TY - JOUR
A1 - Durlo Tambara, Luís Urbano
A1 - Nikoonasab, Ali
A1 - Radtke, Martin
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Gluth, Gregor
T1 - Determination of the oxidation depths of ground granulated blast furnace slag-containing cement pastes using Mn K-edge X-ray absorption near-edge structure spectroscopy
N2 - The redox potential of the pore solution of hardened cements containing ground granulated blast furnace slag (GGBFS) affects reinforcement corrosion and immobilization of radioactive waste. Here, Mn K-edge X-ray absorption near-edge structure (XANES) spectroscopy was applied to determine the depth profile of the oxidation state of manganese in hardened GGBFS-containing cement pastes. Manganese was oxidized in the outer regions of some of the pastes, but the depth to which this occurred was not identical with the ‘blue-green/white color change front’, usually interpreted as indicating oxidation of sulfur species. For CEM III/B, the color change of the material was gradual and thus unsuitable for a precise determination of the oxidation depth, while for the alkali-activated slag, a distinct color change front was found, but full oxidation of manganese and sulfur had not occurred in the brighter region. Mn K-edge XANES spectroscopy is thus a more reliable method than the determination of the visual color change front to follow the ingress of the oxidation front.
KW - Manganese
KW - Oxidation
KW - Sulfide
KW - Alkali-activated materials
KW - Redox conditions
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-651469
DO - https://doi.org/10.1111/jace.70445
SN - 0002-7820
SN - 1551-2916
VL - 109
IS - 1
SP - 1
EP - 11
PB - Wiley
CY - Oxford
AN - OPUS4-65146
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pavlidis, Sotirios
A1 - Fischer, Eric W.
A1 - Opis-Basilio, Amanda
A1 - Bera, Ayan
A1 - Guilherme Buzanich, Ana
A1 - Álvarez-Sánchez, María
A1 - Wittek, Severin
A1 - Emmerling, Franziska
A1 - Ray, Kallol
A1 - Roemelt, Michael
A1 - Abbenseth, Josh
T1 - Ambiphilic Reactivity and Switchable Methyl Transfer at a T-Shaped Bi(NNN) Complex Enabled by a Redox-Active Pincer Ligand
N2 - We report the transition-metal-like reactivity of a geometrically constrained, ambiphilic bismuth(III) trisamide. Planarization of the Bi(III) center unlocks Bi−C bond formation when reacted with mild electrophiles (alkyl iodides and triflates) accompanied by two-electron oxidation of the utilized NNN pincer nligand. The preservation of the bismuth oxidation state is confirmed by single-crystal X-ray diffraction and X-ray absorption spectroscopy and corroborated by theoretical calculations. Sequential reduction of the oxidized ligand framework alters the reactivity of a generated Bi−Me unit, enabling controlled access to methyl cation, radical, and anion equivalents. The full [Bi(Me)(NNN)]+/•/− redox series was comprehensively characterized using NMR and EPR spectroscopy as well as spectro-electrochemistry. This work represents the first example of ligand-assisted, redox-neutral C−X bond splitting at bismuth, establishing a new paradigm for synthetic bismuth chemistry.
KW - Pincer ligand
KW - XAS
KW - Redox
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654948
DO - https://doi.org/10.1021/jacs.5c18955
SN - 0002-7863
VL - 148
IS - 2
SP - 2683
EP - 2692
PB - American Chemical Society (ACS)
AN - OPUS4-65494
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Hickel, Tilmann
A1 - Waske, Anja
A1 - Tehranchi, Ali
A1 - Bhattacharya, Biswajit
A1 - Stawski, Tomasz M.
A1 - Fellinger, Tim-Patrick
A1 - Mehmood, Asad
A1 - Witt, Julia
A1 - Ozcan, Ozlem
A1 - Guilherme Buzanich, Ana
A1 - Kumar, Sourabh
A1 - Mishra, Rajesh Kumar
A1 - Holzer, Marco
A1 - Stucchi de Camargo, Andrea Simone
A1 - Agudo Jácome, Leonardo
A1 - Manzoni, Anna
A1 - Fantin, Andrea
A1 - John, Elisabeth
A1 - Hodoroaba, Vasile-Dan
A1 - Bührig, Sophia
A1 - Murugan, Jegatheesan
A1 - Marschall, Niklas
A1 - George, Janine
A1 - Darvishi Kamachali, Reza
A1 - Maaß, Robert
A1 - Emmerling, Franziska
T1 - Chemically complex materials enable sustainable high-performance materials
N2 - Chemically complex materials (CCMats) including high-entropy alloys, oxides, and related multi-principal element systems offer a paradigm shift in materials design by leveraging chemical diversity to simultaneously optimize functional, structural, and sustainability criteria. The vastness of the compositional and structural space in CCMats propels the field into an expanding exploratory state. To reconcile functional and structural performance across this immense parameter space remains an open challenge. This Perspective evaluates the opportunities and challenges associated with harnessing chemical complexity across a broad spectrum of applications, such as hydrogen storage, ionic conductors, catalysis, magnetics, dielectrics, semiconductors, optical materials, and multifunctional structural systems. It is delineated how three central design strategies: targeted substitution (SUB), defect engineering (DEF), and diversity management (DIV) enable the reconciliation of high functional performance with long-term structural stability and environmental responsibility.
