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This study develops an integrated X‐ray absorption spectroscopy (XAS) photoemission electron microscopy (PEEM) platform on beamline BL09U at the Shanghai Synchrotron Radiation Facility (SSRF), enabling nanoscale characterization of complex materials through energy‐resolved imaging and local‐area XAS. By using the wide range of energy tunability, full access to different polarizations and PEEM's surface sensitivity, we have established a gap–monochromator control system under the EPICS framework to synchronize the elliptically polarized undulator (EPU) gap and monochromator energy dynamically, optimizing photon flux stability for absorption fine structure analysis. Combining X‐ray magnetic circular dichroism (XMCD) and X‐ray magnetic linear dichroism (XMLD) with PEEM and local‐area XAS, this platform achieves concurrent mapping of electronic structures and magnetic domains in ferromagnetic nano‐patterns, as demonstrated through our studies of Ni80Fe20 Permalloy using this system. The dual‐modal approach bridges synchrotron radiation technology and surface science, offering nanometre‐scale spatial resolution in XAS with magnetic domain sensitivity through linearly and circularly polarized X‐ray excitation, providing researchers with advanced tools for functional materials analysis through synergistic XAS‐PEEM techniques and dynamic control systems. This study develops the energy‐resolved photoemission electron microscopy imaging and micro‐zone X‐ray absorption spectroscopy (XAS) method. By integrating X‐ray magnetic circular dichroism, X‐ray magnetic linear dichroism and micro‐zone XAS, we have achieved spatially resolved electronic structure mapping and magnetic property analysis at the nanoscale level. We have also developed a gap–monochromator linkage control system to optimize photon flux and its stability.

Mn4N, a ferrimagnet that does not contain rare-earth elements, possesses attractive properties for spintronics applications. In particular, Mn4N epitaxial films exhibit a small spontaneous magnetization of about 100 kA m− 1, a large spin polarization (p = 0.8), and large perpendicular magnetic anisotropy with a magnetic anisotropy constant of approximately 105 J m− 3. More importantly, achieving magnetic compensation at room temperature is possible through impurity doping. This property is particularly significant for spin-torque-based spintronics applications. In the vicinity of the magnetization and/or angular momentum compensation points, magnetization dynamics can be substantially accelerated, enabling high-speed switching and domain wall motion. This article surveys the magnetic properties of impurity-doped Mn4N epitaxial films grown on SrTiO3(001) substrates, highlighting recent results obtained with Cu-, Ag-, Au-, and Pd-doped Mn4N films in comparison with Ni- and Cr-doped Mn4N films. Furthermore, with a view to device applications of Mn4N, we present the formation of ultrathin ( 4 nm) Pt epitaxial films with a < 100 > orientation on MgO(001), which is essential for injecting spins into Mn4N-based overlayers by utilizing the spin Hall effect of heavy metals.

The results of the 2018 commissioning and experimental campaigns of the new High Power Laser Facility on the Energy-dispersive X-ray Absorption Spectroscopy (ED-XAS) beamline ID24 at the ESRF are presented. Results of the 2018 commissioning and experimental campaigns of the new High Power Laser Facility on the Energy-dispersive X-ray Absorption Spectroscopy (ED-XAS) beamline ID24 at the ESRF are presented. The front-end of the future laser, delivering 15 J in 10 ns, was interfaced to the beamline. Laser-driven dynamic com­pression experiments were performed on iron oxides, iron alloys and bismuth probed by online time-resolved XAS.

Exploring efficient and cost-effective catalysts to replace precious metal catalysts, such as Pt, for electrocatalytic oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) holds great promise for renewable energy technologies. Herein, we prepare a type of Co catalyst with single-atomic Co sites embedded in hierarchically ordered porous N-doped carbon (Co-SAS/HOPNC) through a facile dual-template cooperative pyrolysis approach. The desirable combination of highly dispersed isolated atomic Co-N₄ active sites, large surface area, high porosity, and good conductivity gives rise to an excellent catalytic performance. The catalyst exhibits outstanding performance for ORR in alkaline medium with a half-wave potential (E 1/2) of 0.892 V, which is 53 mV more positive than that of Pt/C, as well as a high tolerance of methanol and great stability. The catalyst also shows a remarkable catalytic performance for HER with distinctly high turnover frequencies of 0.41 and 3.8 s−1 at an overpotential of 100 and 200 mV, respectively, together with a long-term durability in acidic condition. Experiments and density functional theory (DFT) calculations reveal that the atomically isolated single Co sites and the structural advantages of the unique 3D hierarchical porous architecture synergistically contribute to the high catalytic activity.

