TY - CONF A1 - Riedel, Jens T1 - Acoustic Ion Manipulation: Electric-field-free Approach to Gate, Focus, and Separate Ions at Atmospheric Pressure N2 - Approaches to control the motion and direction of ionized particles and mole-cules are an essential aspect of ion-based spectrometries, such as mass spec-trometry (MS) and ion mobility spectrometry (IMS). A wide variety of ion optics exist to reflect, focus, separate, gate, and filter ions based on physical proper-ties. Notably all rely on electric and magnetic fields to alter the trajectory of ionized atoms and molecules. While these optics are quite efficient at low pressures due to the large mean free path, diffusion and electrostatic repulsion between ions dominate at higher pressures. Conventional ion optics, that use electric or magnetic fields, can guide ions at atmospheric pressure (AP), but require high field strengths to overcome the dominating aerodynamic effects. Here, we describe a remarkable phenomenon whereby low-power acoustic fields are used to move, shape, gate, and separate beams of gaseous ions at atmospheric pressure. We refer to this approach as Acoustic Ion Manipulation (AIM). Gaseous ions at AP are directed towards and separated by the presence of the acoustic field. To better understand the phenomenon, an ion-detector array provided a measure of bulk ion movement, while mass spectrometry (MS) offered chemical-specific information. As one example of an AIM setup, a standing acoustic wave was formed with two ultrasonic speakers and placed between an ionization source and ion detector. Ion beams preferentially travel through regions of stable pressure gradients (i.e. nodes) and deflect from un-stable regions (i.e. antinodes). Shadowgraphy revealed that the ions are sepa-rated from a neutral gas stream. Specific examples of ion focusing, gating, and separation (based on ion size) will be shown. In addition, experimental findings will be used to postulate a theory to develop a better understand of the behav-ior of gas-phase ions in acoustic fields. This discovery could have profound im-pacts in IMS/MS instrumentation as well as materials processing and charac-terization. T2 - 56. Jahrestagung der DGMS CY - Göttingen, Germany DA - 04.03.2025 KW - Acoustic Ion Manipulation KW - Mass spectrometry KW - Ultrasound PY - 2025 AN - OPUS4-64208 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schröter, Felix T1 - Fluorescence? Not on my Shift! Excitation- Shifted UV Raman Microspectroscopy N2 - Spectroscopic analysis of samples provides elemental information, which is useful when the sample is homogenous. But many samples are not and consequently the creation of maps detailing the spatial composition of materials is needed. Raman microscopy can be used for this exact purpose but suffers a big drawback. The inherently weak Raman scattering results in long measurement times, especially when maps with many data points are created. This is due to the long exposure times needed when visible light lasers are used. A shift to UV-Lasers significantly increases the Raman intensity, as it scales with the fourth power of the inverse of the laser wavelength. But UV excitation often leads to fluorescence which can obscure the relatively weak Raman signal. Consequently, UV-Raman can only be used with specially prepared samples, for example through photo-bleaching, or with samples producing no fluorescence background in the measurement region. A solution is proposed that uses shifted-excitation Raman difference spectroscopy (SERDS) in a confocal microscope to obtain fluorescence-free Raman spectra. This is possible due to the collection of two Raman spectra at different excitation wavelengths. SERDS then allows for the calculation of just the Raman signal from the difference spectrum, which eliminates any fluorescence backgrounds, as they are not excitation wavelength dependent. The presented approach employs a polarized beamsplitter to irradiate the same spot with two lasers of different wavelengths which share the same beam path in the microscope. Consequently, a SERDS UV Raman Microscope is created, which utilizes the speed of UV-Raman without the drawbacks of possible broad fluorescence backgrounds. Here we present the instruments methodology and some first results. T2 - ANAKON 2025 CY - Leipzig, Germany DA - 10.03.2025 KW - UV Raman Spectroscopy KW - UV Raman Microspectroscopy KW - Confocal Microscopy KW - Excitation-Shifted Raman Spectroscopy PY - 2025 AN - OPUS4-62734 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Blume, Simon T1 - Exploiting Lithium Self-Absorption in a Laser-Induced Breakdown Plasma for Isotopic Analysis via Spatial Heterodyne Spectroscopy N2 - Lithium-ion batteries are ubiquitous in modern life. From powering consumer electronics to enabling electric mobility and energy storage, they are a key building block of a sustainable future. Determination of the ratio of the two naturally abundant stable isotopes, 7Li and 6Li, provides access to a wide variety of information, such as studying the aging processes of lithium-ion batteries or elucidating the isotopic fingerprinting of natural or recycled sources of lithium. However, accurately measuring the lithium isotope ratio in complex samples remains challenging, often requiring either extensive sample pretreatment or specialized equipment, thus impeding