Advances in computational thermodynamics, microstructure simulations, machine learning, and multimodal characterization are accelerating the exploration and optimization of CCMats, while robust data infrastructures and automated synthesis workflows are emerging as essential tools for navigating their complex compositional space. By fostering cross-disciplinary knowledge transfer and embracing data-driven design, CCMats are poised to deliver next-generation materials solutions that address urgent technological, energy, and
environmental demands.
KW - Chemically complex materials
KW - Structural stability
KW - Functional performance
KW - Design strategies
KW - Sustainability
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655598
UR - https://www.sciencedirect.com/science/article/pii/S1359028626000033?via%3Dihub
DO - https://doi.org/10.1016/j.cossms.2026.101256
SN - 1359-0286
VL - 42
SP - 1
EP - 26
PB - Elsevier Ltd.
CY - Amsterdam
AN - OPUS4-65559
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - de Oliveira Guilherme Buzanich, Ana
T1 - Bridging Structure and Electronic State: Real-time XES–XRD Fusion for Functional Alloys
N2 - We present a unified X-ray Emission Spectroscopy (XES) and X-ray Diffraction (XRD) approach for real-time, in situ characterization of materials, demonstrated on Co₂FeSi Heusler alloys under varied heat treatments. The combination of XES and XRD is particularly well-suited to Heusler alloys, where subtle changes in atomic ordering and electronic structure (e.g. site occupancy, hybridization, and spin state) are tightly interdependent and critical for their magnetic and transport properties. In addition, this method enables more efficient materials design by reducing experimental iterations through comprehensive structural and electronic analysis. Developed at the mySpot beamline at BESSY-II, the platform integrates (a) digital twin-based experiment planning, (b) open-source XES spectral simulations, (c) an optimized single-shot, two-element XES setup with sub-pixel resolution for enhanced energy precision, and (d) result-driven beamtime utilization. With an unprecedented synchronized XES-XRD platform, we aim to shed light on how diffusion-controlled processes in Heusler alloys and double perovskites at elevated temperatures establish the formation of specific phases with distinct structure types in real time. This, in turn, strongly impacts the functional properties of the materials under scrutiny.
T2 - XLIV Colloquium Spectroscopicum Internationale
CY - Ulm, Germany
DA - 27.07.2025
KW - Multimodal
KW - X-ray spectroscopy
KW - X-ray diffraction
KW - Functional alloys
PY - 2025
AN - OPUS4-63991
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Cakir, Cafer Tufan
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Radtke, Martin
T1 - A Digital Twin Workflow for Optimizing X-ray Emission Spectroscopy (XES) Parameters in Material Science
N2 - In this contribution, I present a digital twin-based workflow designed to optimize experimental parameters in X-ray emission spectroscopy (XES), with a focus on reproducibility, data integration, and alignment with FAIR (Findable, Accessible, Interoperable, Reusable) principles in materials science and engineering (MSE). The developed pipeline begins with automated retrieval of crystallographic information from the Materials Project database based on a given sample composition. This structural data is then used to simulate the corresponding XES spectra using FDMNES, allowing for accurate prediction of element-specific emission lines.
The simulated emission lines are fed into an X-ray tracing (XRT) module, which builds a virtual replica of the experimental setup. This digital twin environment enables predictive modeling of spectrometer performance based on geometric configurations. The optimization focuses on two key parameters: the choice of the analyzing crystal and the distance between the sample and crystal (which also defines the crystal–detector distance due to Bragg condition constraints). An active learning algorithm is employed to iteratively adjust these parameters in order to achieve a desired energy-per-pixel (E/pixel) resolution with minimal intensity loss, enabling efficient, data-driven experimental planning.
By integrating data-driven simulations with real-time optimization strategies, this workflow supports efficient experiment planning while minimizing resource consumption and human error. Furthermore, all stages of the process—from data collection and simulation to optimization and visualization—are structured to ensure traceability and interoperability, facilitating future reuse and collaborative research.
