With the development of the semiconductor industry below the 7 nm scale, critical dimension small-angle X-ray scattering (CD-SAXS) has emerged as a powerful tool for quantitatively measuring nanoscale deviations. In this study, the effects of X-ray beam size and photon energy on the accuracy of critical dimension measurements were investigated. Critical dimensions measured using beams with different spot sizes showed different deviations from the expected values. Beam sizes that were either too large or too small did not improve confidence intervals. As the incident energy increased, the X-ray transmission rate increased, while the scattering cross section decreased, resulting in a gradual decrease in the signal-to-noise ratio of the diffraction peaks, which reduced the accuracy of the CD-SAXS measurements. An optimal accuracy was obtained at 12 keV with a smaller beam size. Using an effective trapezoid model, the results yielded an average pitch of 100.4 ± 0.2 nm, width of 49.8 ± 0.2 nm, height of 130.0 ± 0.2 nm, and a sidewall angle below 1.1^∘± 0.1^∘ . These results provide crucial guidance for the future development of CD-SAXS laboratories and the construction of X-ray machines as well as robust support for research in related fields.

The Radioactive Materials Beamline (BL13SSW) of the Shanghai Synchrotron Radiation Facility (SSRF) Phase-II project is a new beamline aimed at meeting research demands in fields involving radioactive materials, such as fundamental radiochemistry and nuclear waste disposal. Advanced experimental methods have been developed based on a wiggler source with a wide tunable energy range of 5–50 keV, including high-resolution X-ray diffraction (HR-XRD), high-resolution X-ray spectroscopy (HR-XES), and high-resolution X-ray absorption spectroscopy (HR-XAS). It can also provide routine XRD, two-dimensional XRD, pair distribution function (PDF), X-ray absorption spectroscopy (XAS), X-ray fluorescence (XRF), and microbeam characterization. A radioactive sample experimental environment, including sample radiation detection and monitoring, a storage room, and a ventilation system, was built along with the beamline. This is the first comprehensive synchrotron radiation beamline in China dedicated to research on radioactive materials.

With the continuous scaling of advanced semiconductor manufacturing processes, device critical dimensions (CD) are shrinking rapidly and transistor structures are evolving from planar to complex 3D architectures. These trends make critical dimension small-angle X-ray scattering (CD‑SAXS) an indispensable metrology technique for nanostructures. However, conventional CD‑SAXS workflows suffer from two major efficiency bottlenecks: time‑consuming multi‑angle data acquisition and low‑efficiency inverse modeling based on nonlinear fitting. This study aims to overcome these limitations and realize high‑efficiency CD‑SAXS measurement. A dual‑path acceleration strategy is proposed, which integrates a ResNet34‑based deep regression network with Test‑Time Training (TTT). The neural network is pre‑trained on physically simulated scattering data and then fine‑tuned with unlabeled experimental data to reduce the simulation‑to‑reality domain shift and improve generalization. Raw scattering data is converted into a ω‑qxz coordinate format suitable for convolutional neural networks, thereby avoiding the reconstruction of qx‑qz reciprocal space patterns. The TTT mechanism ensures high prediction accuracy under sparse angular sampling. Experimental results demonstrate that the proposed method achieves measurement accuracy comparable to traditional nonlinear fitting methods, while reducing the total time of measurement and data processing by more than 30‑fold. The dual‑path acceleration strategy effectively breaks through the efficiency bottlenecks of conventional CD‑SAXS. It enables accurate nanostructure measurement with greatly reduced data acquisition and processing time, showing strong potential for CD‑SAXS in real‑time, in‑line metrology of complex nanostructures in semiconductor manufacturing.

For beamlines with numerous experimental methods and a need for high automation, system integration and operational management face significant challenges. As the only synchrotron radiation X-ray beamline in China capable of conducting experiments with radioactive samples, the Radioactive Materials Beamline (BL13SSW) of Shanghai Synchrotron Radiation Facility (SSRF) features multiple experimental methods. Meanwhile, it has over 100 online control objects, it is necessary to coordinate the functions of various components in real time to support the execution and switching of different experimental methods. To address this, a distributed integrated control and data acquisition system suitable for the BL13SSW beamline has been designed and developed based on EPICS, CSS and Python. It is designed based on the concept of loose coupling and modular design, and it decomposes various experimental tasks into independent subtasks. The system adopts a TTL synchronous pulse trigger mechanism to achieve precise synchronization among multiple acquisition systems, which effectively reduces data acquisition latency and improves the signal-to-noise ratio of experimental data. To address acquisition interruptions or pauses caused by communication delays or controller and detector electronics errors, a 2-s judgment logic is integrated to ensure the program can resume automatically. For radioactive sample measurements with low concentration and high signal-to-noise ratio requirements, the system is equipped with state-of-the-art low-noise data acquisition electronics. In addition, to handle the large number of devices and high network load at the beamline, network isolation is implemented for high-bandwidth online equipment, ensuring stable and smooth system operation without lag. Finally, experimental verification of the software's functions and performance are carried out on various samples under different experimental methods. The experimental results show that the software operates stably, realizing the unified integration and automated control of multiple experimental methods, and significantly improving the experimental efficiency of the beamline and the convenience of user operations. Currently, this system has been officially opened for user operation.