in-situ and high-throughput demands of global industries. Recognition and determination of the individual lithium isotopes with conventional laser-induced breakdown spectroscopy (LIBS) setups is nearly impossible. While LIBS offers several advantages, such as obviating time- and resource-intensive sample preparation and enabling rapid measurements, the high temperature (~20,000 K) of the plasma, as well as the Stark-broadening caused by the nascent free electrons spectrally broaden the atomic emission lines to such an extent that the isotopic shift of the lithium doublet at 670 nm cannot be resolved. Since, the excited state energy for this transition amounts to only 14,900 cm-1, lithium exhibits a pronounced self-absorption dip in the emission signal. This self-absorption dip is significantly less affected by the broadening effects, therefore, allowing for the resolution of the isotopic shift from its line shape. Spatial heterodyne spectroscopy (SHS) offers the superior resolution capabilities necessary to differentiate the individual isotopic contributions. To address the generally limited sensitivity of SHS, a high-repetition-rate (>10 kHz) laser allows the accumulation of more than 10,000 lasing events per spectral recording for a sufficient signal-to-noise ratio and gain statistical validity. Optical lithium fluoride serves as a model sample to showcase the analytical performance. Additionally, the impact of the laser parameters on the self-absorption will also be discussed. T2 - ANAKON 2025 CY - Leipzig, Germany DA - 10.03.2025 KW - Isotopic Analysis KW - Spatial Heterodyne Spectroscopy PY - 2025 AN - OPUS4-63559 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - You, Yi T1 - Advanced Repetition-Rate Modulation and Computational Strategies for Background-Free LIBS Using Non-Gated Spectrometers N2 - Laser-induced breakdown spectroscopy (LIBS) is recognized for its rapid, direct elemental analysis capabilities. However, its general adoption is constrained by the reliance on expensive, high-power consumption, gated cameras such as intensified charge-coupled devices (CCDs). These devices, while sensitive, are expensive and possess low frame rates, limiting their efficacy in dynamic or challenging environments. Our study proposes an innovative approach that leverages non-gated spectrometers in conjunction with the framework of correlation spectroscopy to isolate analyte signals responsive to a specific repetition-rate modulation pattern, thereby yielding spectra with zero background. We utilized a diode-pumped solid-state laser, with repetition rates ranging from 10 Hz to 30 kHz, to induce plasma in aqueous solutions containing various alkaline and earth-alkaline metals. With a non-gated single-grating linear CCD spectrometer, we found that the continuum signal plateaued at approximately 7 kHz. In contrast, atomic emissions from the dissolved analytes showed continued increases. Notably, atomic emissions from the solvent (water) were observable only above 8.5 kHz, at a significant high rate of increase. Through computational synthesis of a modulation pattern, we determined an optimized scheme that effectively discriminates continuum and analyte signals; this pattern was optimized with a genetic algorithm. The spectral matrix correlating signal intensity with laser repetition rate and wavelength was used as the input of the model. Meanwhile, the fitness function that extracts the background-free spectra was built in-house and inspired by the Gardner transform, which exploits the power of Fourier transform, allowing for flagging and splitting analyte signal from other undesired features. This approach bypasses the limitations associated with gated cameras, while providing a cost-effective alternative for robust LIBS applications. This advancement is particularly relevant in field, portable and remote applications, aligning with the ongoing demand for accessible, high-performance analytical tools in diverse scientific fields. T2 - SCIX 2024 Conference CY - Raleigh, NC, USA DA - 20.10.2024 KW - LIBS KW - Data Processing KW - High Repetition Rate KW - Repetition Rate Modulation KW - Data-Oriented Experimental Design PY - 2024 AN - OPUS4-62137 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Danischewski, Julia L. A1 - You, Yi A1 - Bauer, Lauren A1 - Riedel, Jens A1 - Shelley, Jacob T. T1 - Use of Resonant Acoustic Fields as Atmospheric-Pressure Ion Gates N2 - Ion optics are crucial for spectrometric methods such as mass spectrometry (MS) and ion mobility spectrometry (IMS). Among the wide selection of ion optics, temporal ion gates are of particular importance for time-of-flight MS (TOF-MS) and drift-tube IMS. Commonly implemented as electrostatic ion gates, these optics offer a rapid, efficient means to block ion beams and form discrete ion packets for subsequent analysis. Unfortunately, these devices rely on pulsed high voltage sources and are not fully transparent, even in their open state, which can lead to ion losses and contamination. Here, a novel atmospheric-pressure ion gate based on a resonant acoustic field structure is described. This effect was accomplished through the formation of a resonant, standing acoustic wave of alternating nodes and antinodes. Alignment of an atmospheric-pressure gaseous ion beam with an antinode, i.e. a region of transient pressure, of