I hope this contribution aligns well with the topic “Workflows for FAIR MSE Data” and offers a concrete example of how digital twins can be harnessed to improve the design, execution, and documentation of spectroscopy experiments in the MSE domain.
T2 - Opportunities and Challenges of FAIR Data at Photon and Neutron Facilities
CY - Bad Honnef, Germany
DA - 12.10.2025
KW - Digital-Twin
KW - XES
KW - Optimization
KW - Machine Learning
PY - 2025
AN - OPUS4-64676
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - INPR
A1 - Liu, Yanchen
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Alippi, Paola
A1 - Lee, Kug-Seung
A1 - Jeon, Taeyeol
A1 - Weißer, Kilian
A1 - Karlsen, Martin A.
A1 - Russo, Patrícia A.
A1 - Pinna, Nicola
T1 - FeNb2O6 as a high-performance anode for sodium-ion batteries enabled by structural amorphization coupled with NbO6 local ordering.
N2 - Pseudocapacitance-type transition metal oxides have been extensively investigated as anodes materials for lithium-ion batteries. Currently, they are also emerging as promising anodes for sodium-ion batteries due to their low volume change and safety. However, the potential electrochemical performance in sodium energy storage is not fully achieved, primarily due to the larger radius of the Na+-ions. Here, we report for the first time an iron niobate with columbite structure as a high-performance sodium storage anode. The presence of iron in the structure is vital to trigger the loss of long-range order through disorder of the FeO6 octahedra local structure, subsequently allowing reversible Na storage in an amorphous phase. Simultaneously, the formation of short-range ordered zigzag-chain structures within the NbO6 planes creates a “skeleton” that offers abundant active sites for pseudocapacitive ion storage and enhanced ion diffusion pathways. These characteristics of FeNb2O6 make it an effective intercalation host, offering high capacity along with fast Na+ insertion and extraction, as demonstrated through operando and ex-situ characterizations. It leads to an applicable reversible capacity ( 300 mAh g-1) with a favorable average voltage of ca. 0.6 V and excellent rate capability (180.4 mAh g-1 at a current density of 2 A g-1). This study provides insights into the development of intrinsically active transition metal oxides for Na+-ion intercalation.
KW - XAS
KW - Sodium-Ion-Batteries
KW - In-situ
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-631159
DO - https://doi.org/10.26434/chemrxiv-2025-2gn7z
SP - 1
EP - 51
PB - American Chemical Society (ACS)
AN - OPUS4-63115
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - de Oliveira Guilherme Buzanich, Ana
T1 - The versatility of XAS@BAM for real-time in situ electrocatalysis in collaborative materials research
N2 - With the global push toward sustainable energy technologies, the development of efficient and durable electrocatalysts has become a research priority. Real-time in situ studies are essential to understand the dynamic behavior of catalysts under operational conditions. X-ray absorption spectroscopy (XAS) offers a unique, element-specific probe of electronic and structural changes at the active sites of electrocatalysts during electrochemical reactions.
At BAM, collaborative research efforts leverage the advanced capabilities of the BAMline at the Berlin Synchrotron BESSY-II to study electrocatalytic materials under realistic working conditions. As a dedicated materials research beamline, the BAMline enables in situ and operando XAS across different time and length scales, making it ideally suited for monitoring catalytic transformations in real time.
This presentation highlights the analytical strengths and sample environments developed for electrochemical cells at BAM, showcasing their application to electrocatalysis for energy conversion (e.g., water splitting, CO₂ reduction). Emphasis will be placed on how these insights contribute to the rational design and real-time optimization of functional materials for a sustainable energy future.
T2 - MATSUS Konferenz
CY - Valencia, Spanien
DA - 20.10.2025
KW - Operando
KW - XAS
KW - In situ
KW - Electrocatalysis
PY - 2025
AN - OPUS4-64493
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Yun, Tae Gyu
A1 - Chen, Boqiang
A1 - Wells, Sarah
A1 - Lim, Younghwan
A1 - Kim, Jun Seop
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Radtke, Martin
A1 - Waegele, Matthias M.