X‐ray absorption spectroscopy (XAS) is a critical analytical technique for comprehensively characterizing the electronic configurations and atomic structures of materials. The rapid growth in both data volume and complexity, driven by modern synchrotron radiation facilities, necessitates computational frameworks capable of efficiently processing large‐scale XAS datasets. To address this need, we introduce XASDAML, a machine‐learning‐based platform that integrates the entire data processing workflow. The framework coordinates key operational processes, including spectral–structural descriptor generation, predictive modeling and performance validation, while facilitating statistical analyses through principal component decomposition and clustering algorithms to uncover latent patterns within datasets. Designed with modular architecture, the system enables independent modification or enhancement of individual components, ensuring flexibility to meet evolving analytical demands. Implemented through a Jupyter Notebook‐based interface, the platform ensures accessibility for researchers. The framework is validated with two case studies: (i) copper‐foil EXAFS data show that it can predict coordination numbers and radial distribution functions; and (ii) XANES spectra of the spin‐crossover complex Fe(phen)3 uncover bond‐length changes between the low‐spin and high‐spin states. Comprehensive validation highlights robust toolkit functionalities, including statistical descriptor analyses, spectral visualization, and prediction of widely employed structural descriptors closely reflecting local atomic environments. By establishing standardized and extensible procedures for integrating machine learning into XAS analysis, XASDAML enhances research efficiency, promotes richer data insights, and provides a versatile computational resource tailored to the expanding needs of XAS research. We introduce XASDAML, an open‐source machine‐learning framework that integrates the complete X‐ray absorption spectroscopy analytical workflow, enabling efficient extraction of spectral and structural descriptors and rapid prediction of structural parameters. Demonstrated through a copper system, the framework significantly streamlines X‐ray absorption spectroscopy data analysis and enhances model accuracy and interpretability, facilitating deeper insight into materials characterization.

A novel approach to soft X-ray fluorescence-yield absorption spectroscopy is presented using a superconducting tunnel junction (STJ) X-ray detector, a new type of detector for the soft X-ray region. The STJ detector offers superior energy resolution compared with silicon drift detectors and higher detection efficiency than grating-based spectrometers, both of which are widely used in soft X-ray spectroscopy. The STJ detector can simultaneously detect multiple fluorescence lines in a single measurement, even on a bending-magnet beamline, which enables medium -energy-resolution fluorescence detected X-ray absorption spectroscopy (XAS) without the need for large-scale emission spectrometers. Using these characteristics, the Ti L α/ L ℓ XAS and O K α XAS of SrTiO 3 were measured, where Ti L ℓ XAS are expected to reflect the intrinsic Ti 3 d electronic states without being affected by orbital anisotropy, providing a more accurate picture of the transition-metal electronic structure. These results demonstrate that the STJ detector is effective for probing anion electronic states of carbides, nitrides and oxides.

Results of the 2018 commissioning and experimental campaigns of the new High Power Laser Facility on the Energy‐dispersive X‐ray Absorption Spectroscopy (ED‐XAS) beamline ID24 at the ESRF are presented. The front‐end of the future laser, delivering 15 J in 10 ns, was interfaced to the beamline. Laser‐driven dynamic compression experiments were performed on iron oxides, iron alloys and bismuth probed by online time‐resolved XAS. The results of the 2018 commissioning and experimental campaigns of the new High Power Laser Facility on the Energy‐dispersive X‐ray Absorption Spectroscopy (ED‐XAS) beamline ID24 at the ESRF are presented.