Optimizing the morphology of the active layer is crucial for achieving high photovoltaic conversion efficiency in all-polymer solar cells (APSCs). Solvent vapor annealing (SVA) is an essential post-treatment strategy for controlling active layer morphology. However, most current SVA are conducted ex situ, limiting their ability to accurately reveal the morphological evolution of active layers of APSCs. In this study, in situ synchrotron radiation GIWAXS and in situ UV-vis spectroscopy combined with GISAXS is used to monitor the morphological evolution of PM6/PY-IT blends during the SVA process in real-time. Results showed that the PY-IT absorption peak exhibited a red shift under a nonpolar carbon disulfide vapor, while a blue shift is observed during the SVA process with a polar chloroform vapor. The SVA process can be divided into three stages: solvent swelling, recrystallization, and molecular rearrangement. For thermally pre-annealed samples subjected to chloroform SVA, the power conversion efficiency (PCE) increased by 15.1%. The improved PCE stems from reduced crystal plane spacing (d-spacing), enhanced crystal coherence length, and optimal phase separation via SVA. Pre-annealing suppresses excessive swelling, emphasizing the reordering dynamical role in the morphology of APSCs. This study offers insights into balancing SVA conditions to maximize performance and minimize adverse effects.

The construction of a new beamline,BL10U1,was completed at the Shanghai synchrotron radiation facility in 2020.This multipurpose beamline was designed to provide X-ray scattering techniques such as ultra-small-angle X-ray scattering(USAXS),small-angle X-ray scattering(SAXS),wide-angle X-ray scattering,and microfocus SAXS(μSAXS)for a broad user community.To realize fast time-resolved USAXS experiments,the beamline adopted an in-vacuum undulator with a total length of 1.6 m as the photon source.An in-house cryogenic-cooled double multilayer monochromator was installed to deliver a photon flux of approximately 1013 photons/s at a photon energy of 10 keV.The three-year successful operation of this beamline demonstrated that the monochromator operated smoothly,as expected.BL10U1 has three end stations in succession:USAXS end station,μSAXS end station,and end station for industrial applications.The minimum scattering vector q～0.0042 nm-1 at 10 keV can be achieved at the USAXS end station equipped with a 28 m-long and 1.8 m-diameter vacuum flight tube.At the μSAXS end station,a beam spot of less than 10 × 8 μm was achieved for micro-SAXS experiments.In contrast,in situ experimental instruments up to 5 m high and 8 m wide can be mounted at the industrial application end station,which offers industrial scientists the opportunity to use their large industrial equipment.BL10U1 opens up a new capability to investigate phenomena such as non-equilibrium and dynamic processes of materials with a wide length scale from angstroms to micrometers with millisecond time resolution.In this paper,we also report beamline design considera-tions and commissioning results.

Abstract Catalyst systems populated by high-density single atoms are crucial for improving catalytic activity and selectivity, which can potentially maximize the industrial prospects of heterogeneous single-atom catalysts (SACs). However, achieving high-loading SACs with metal contents above 10 wt% remains challenging. Here we describe a general negative pressure annealing strategy to fabricate ultrahigh-loading SACs with metal contents up to 27.3–44.8 wt% for 13 different metals on a typical carbon nitride matrix. Furthermore, our approach enables the synthesis of high-entropy single-atom catalysts (HESACs) that exhibit the coexistence of multiple metal single atoms with high metal contents. In-situ aberration-corrected HAADF-STEM (AC-STEM) combined with ex-situ X-ray absorption fine structure (XAFS) demonstrate that the negative pressure annealing treatment accelerates the removal of anionic ligand in metal precursors and boosts the bonding of metal species with N defective sites, enabling the formation of dense N-coordinated metal sites. Increasing metal loading on a platinum (Pt) SAC to 41.8 wt% significantly enhances the activity of propane oxidation towards liquid products, including acetone, methanol, and acetic acid et al. This work presents a straightforward and universal approach for achieving many low-cost and high-density SACs for efficient catalytic transformations.