A1 - Risch, Marcel
A1 - Grimaud, Alexis
ED - de Oliveira Guilherme Buzanich, Ana
T1 - Extrinsic and Intrinsic Factors Governing the Electrochemical Oxidation of Propylene in Aqueous Solutions
N2 - The electrochemical synthesis of commoditychemicals such as epoxides and glycols offers a sustainablealternative to conventional methods that involve hazardouschemicals. Efforts to improve the yield and selectivity of propyleneoxidation using Pd-based catalysts have been shown to be highlysensitive to applied potential, pH, and electrochemical cell design.Record efficiencies and yields were obtained by substitution ofPdO by 4d or 5d transition metals, including Pt, with thus far littlerationale regarding the origin for the improvement. Throughelectrochemical analysis, scanning transmission electron micros-copy, X-ray absorption spectroscopy, and surface-enhanced infraredabsorption spectroscopy, we investigated the mechanism ofpropylene oxidation on Pd-based catalysts. We demonstrate thatadsorbates forming on PdO, where Pd adopts a square-planar coordination [PdO4], differ from that forming on the surface ofoxidized metallic Pd catalysts with an oxo intermediate mediating propylene oxidation on PdO. We further show that Pt substitutionin PdO does not modify this oxo intermediate. Varying pH, we found that the onset for propylene oxidation is pH independent,indicating a potential-determining step where the proton is not involved in and similar reaction pathway in acidic and near-neutralconditions. Finally, our work undoubtedly demonstrates that high Faradaic efficiency toward propylene glycol and propylene oxideformation, such as those previously reported in the literature, can be achieved by means of electrode engineering and mastery ofmass transport and local pH. Notably, we achieved ≈100% faradaic efficiency for propylene glycol at 1.7 V vs RHE in acidic mediausing a Pt-substituted PdO catalyst loaded onto a gas diffusion electrode.
KW - XAS
KW - Electrochemistry
KW - Popylene oxidation
KW - 4d metals
PY - 2025
DO - https://doi.org/10.1021/jacs.5c02585
SN - 0002-7863
VL - 147
IS - 14
SP - 12318
EP - 12330
PB - American Chemical Society (ACS)
AN - OPUS4-63112
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Liu, Yanchen
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Montoro, Luciano A.
A1 - Liu, Hao
A1 - Liu, Ye
A1 - Emmerling, Franziska
A1 - Russo, Patrícia A.
A1 - Pinna, Nicola
T1 - A partially disordered crystallographic shear block structure as fast-charging negative electrode material for lithium-ion batteries
N2 - A well-ordered crystalline structure is crucial in battery electrodes, as the dimensionality and connectivity of the interstitial sites inherently influence Li+ ions diffusion kinetics. Niobium tungsten oxides block structures, composed of ReO3-type blocks of specific sizes with well-defined metal sites, are promising fast-charging negative electrode materials. Structural disorder is generally detrimental to conductivity or ion transport. However, here, we report an anomalous partially disordered Nb12WO33 structure that significantly enhances Li-ion storage performance compared to the known monoclinic Nb12WO33 phase. The partially disordered phase consists of corner-shared NbO6 octahedra blocks of varied sizes, including 5×4, 4×4, and 4×3, with a disordered arrangement of distorted WO4 tetrahedra at the corners of the blocks. This structural arrangement is robust during lithiation/delithiation, exhibiting minor local structure changes during cycling. It enables accelerated Li-ion migration, resulting in promising fast-charging performance, namely, 62.5 % and 44.7 % capacity retention at 20 C and 80 C, respectively. This study highlights the benefits of introducing disorder into niobium tungsten oxide shear structures, through the establishment of clear structure-performance correlations, offering guidelines for designing materials with targeted properties.
KW - Lithium ion batteries
KW - Oxides
KW - XANES
KW - XRD
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-637994
DO - https://doi.org/10.1038/s41467-025-61646-9
SN - 2041-1723
VL - 16
IS - 1
SP - 1
EP - 15
PB - Springer Science and Business Media LLC
AN - OPUS4-63799
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pessanha, Sofia
A1 - Fortes, António
A1 - Lopes, Marta B.
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Ortega-Feliu, Inés
A1 - Respaldiza, Miguel A.
A1 - Gomez Tubio, Blanca
A1 - Makarova, Anna
A1 - Smirnov, Dmitry
A1 - Kumar, Sourabh
A1 - Mata, António
A1 - Silveira, João
T1 - Multi-technique computational assessment of fluoride uptake in enamel using PIGE, NEXAFS, and Raman spectroscopy
N2 - This study explores F incorporation in enamel via PIGE, NEXAFS, and Raman spectroscopy, integrating experimental/simulated spectra. Machine Learning boosts data interpretation, offering key insights into F delivery for clinical application.
KW - Simulations
KW - Enamel
KW - Fuorine
KW - NEXAFS
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-631138
DO - https://doi.org/10.1039/D5TB00213C
SN - 2050-750X
SP - 1
EP - 10
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-63113
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pavlidis, Sotirios
A1 - Teutloff, Christian
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Krause, Konstantin B.