Breakthroughs in energy storage and conversion devices depend heavily on the exploration of low-cost and high-performance materials. Carbon-supported electrocatalysts with dimensional varieties have recently attracted significant attention due to their strong structural flexibility and easy accessibility. Nevertheless, understanding the connection between their electronic, structural properties, and catalytic performance must remain a top priority. Synchrotron radiation (SR) X-ray absorption spectroscopy (XAS) techniques, including hard XAS and soft XAS, are recognized as efficient and comprehensive platforms for probing the surface, interface, and bulk electronic structure of elements of interest in the materials community. In the past decade, the flourishing development of materials science and advanced characterization technologies have led to a deeper understanding at different temporal, longitudinal, and spatial scales. In this review, we briefly describe the concept of XAS techniques and summarize their recent progress in addressing scientific questions on carbon-supported electrocatalysts through the development of advanced instruments and experimental methods. We then discuss the remaining challenges and potential research directions in next-generation materials frontiers, and suggest challenges and perspectives for shedding light on the structure–activity relationship.

Polymer dielectric‐based organic field‐effect transistors (OFETs) have attracted significant attention due to their potential applications in transparent and flexible electronics, intelligent labels for smart packaging, and chemical and biosensors. Herein, we demonstrate OFETs incorporating poly(chloro‐p‐xylylene) (parylene‐C) as the gate dielectric with variable thickness in the range of 250–450 nm in 50 nm increments, with careful investigation of their electrical characteristics. The results showed that an optimal dielectric thickness of parylene‐C (350 nm) significantly enhanced device performance compared to a standard SiO2 dielectric, achieving a low threshold voltage (VTh) (0.23 V), a higher on/off ratio (Ion/off) (7.27 × 103), and increased hole mobility (µh) (1.29 × 10−2 cm2V−1s−1). To understand how the thickness of the parylene‐C dielectric layer influences the performance of OFETs, a variety of analyses were conducted, including capacitance‐voltage and water contact angle measurements, atomic force microscopy, and grazing incidence wide‐angle X‐ray scattering. Furthermore, X‐ray absorption spectroscopy was employed to analyze the electronic structure and molecular orientation of parylene‐C and the PBTTT‐C14 layer deposited on it. This study offers valuable insights for optimizing OFETs with parylene‐C dielectric layers, paving the way for the development of next‐generation flexible and low‐power electronic devices. This study examines the π–π stacking behavior of organic semiconductors on poly(chloro‐p‐xylylene) dielectric layers and elucidates its influence on molecular ordering and charge transport properties. Based on these observations, organic transistors with optimized electrical performance are fabricated, offering valuable insights for the development of next‐generation optoelectronic devices with enhanced stability and efficiency.

In photocatalysis, a set of elemental steps are involved together at different timescales to govern the overall efficiency of the process. These steps are divided as follow: (1) photon absorption and excitation (in femtoseconds), (2) charge separation (femto- to picoseconds), (3) charge carrier diffusion/transport (nano- to microseconds), and (4 and 5) reactant activation/conversion and mass transfer (micro- to milliseconds). The identification and quantification of these steps, using the appropriate tool/technique, can provide the guidelines to emphasize the most influential key parameter that improve the overall efficiency and to develop the “photocatalyst by design” concept. In this review, the identification/quantification of reactant activation/conversion and mass transfer (steps 4 and 5) is discussed in details using the in situ/operando techniques, especially the infrared (IR), Raman, and X-ray absorption spectroscopy (XAS). The use of these techniques in photocatalysis was highlighted by the most recent and conclusive case studies which allow a better characterization of the active site and reveal the reaction pathways in order to establish a structure–performance relationship. In each case study, the reaction conditions and the reactor design for photocatalysis (pressure, temperature, concentration, etc.) were thoroughly discussed. In the last part, some examples in the use of time-resolved techniques (time-resolved FTIR, photoluminescence, and transient absorption) are also presented as an author’s guideline to study the elemental steps in photocatalysis at shorter timescale (ps, ns, and µs).