By substituting the oxygen evolution reaction (OER) with the anodic urea oxidation reaction (UOR), it not only reduces energy consumption for green hydrogen generation but also allows purification of urea-rich wastewater. Spin engineering of the d orbital and oxygen-containing adsorbates has been recognized as an effective pathway for enhancing the performance of electrocatalysts. In this work, we report the fabrication of a bifunctional electrocatalyst composed of amorphous RuO2-coated NiO ultrathin nanosheets (a-RuO2/NiO) with abundant amorphous/crystalline interfaces for hydrogen evolution reaction (HER) and UOR. Impressively, only 1.372 V of voltage is required to attain a current density of 10 mA cm-2 over a urea electrolyzer. The increased oxygen vacancies in a-RuO2/NiO by incorporation of amorphous RuO2 enhance the total magnetization and entail numerous spin-polarized electrons during the reaction, which speeds up the UOR reaction kinetics. The density functional theory study reveals that the amorphous/crystalline interfaces promote charge-carrier transfer, and the tailored d-band center endows the optimized adsorption of oxygen-generated intermediates. This kind of oxygen vacancy induced spin-polarized electrons toward boosting HER and UOR kinetics and provides a reliable reference for exploration of advanced electrocatalysts.

The growth of lithium dendrites and the shuttle of polysulfides in lithium metal batteries (LMBs) have hindered their development. In LMBs, the cathode and anode are separated by a separator, although this does not solve the battery's issues. The use of biomass materials is widespread for modifying the separator due to their porous structure and abundant functional groups. LMBs perform more electrochemically when lithium ions are deposited uniformly and polysulfide shuttling is reduced using biomass separators. In this review, we analyze the growth of lithium dendrite and the shuttle of polysulfide in LMBs, summarize the types of biomass separator materials and the mechanisms of action (providing mechanical barriers, promoting uniform deposition of metal ions, capturing polysulfides, shielding polysulfide). The prospect of developing new separator materials from the perspective of regulating ion transport and physical sieving efficiency as well as the application of advanced technologies such as synchrotron radiation to characterize the mechanism of action of biomass separators is also proposed.

The introduction of solvent additives is one of the most common approaches for enhancing the power conversion efficiency of organic solar cells (OSCs). However, the use of solvent additives has some negative effects, and an understanding of how solvent additives affect OSCs is currently limited. In this study, we developed an in situ grazing incidence wide-angle X-ray scattering (GIWAXS) technique in the SAXS beamline (BL16B1) at the Shanghai Synchrotron Radiation Facility, and the additive effects of 1,8-diiodoctane (DIO) on the performance and morphology evolution of the PTB7-Th/PC71BM device was investigated in depth. The results revealed that the crystal size increased with the volume ratio of DIO, and a drastic evolution of lattice space and crystal coherence length was observed during thermal annealing for the first time, to our knowledge. The discrete PC71BM molecules dissolved by DIO have an effect similar to that of the nucleating agent for PTB7-Th, boosting the crystallization of PTB7-Th, reducing phase separation, and inducing more drastic morphological evolution during thermal annealing. Our results provide a deep perspective for the mechanism of solvent additives, while also showing the significance and feasibility of the in situ GIWAXS technique we developed at BL16B1.

An online monitoring device is designed for the real-time monitoring of hard X-ray beams at Shanghai Synchrotron Radiation Facility (SSRF). Compared with the existing beam position monitors and gas ionization chambers, it can monitor the beam position, size, and flux, and reconstruct the relative phase variation of the incident wavefront with an acquisition speed of 2 kHz, without affecting the downstream experiments. In addition, it has potential applicability for feedbacks of the optical devices and experimental positions in super-long and micronano-focused beamline stations. Experiments are carried out in the USAXS and micro-focusing SAXS experimental stations at SSRF, and beam stability data are collected at common experimental frame rates. The time-frequency domain signals of position, flux, and size distribution of the incident beam are analyzed, and the phase variation of the incident wavefront is obtained as well. Finally, the feasibility of this device is verified.