A1 - Emmerling, Franziska
A1 - Bittl, Robert
A1 - Abbenseth, Josh
T1 - A Crystalline Bismuth(II) Radical Anion: Synthesis, Characterization, and Reactivity
N2 - AbstractWe report the synthesis of a planarized tris‐amidobismuthane supported by a rigid, bulky NNN pincer ligand, which enforces a T‐shaped geometry at the bismuth center. The Bi(NNN) complex features a low‐lying LUMO with distinct Bi(6p) orbital character as shown by DFT calculations. Cyclic voltammetry reveals a fully reversible one‐electron reduction at E1/2 = –1.85 V versus Fc0/+ in THF. Chemical reduction with KC8 in the presence of 4,7,13,16,21,24‐hexaoxa‐1,10‐diazabicyclo[8.8.8]hexacosane (222‐crypt) enables the isolation of an unprecedented Bi(II) radical anion in high isolated yields. Multi‐frequency EPR, X‐ray absorption spectroscopy and SQUID magnetometry complemented by theoretical calculations confirm localization of the unpaired electron on the bismuth center. Preliminary reactivity studies display radical reactivity as shown by single‐electron transfer chemistry and radical coupling reactions.
KW - Bi(III)
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-644143
DO - https://doi.org/10.1002/anie.202515545
SN - 1433-7851
VL - 64
IS - 49
SP - 1
EP - 6
PB - Wiley VHC-Verlag
AN - OPUS4-64414
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - INPR
A1 - Morcillo, Dalia
A1 - Oelze, Marcus
A1 - Seena Prem, Pranav
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Emmerling, Franziska
A1 - Recknagel, Sebastian
A1 - Panne, Ulrich
A1 - Abad Andrade, Carlos Enrique
T1 - Lithium isotope fractionation as an early indicator of degradation mechanisms in lithium-ion batteries
N2 - Aging in lithium-ion batteries (LIBs) degrades performance and hinders sustainability, demanding advanced diagnostics for early failure prediction. We investigate lithium isotope fractionation (LIF) as an innovative probe of degradation in lithium cobalt oxide (LCO) coin cells aged over 0−700 cycles. High-precision multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) quantified δ7Li variations across cell stages: non-cycled (0 cycles), newly formed (5 cycles), semi-aged (250 cycles), and fully aged (700 cycles). During early cycling (≤ 45 cycles), chemical processes drive 7Li enrichment at the anode (δ7Li vs LSVEC = +12 ‰) through solid electrolyte interphase (SEI) formation, while the cathode depletes in 7Li (δ7Li vs LSVEC = −0.7 ‰). Beyond 45 cycles, electric field-induced migration predominates, promoting 6Li intercalation into the anode and increasing the δ7Li of the cathode by 8.1 ‰. Mass balance verifies isotope conservation, attributing shifts to redistribution and trapping. Complementary electrochemical impedance spectroscopy (EIS) and X-ray absorption spectroscopy and diffraction confirm SEI expansion, cobalt oxidation, lattice shrinkage, and changes in electrode structure, corroborating LIF trends. Notably, a δ7Li inflection at approximately 270 cycles anticipates end-of-life by 70 cycles, surpassing traditional methods in sensitivity. LIF emerges as a predictive indicator of aging mechanisms, informing optimized designs for durable LIBs.
KW - Lithium isotope fractionation
KW - Lithium-ion batteries
KW - Degradation mechanisms
KW - LiCoO2 cathodes
KW - LCO
KW - Isotopic tracing
KW - Lithium isotopes
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-650945
DO - https://doi.org/10.26434/chemrxiv-2025-16lvq
SP - 1
EP - 19
AN - OPUS4-65094
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Yao, Xingyu
A1 - Antunes, Margarida M.
A1 - Guilherme Buzanich, Ana
A1 - Cabanelas, Pedro
A1 - Valente, Anabela A.
A1 - Pinna, Nicola
A1 - Russo, Patrícia A.