the acoustic structure acted as a gate and blocked ions from impinging on ion-selective detectors, such as a mass spectrometer and a Faraday plate. The velocity of the ion stream and acoustic power were found to be critical parameters for gating efficiency. In the presence of an acoustic field (i.e., a closed gate), ion signals decreased by as much as 99.8% with a response time faster than the readout of the ion-measurement devices used here (ca. 75 ms). This work demonstrates the basis for a low-cost, acoustic ion gate, which is optically transparent and easily constructed with low-power, off-the-shelf components, that could potentially be used with MS and IMS instrumentation. KW - Acoustic Ion Manipulation PY - 2025 DO - https://doi.org/10.1021/acs.analchem.4c05493 SN - 1520-6882 VL - 97 IS - 5 SP - 2890 EP - 2898 PB - American Chemical Society AN - OPUS4-62648 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Blume, Simon T1 - Femtosecond Laser-induced XUV Spectroscopy (LIXS) for Elemental Analysis N2 - In a typical laser-induced breakdown spectroscopy (LIBS) setup, emissions from collisional excitation of the atoms in the later stages of the plasma are detected and provide information about the elemental fingerprint of the sample. However, precise measurements, in particular quantification efforts, suffer from fluctuations of the intensity of the detected emission lines due to matrix effects and plasma-flicker noise, as well as significant background noise. In contrast, the early stages of the plasma are dominated by electron-ion recombination and Bremsstrahlung, which lead to sharp and intense x-ray emissions with consistent intensity profiles between laser pulses and suppressed background noise, therefore improving the limit of detection, especially for lighter elements. These emissions are detected in laser-induced XUV spectroscopy (LIXS).[1] Introduction of a femtosecond laser (pulse length ~100 fs) to the LIXS setup fundamentally changes the laser energy absorption and ablation process. The laser pulse energy is absorbed and redistributed by multiphoton absorption and inverse Bremsstrahlung and operates on a time frame faster than the plasma formation. Additionally, the plasma formation itself is accelerated leading to signal generation in the XUV-range before generation of the undesired background emissions. Thus, utilization of a femtosecond laser allows for further suppression of broadband emissions from the plasma allowing for sharper separation of the emission lines and improved limit of detection. This work presents the results of the combination of a LIXS setup with a femtosecond laser and assess the capabilities of this system with a model sample of cathode material from a spent lithium-ion battery. T2 - AMACEE 2025 CY - Brno, Czech Republic DA - 26.8.2025 KW - LIXS KW - Femtosecond laser KW - Instrumentation PY - 2025 AN - OPUS4-64118 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Palásti, Dávid jenö T1 - Interferometric sensing in the UV range – Investigation and comparison of the all-reflective spatial heterodyne spectrometer designs N2 - Spatial heterodyne spectrometers (SHS) are optical interferometric devices, working in the UV and visible spectral ranges [1]. The most common SHS setup is similar to the Michelson interferometer, both utilizes a beam splitter in the incoming beam path. In case of the SHS the split beams are not aimed towards orthogonal mirrors, but reflective optical gratings, set under a selected angle. These optical gratings diffract the beams, the direction of every wavelength will depend on the grating constant and the angle of the gratings. The wavefronts belonging to different wavelengths are going to cross each other under a unique angle, resulting in a spatial interference, which is recorded by a digital camera. This relatively compact setup provides high resolution and light throughput, which properties were harnessed for tasks requiring good line separation and/or high sensitivity [2]. However, SHS are only applicable on wavelengths for which an adequate transmissive beam splitter is available like the visible range, but not the far UV. To overcome this limitation, different all-reflective designs were introduced [3]. These instruments utilize symmetric optical gratings for the splitting and recombination of the beams. Although these SHS devices solve the main limitations of the traditional ones, they come with their fair share of drawbacks as well, such as more complex arrangement and the requirement for more delicate tuning. The behaviour of the traditional SHS is well documented [4,5], but in regards of the all-reflective ones we have much less available information. In this current study we utilized computational modelling to predict the behaviour of the all-reflective SH spectrometers, with special attention to the effects of the different alignment errors. Later we utilize this knowledge to fine tune an SHS for sensing (LIBS, Raman) in the UV region. Furthermore, we are introducing two new all-reflective SHS setups and compering them to their older counterparts. T2 - ANAKON 2025 CY - Leipzig, Germany DA - 10.03.2025 KW - SHS KW - Spectroscopy PY - 2025 AN - OPUS4-63556 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Blume, Simon T1 - Isotopic analysis of lithium via acousto-optically gated high-repetition