Electrocatalytic performance of low-cost graphitic carbon nitride (CN) is greatly limited by its limited conductivity and small specific surface area. Herein, a simple and cost-effective idea to produce novel nanocomposite is constructed by the CN and cetyl trimethyl ammonium bromide functionalized carbon black (CB) anchored platinum nanoparticles as highly efficient oxygen reduction catalysts based on gamma irradiation. The assembled carbon nitride/positive carbon black anchoring PtNPs (Pt/CN 2 -CB + 1 ) catalyst exhibits significantly improved specific surface area, high graphitization, and uniformly dispersed ultra-small platinum nanoparticles. For the oxygen reduction reaction (ORR) performance, the catalyst shows more positive onset-potential (0.93 V versus RHE) and larger diffusion limiting current density (5.65 mA cm −2 ) compared with benchmark Pt/C catalysts in alkaline medium. Moreover, the Pt/CN 2 -CB + 1 catalyst exhibits a small Tafel slope (92 mV dec −1 ). Besides, the catalyst was demonstrated the remarkable methanol tolerance and good long-term stability under working conditions. This work provides a new and effective γ -rays irradiation for synthesizing the carbon nitride catalysts for energy conversion and storage applications.

Molybdenum disulfide (MoS2) has possession of a layered structure and high theoretical capacity, which is a candidate anode material for sodium ion batteries. However, unmodified MoS2 are inflicted with a poor cycling stability and an inferior rate capability upon charge/discharge processes. Considering that the shape and size of anode materials play a key role in the performance of anode materials, this paper proposes a multi-level composite structure formed by the micro-nano materials based on self-assembled molybdenum disulfide (MoS2) nanoflowers, Mxene and hollow carbonized kapok fiber (CKF). The micro-nano materials can be connected to form heterojunction and agglomeration can be avoided. The load bearing of heterostructure and stress release of CKF are coordinated to form a double protection mechanism, which improves the conductivity and structural stability of hybrid materials. Based on the above advantages, it has higher specific capacity than pure MoS2, and has better rate performance (639.3, 409.5, 386.2, 372, 338, 422.8 and 434.7 mAh g-1 at the current density of 0.05, 0.1, 0.2, 0.5, 1 ,0.1 and 0.05 A·g-1, respectively). The stress-modulated strategies can provide new insights for the design and construction of transition metal sulfides heterostructures to achieve high performance sodium ion batteries.

Graphynes have great application potential in energy storage and conversion. However, due to the limitation of specific surface area and active site, their energy storage capacity and catalytic efficiency are expected to be further improved. Defect engineering is a complex technique that can alter the geometry and chemical envi-ronment of a subject via introducing defects. Defects such as vacancy and heteroatom can expose a lot of co-ordination unsaturated sites, change the charge distribution around the carbon atom and improve graphynes cycle stability, thus markedly promoting the catalytic activity and significantly optimizing the battery energy storage of graphynes. In this paper, the research progress of defect engineering of graphynes in energy storage, electrocatalysis and photocatalysis is reviewed. Firstly, the classification of defects in solid materials and the forms of various defects in graphynes are given. Secondly, the application of different defect types, such as elemental doping, vacancy, single-atom catalyst and heterojunction on graphynes for energy storage, catalysis and solar cells are introduced. Finally, the opportunities and challenges for the future research on defective graphynes are discussed.

BackgroundThe quality of the experimental data is closely related to the optimal optical conditions of the end-station in the small-angle X-ray scattering (SAXS) beamline (lower scattering background, accurate beam intensity before and after the sample, etc.). At present, the optical conditions of the end-station are manually optimized in SAXS beamline (BL16B1) of shanghai synchrotron radiation facility (SSRF), which can not utilize the user's time effectively.PurposeThis study aims to design and implement an automatic calibration procedure with Python on the platform of EPICS (experimental physics and industrial control system) and CSS (control system studio).MethodsFirstly, the direct beam was searched and targeted using slit blades scanning, and then beam center was automatically optimized according to the single-objective and multi-objective optimization methods of genetic algorithm, the calibration is not completed until an optimal scattering background image is obtained.ResultsThe results show that the automatic beamline calibration system can complete the motors optimization of slits and beamstop in 30 min, much faster than manual operation.ConclusionsProposed automatic calibration system simplifies the optical path optimization of experimental station and improves the automation of the SAXS beamline station at SSRF.

Graphene quantum dots (GQDs) with ultrafine particle size and centralized distribution have advantages of small size, narrow size distribution and large specific surface area, which make it be better applied in bioimaging, drug delivery and so on. In our research, we used graphite irradiated by gamma-rays to successfully prepare GQDs with ultrafine particle size, narrow size distribution and high quantum yields through solvothermal method. Vacancy defects, pentagon-heptagon defects and interstitial defects were introduced to graphite structure after irradiation, which caused the abundance and concentrated distribution of defects. The defects generated by irradiation could damage the lattice structure of graphite to make it easy for introduction of C-O-C inside graphite sheets. The oxygen-containing functional groups in graphene oxide (GO) increased and centrally distributed after irradiation in graphite, especially for C-O-C group, which were beneficial for cutting of GO and grafting of functional groups in GQDs. Therefore, average size of GQDs was successfully reduced to 1.43 nm and concentrated to 0.6-2.4 nm. After irradiation in graphite, the content of carbonyl and C-N in GQDs had a promotion, which suppressed non-radiative recombination and upgraded the quantum yields to 13.9%.

The BL19U2 at the Shanghai Synchrotron Radiation Facility is a small-angle X-ray scattering beamline dedicated to structural studies pertaining to biological macromolecules in solution. The beamline has been officially opened to users in March 2015, and since then, a series of technological innovations has been developed to optimize beamline performance, thereby significantly improving the data collection efficiency and broadening the application scope of biological small-angle X-ray scattering. BL19U2 is ideal for the high-throughput screening of weakly scattered proteins, protein assemblies, nucleic acids, inorganic nanomaterials, and organic drug molecules. This paper describes the design and overview of the BL19U2 beamline. Versatile sample environments at the experimental station and some recent scientific highlights are presented.

A method based on the combination of in situ small-angle X-ray scattering (SAXS) and reactive molecular dynamics (MD) simulation is proposed to investigate the nucleation and initial growth of nanosilica. The formation and significant growth of silica nuclei within 1 s can be observed using in situ SAXS in a custom-designed sample cell. Meanwhile, reactive MD simulation confirms that the nucleation and initial growth take place over a very short time period and quantitatively describes the morphology of the formed particles. Both the experimental and simulation methods reveal changes in the particle size and number. A sudden increase in particle size is observed in the experiment, which corresponds to a decrease in particle number, indicating the transformation of the growth mode from ortho-silicic acid attachment to particle coalescence. The simulation snapshots also captures the process of particle coalescence, confirming the existence of this growth mode. The effects of the synthesis conditions, including temperature, sodium silicate concentration, and pH value, are studied and discussed in detail. The results show that the combination of in situ SAXS and reactive MD simulation is a useful method that provides detailed information on the preparation of precipitated silica and its regulatory mechanism.

Investigating the evolution of the hierarchical crystalline structure in the injection-molded polymer is instructive to better understand the process-structure relationship, which is critical for the design and manufacture of polymeric products with high performance. A nondestructive and quantitative method based on small-angle X-ray scattering microtomography (SAXS-CT) was developed to reveal the three-dimensional distribution and evolution of the hierarchical crystalline structure in injectionmolded polylactide (PLA). Spatial distributions of the oriented lamella and morphological parameters in the bulk PLA parts with different shear durations have been successfully mapped and quantitatively analyzed, which were further confirmed by scanning electronic microscopy. The effect of oscillation shear flow on the evolution of the hierarchical crystalline structure has been revealed successfully. The method based on SAXS-CT may provide a reliable tool for the establishment of the relationship between the process technology and the inner structure of the injection-molded polymer.

A novel thieno[3,4-b]thiophene-based donor polymer PTBTz-2 was used to construct ternary organic solar cells with two classical acceptors 3,9-bis(2-methylene-(3-(1,1-dicyano-methylene)-indanone)-5,5,11,11-tetrakis-(4-hexylphenyl)-dithieno[2,3-d:2',3'-d']-s-indaceno[1,2-b:5,6-b']dithiophene) (ITIC) and PC71BM. After the optimization of the donor-to acceptor weight ratio, a better match of the absorption spectrum and a high short circuit current density of 20.75 mA cm(-2) are obtained. The power conversion efficiency is improved to 11.26 from 10.43% after 35% PC71BM was added. The crystal structure data obtained by grazing-incidence wide-angle X-ray scattering gives a clearer picture that increase in the crystal correlation length of a donor polymer on the out-of-plane direction while decrease in the pi-pi stacking distances as the third phase of PC71BM was added. The added acceptor not only affects the structure character of the donor but also enhances the crystallization of the second acceptor ITIC on the in-plane direction. Homogeneous phase separation with a periodic distribution of donor and acceptor was observed by grazing incidence small-angle X-ray scattering as 35% PC71BM was added. Atomic force microscopy and transmission electron microscopy clearly demonstrated that a bicontinuous interpenetrating network between donors and acceptors was formatted. Our work demonstrates how to improve the photovoltaic device performance in the blend films by the added third phase from the nanomorphology and microscopic mechanism.