T1 - Formation, Phase Transition, Surface, and Catalytic Properties of Cubic ZrO 2 Nanocrystals
N2 - Pseudocapacitance-type transition metal oxides have been extensively investigated as anodes for lithium-ion batteries (LIBs). Currently, they are also gaining attention for sodium-ion batteries (SIBs) due to their low volume change and safety. However, their performance in sodium storage remains limited, primarily due to the larger Na+ ion radius. Here, for the first time, an iron niobate is reported with a columbite structure as a high-Performance sodium storage anode. The presence of iron triggers the loss of long-rangeorder through disorder of the FeO6 octahedra local structure, subsequentlyallowing reversible sodium storage in an amorphous phase. Simultaneously, the formation of short-range ordered zigzag-chain structures within the NbO6 planes creates a “skeleton” that offers abundant active sites forpseudocapacitive ion storage and enhanced ion diffusion pathways. These characteristics of FeNb2O6 make it an effective intercalation host, offering high capacity along with fast Na+ kinetics, as demonstrated through operando and ex situ characterizations. It leads to an applicable reversible capacity (>300 mAh g−1) with a favorable average voltage of ≈0.6 V and excellent rate capability (180.4 mAh g−1 at a current density of 2 A g−1). This study provides insights into the development of intrinsically active transition metal oxides for Na+-ion intercalation.
KW - XAS
KW - Sodium-ion Batteries
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654955
DO - https://doi.org/10.1021/acs.chemmater.5c01483
SN - 0897-4756
VL - 37
IS - 21
SP - 8568
EP - 8580
PB - American Chemical Society (ACS)
AN - OPUS4-65495
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Liu, Yanchen
A1 - Guilherme Buzanich, Ana
A1 - Alippi, Paola
A1 - Montoro, Luciano A.
A1 - Lee, Kug‐Seung
A1 - Jeon, Taeyeol
A1 - Weißer, Kilian
A1 - Karlsen, Martin A.
A1 - Russo, Patrícia A.
A1 - Pinna, Nicola
T1 - FeNb 2 O 6 as a High‐Performance Anode for Sodium‐Ion Batteries Enabled by Structural Amorphization Coupled with NbO 6 Local Ordering
N2 - Pseudocapacitance-type transition metal oxides have been extensively investigated as anodes for lithium-ion batteries (LIBs). Currently, they are also gaining attention for sodium-ion batteries (SIBs) due to their low volume change and safety. However, their performance in sodium storage remains limited, primarily due to the larger Na+ ion radius. Here, for the first time, an iron niobate is reported with a columbite structure as a high-performance sodium storage anode. The presence of iron triggers the loss of long-range order through disorder of the FeO6 octahedra local structure, subsequently allowing reversible sodium storage in an amorphous phase. Simultaneously, the formation of short-range ordered zigzag-chain structures within the NbO6 planes creates a “skeleton” that offers abundant active sites for pseudocapacitive ion storage and enhanced ion diffusion pathways. These characteristics of FeNb2O6 make it an effective intercalation host, offering high capacity along with fast Na+ kinetics, as demonstrated through operando and ex situ characterizations. It leads to an applicable reversible capacity (>300 mAh g−1) with a favorable average voltage of ≈0.6 V and excellent rate capability (180.4 mAh g−1 at a current density of 2 A g−1). This study provides insights into the development of intrinsically active transition metal oxides for Na+-ion intercalation.
KW - SIB
KW - XAS
KW - Sodium-ion Batteries
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654931
DO - https://doi.org/10.1002/adma.202504100
SN - 0935-9648
VL - 37
IS - 46
SP - 1
EP - 13
PB - Wiley
AN - OPUS4-65493
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bustos, Jenna
A1 - Shohel, Mohammad
A1 - Guilherme Buzanich, Ana
A1 - Zakharov, Lev
A1 - Buils, Jordi
A1 - Segado‐Centellas, Mireia
A1 - Bo, Carles
A1 - Nyman, May
T1 - Technetium and Rhenium Auto‐reduction, Polymerization and Lability towards Group VII Polyoxometalate Chemistry
N2 - AbstractGroup VII Tc and Re have long been studied to develop both radiopharmaceuticals and technologies for nuclear materials management. Fundamental research has targeted understanding this periodic table crossroads where polyoxometalates meets metal‐metal bonded complexes. Here we have isolated green hygroscopic and metastable crystals of (ReVI,oct)2(ReVII,tet)2(OH)2(O)12⋅H2O (ReVI,VII‐green, tet=tetrahedral, oct=octahedral), determined by single‐crystal x‐ray diffraction. In addition to color, Re‐L1 X‐ray absorption near‐edge spectroscopy confirms the reduced oxidation state. ReVI,VII‐green provides the first demonstration of Re autoreduction, long‐observed for Mn and Tc. We also isolated and structurally characterized [Tc4O4(H2O)2(ReO4)14]2− (Tc4Re14) polyanion crystals that contain Tc(V) and Re(VII), consistent with greater stability of reduced Tc compared to reduced Re. Small angle X‐ray scattering of both compounds and prior‐reported polyanion [Tc4O4(H2O)2(TcO4)14]4− (Tc20) dissolved in acetonitrile indicated a qualitative lability order of oxo‐linkages of Re‐O−Re Re‐O−Tc Tc‐O−Tc, and lability of Tc20 was also probed by 99Tc nuclear magnetic resonance spectroscopy. Computation provided insight into 99Tc chemical shifts as well as lability. Based on both reducibility and solution phase dynamics of polynuclear compounds investigated here, Re is an imperfect surrogate for Tc, and further expansion of group VII polyoxometalate chemistry seems promising.
KW - XANES
KW - Polyoxometalate
KW - Technetium
PY - 2025
DO - https://doi.org/10.1002/chem.202404144
SN - 0947-6539
VL - 31
IS - 21
SP - 1
EP - 7
PB - Wiley-VCH Verl.
AN - OPUS4-65491
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Habibimarkani, Heydar
A1 - Abram, Sarah-Luise
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Prinz, Carsten
A1 - Sahre, Mario
A1 - Hodoroaba, Vasile-Dan
A1 - Radnik, Jörg
T1 - In-depth analysis of FeNi-based nanoparticles for the oxygen evolution reaction
N2 - This study investigates the effect of varying iron-to-nickel ratios on the catalytic performance of Fe-Ni oxide nanoparticles (NPs) for the oxygen evolution reaction (OER). Addressing the issue of high energy wastage due to large overpotentials in OER, we synthesized and characterized different NP catalysts with different Fe: Ni oxide ratios. Transmission Electron Microscopy (TEM), Energy Dispersive X-ray Spectroscopy (EDS), and X-ray Diffraction (XRD) were employed to determine the morphology, elemental and phase composition of the NPs. Furthermore, in-depth profiling with X-ray Photoelectron Spectroscopy (XPS) and Hard X-ray Photoelectron Spectroscopy (HAXPES) revealed that iron predominantly exists as oxide, while nickel exhibits both metallic and oxidic forms depending on the Fe content. XPS indicated an enrichment of iron at the NP surface, whereas HAXPES and EDS data agreed on the bulk stoichiometry. The assessment of the catalytic activity via cyclic voltammetry (CV) showed that the Fe: Ni ratio of 2:3 exhibited superior performance, characterized by lower overpotential and a smaller Tafel slope.
KW - Fe-Ni oxide
KW - Nanoparticles
KW - OER
KW - Catalytic performance
KW - Cyclic voltammetry
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-626932
UR - https://www.nature.com/articles/s41598-025-92720-3
DO - https://doi.org/10.1038/s41598-025-92720-3
VL - 15
IS - 1
SP - 1
EP - 17
PB - Springer Nature
AN - OPUS4-62693
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Thiodjio Sendja, Bridinette
A1 - Tchouank Tekou, Carol Trudel
A1 - Prinz, Carsten
A1 - de Oliveira Guilherme Buzanich, Ana
T1 - Adsorptive performance of single-walled carbon nanotubes for divalent manganese sorption characterized by X-ray absorption spectroscopy
N2 - The adsorptive performance of divalent manganese onto single-walled carbon nanotubes (SWCNTs) is investigated by X-ray absorption spectroscopy (XAS). The study is focused on the one hand, on the use of SWCNT as adsorbent to remove divalent manganese II) pollutant controlling batch parameters such as pH, adsorbent dose and contact time; and on the other hand, on the characterization of manganese adsorbed by SWCNT (Mn-SWCNT) adsorbent to probe the chemical composition, oxidation state, and local structural environment of Mn absorber. Freundlich adsorption isotherm well fitted the experimental data and suggested the maximum adsorption capacity at pH 2. Ion exchange was proposed as the main adsorption mechanism for removing manganese using SWCNT. XAS results revealed the change in the oxidation state of manganese. The effect of pH, adsorbent dose, and contact time is shown. XAS also showed that Mn-SWCNT material is principally composed of MnCl2, Mn2O3, MnO2, Mn3O4, and MnO in decreasing order with MnCl2 and Mn2O3 as major compounds.
KW - Local environment
KW - Single-walled carbon nanotubes
KW - Divalent manganese
KW - Adsorptive performance
KW - X-ray absorption spectroscopy
KW - Oxidation state
PY - 2025
DO - https://doi.org/10.1007/s11696-025-04418-5
SN - 0366-6352
SP - 1
EP - 15
PB - Springer Science and Business Media LLC
AN - OPUS4-64492
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Gong, Mengjun
A1 - Mehmood, Asad
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Fellinger, Tim-Patrick
A1 - Jackson, Colleen
A1 - Cui, Junyi
A1 - Drazic, Goran
A1 - Kucernak, Anthony
T1 - Designing Co–N/C Cathode Catalysts with Dense Atomic Cobalt Sites for Enhanced PEMFC Performance
N2 - Metal-nitrogen/carbon (M-N/C) catalysts, particularly those incorporating Fe,Co, or Mn, are among the most promising non-platinum group catalysts forthe acidic oxygen reduction reaction (ORR) in fuel cells. This study reports aCo-N/C catalyst featuring high (3 wt%) cobalt content exclusively present asatomic sites. Extended X-ray absorption fine structure analysis confirms atetrapyridinic Co-N4 coordination environment in the optimized (3.0)Co-N/C𝚫catalyst. The high cobalt loading leads to a significant density ofelectrochemically accessible active sites, 3.58 × 10 19 sites g−1 , quantified viathe nitrite stripping method. The catalyst demonstrates excellent ORR activityin a rotating ring-disk electrode setup, achieving a half-wave potential (E 1/2 ) of0.76 V at a low loading of 0.2 mg cm−2 and a mass activity of 3.5 A g−1 at 0.80VRHE . Single-cell hydrogen-oxygen PEMFC tests achieve a peak power densityexceeding 1.3 W cm−2 (iR-corrected). Under hydrogen-air condition, thecatalyst delivers 0.54 A cm−2 at 0.60 V (0.39 W cm−2 ). Despite the intrinsicallyhigher turnover frequency of Fe-based sites, the optimized(3.0)Co-N/C𝚫 catalyst achieves similar fuel cell performance to that of Fe-N/C,highlighting the critical role of site density in overall activity.
KW - Fuel cells
KW - Single atom catalysts
KW - Oxygen reduction reaction
KW - Non-precious catalysts
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-644276
DO - https://doi.org/10.1002/advs.202516060
SN - 2198-3844
SP - 1
EP - 11
PB - Wiley VHC-Verlag
AN - OPUS4-64427
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Heinekamp, Christian
A1 - Roy, Arkendu
A1 - Karafiludis, Stephanos
A1 - Kumar, Sourabh
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Stawski, Tomasz M.
A1 - Miliūtė, Aistė
A1 - von der Au, Marcus
A1 - Ahrens, Mike
A1 - Braun, Thomas
A1 - Emmerling, Franziska
T1 - Zirconium fluoride-supported high-entropy fluoride: a catalyst for enhanced oxygen evolution reaction
N2 - Extended hydrogen initiatives promote the urgency of research on water splitting technologies and, therein, oxygen evolution reaction catalysts being developed. A route to access a ZrF4 supported high-entropy fluoride catalyst using a facile sol–gel route is presented. The high-entropy character of the catalyst was confirmed by scanning transmission electron microscopy and energy dispersive X-ray spectroscopy (STEM-EDX) as well as inductively coupled plasma-mass spectrometry (ICP-MS). Additional investigations on the local structure were performed using extended X-ray absorption fine structure spectroscopy (EXAFS) and pair distribution function (PDF) analysis. The catalyst shows significant potential for oxygen evolution reaction (OER) in alkaline media with a current density of 100 mA cm−2 at approximately 1.60 V, thus outperforming benchmark materials such as IrO2, despite a significant reduction in electrochemical mass loading. A potential mechanism is suggested based on free energy calculation using DFT calculations.
KW - OER
KW - HEA
KW - CCMAT
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-637116
DO - https://doi.org/10.1039/D4TA08664C
SN - 2050-7488
VL - 13
IS - 26
SP - 20383
EP - 20393
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-63711
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - de Oliveira Guilherme Buzanich, Ana
T1 - The versatility of X-ray absorption spectroscopy (XAS) for exploring new materials in collaborative research
N2 - With increasing demand and environmental concerns, researchers are exploring new materials that can perform as well or better than traditional materials while reducing environmental impact. X-ray absorption spectroscopy (XAS) enables unique atom-specific tool to probe the electronic structure of materials. The BAM plays a central role in this highly collaborative research. The BAMline, a real-life sample materials research beamline, at the Berlin Synchrotron BESSY-II, provides unique insights into materials’ electronic and chemical structure at different time and length scales. This enables real-time optimization of material properties and performance for various applications, such as energy storage and conversion, catalysis, and corrosion resistance. This talk provides an overview of the analytical methods and sample environments of the BAMline and addresses its potential for further advances in sustainable materials research.
T2 - International symposium of radiation physics (ISRP-16)
CY - Lisbon, Portugal
DA - 01.09.2024
KW - XAS
KW - Time-resolved studies
KW - Operando
KW - Corrosion
KW - Electrochemistry
PY - 2024
AN - OPUS4-60996
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -