of materials. The cross sections of this reaction were determined in the energy region between 4.5 and 5.5 MeV in steps of 5 to 10 KeV (θlab : 158°) using thin magnesium films. The investigated projectile energy region included five main resonances allowing the determination of magnesium. The uncertainty of the cross-section determination was of the order of 7%. The applicability of the technique was tested using Mg-implanted AISI 321 steel samples. Depth resolution of 100 nm and detection limits of the order of 0.1 ppm were achieved for the determination of magnesium in steel samples using the 4805 keV resonance of the 24Mg(α, p)27 Al nuclear reaction. The shape and height of the magnesium depth-profile in the Mg-implanted steel samples were compared with corresponding values obtained by X-ray photoelectron spectroscopy. [ABSTRACT FROM AUTHOR]

AISI-321 steel samples were implanted with Al ions (implantation-energy:40 keV; dose: 2×1017 ions/cm2). Thermal oxidationof the samples was performed at 450, 550, 600, and 650°C for periodsvarying from 1 to 6 days in air and in a corrosive CO2-containingenvironment. Nuclear Reaction Analysis (NRA) and Rutherford BackscatteringSpectrometry (RBS) were used to investigate the oxidized samples. Asignificant improvement of the oxidation resistance of the implantedmaterial in comparison to the nonimplanted material was observed. Thisespecially applies for samples oxidized at high temperatures. The aluminumdepth distribution determined by NRA [using the resonance at 992 keV of the27Al(p, γ )28Si nuclear reaction] and RBS,indicated no variation of the Al profile in the temperature region450–600°C, whereas at 650°C a slight Al diffusion wasobserved. Scanning electron microscopy (SEM–EDS) was applied to studythe surface morphology and the constitution of the oxide scale formed, aswell as to explain the influence of Al implantation on the oxidation behaviorof AISI-321 austenitic stainless steel. [ABSTRACT FROM AUTHOR]

Many biomedical experiments require the qualitative and quantitative localization of trace elements with high sensitivity and good spatial resolution. The feasibility of measuring the chemical form of the elements, the time course of trace element metabolism, and conducting experiments in living biological systems are also important requirements for biological trace element research. Nuclear analytical techniques that employ ion or photon beams have grown in importance in the past decade and have led to several new experimental approaches. Some of the important features of these methods are reviewed here along with their role in trace element research. Examples of their use are given to illustrate potential for new research directions. It is emphasized that the effective application of these methods necessitates a closely integrated multidisciplinary scientific team. [ABSTRACT FROM AUTHOR]