laser-induced breakdown spectroscopy and spatial heterodyne spectroscopy N2 - Acousto-optically gating the emission signal from a laser-induced breakdown spectroscopy (LIBS) plasma negates some of the line-broadening effects, therefore, improving the signal line shape. However, the remaining influences disallow the differentiation of the contributions of the individual lithium isotopes, even when utilizing a high-resolution spatial heterodyne spectrometer (SHS). Nevertheless, isotopic analysis of lithium with LIBS is still feasible, because lithium exhibits a strong self-absorption dip in the emission signal, which is likewise characterized by the isotopic shift and even benefits from the broad emission lines typically observed in LIBS. The isotopic ration can be resolved from the absorption dip via high-resolution SHS. T2 - SciX 2024 CY - Raleigh, NC, USA DA - 20.10.2024 KW - LIBS KW - SHS KW - Isotopic analysis KW - Lithium PY - 2024 AN - OPUS4-62012 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Palásti, Dávid jenö T1 - The effects of the laser pulse profile on the plasma emission properties N2 - Intense laser pulses create plasmas upon radiation on targets, and the properties of such plasmas are generally determined by both the properties of the target and the laser pulse. In terms of laser intensity, the irradiance and even more importantly the fluence are the critical parameters [1]. Since most lasers emit pulses of a constant pulse duration dictated by the design of the resonator and Q-switch, these two parameters are usually used interchangeably in studies. However, with the emergence of fiber laser based light sources [2], which are capable not just to freely tune the pulse duration, but to generate variable and high pulse repetition rates, up to the MHz range, a new and interesting optimization aspect is given to the laser spectroscopy community. In our study a low alloy steel standard sample (BAS 403/1) was investigated using a variable pulse duration and pulse repetition rate MOPA laser with 80W power of  = 1064 nm emission (JPT M7, VONJAN Technology GmbH, Wessling, Germany). In our experiments the laser was set to pulses with low individual energy (0.4 mJ) at 200 kHz pulse repetition rate, while the pulse duration was varied between 50 and 500 ns. The plasma emission was recorded by an LTB Demon spectrometer in several spectral regions, which included iron, chromium and manganese lines. Utilizing the variable pulse duration of this laser source, it was possible to assess the effects of changing the fluence, while the irradiance was kept at the same value. Among the investigated parameters are the emission intensity, peak width and self-absorption characteristics of major and minor components, as well as the plasma temperature. While the effects for the peak intensity are quite well correlated with the fluence, its interplay with other peak parameters appear to be more complicated. T2 - AMACEE 2025 CY - Brno, Czech Republic DA - 26.08.2025 KW - LIBS KW - Fiberlaser KW - Plasma properties PY - 2025 AN - OPUS4-64218 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Onyenso, Gabriel A1 - AI-Zawity, Jiwar A1 - Farahbakhsh, Nastaran A1 - Schardt, Annika A1 - Yadigarli, Aydan A1 - Vakamulla Raghu, Swathi Naidu A1 - Engelhard, Carsten A1 - Müller, Mareike A1 - Schönherr, Holger A1 - Killian, Manuela S. T1 - Novel Ag-modified zirconia nanomaterials with antibacterial activity N2 - The outcome of an implant procedure largely depends on the implant's surface properties. Biomaterials are now designed to have surfaces with multifunctionality, such as favorable tissue integration and the ability to combat bacterial adhesion and colonization. Herein, we report on a simple approach to improve the antibacterial properties of zirconia nanotubes (ZrNTs) coatings by decorating with silver nanoparticles (AgNP), achieved through electrochemical anodization of a zirconium–silver alloy (Zr–Ag). The AgNPs were shown to partially consist of Ag2O, potentially enhancing the availability of Ag+ ions for antibacterial activity. The modified ZrNTs were characterized using SEM, EDS, ToF-SIMS, and XPS to determine their structural morphology and chemical composition, and were further subjected to antibacterial testing. The silver and zirconium ion release behavior was monitored via ICP-MS. ZrNTs decorated with AgNP exhibit strong antimicrobial activity (>99% bacterial killing) against both S. aureus and E. coli. Antimicrobial tests indicate that the antibacterial activity against the Gram-positive pathogen S. aureus was improved by a factor of 100 compared to unmodified ZrNTs, while unmodified ZrNTs already showed a comparable reduction of viable Gram-negative E. coli. This strategy illustrates a straightforward and effective modification that optimizes the interface between the host environment and the biomaterial surface to meet the very important criteria of biocompatibility and active antibacterial response. KW - Mass Spectrometry KW - Nanoparticles KW - Advanced Materials KW - ICP-MS KW - Antimicrobial material KW - ToF-SIMS PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653990 DO - https://doi.org/10.1039/d5ra07099f SN - 2046-2069 VL - 16 IS - 3 SP - 2286 EP - 2297 PB - Royal Society of Chemistry (RSC) AN - OPUS4-65399 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -