E01-JEM ARM 200CF
E02-JEM ARM 300CF
I18-Microfocus Spectroscopy
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N.
Topping
,
J. C.
Bridges
,
L. J.
Hicks
,
L.
Petera
,
C. S.
Allen
,
J.
Ryu
,
D. G.
Hopkinson
,
M.
Danaie
,
L.
Blase
,
F. M.
Willcocks
,
G.
Douglas
,
H. G.
Changela
,
T.
Noguchi
,
T.
Matsumoto
,
A.
Miyake
Diamond Proposal Number(s):
[30752, 31953, 32874, 35976, 29615, 31641, 35046]
Open Access
Abstract: A correlative multi-technique approach, including electron microscopy and X-ray synchrotron work, has been used to obtain both structural and compositional information of a sulfur-bearing serpentine identified in several carbonaceous chondrites (Winchcombe CM2, Aguas Zarcas CM2, Ivuna CI, and Orgueil CI), and in Ryugu samples returned by the Hayabusa2 mission. S-K edge X-ray absorption spectroscopy was used to determine the oxidation state of sulfur in the serpentine in all samples except Ryugu. The abundance of this phase varies across these samples, with the largest amount in Winchcombe; ~12 vol% of phyllosilicates are identified as sulfur-bearing serpentine characterized by ~10 wt% SO3 equivalent. HRTEM studies reveal a d001-spacing range of 0.64–0.70 nm across all sulfur-bearing serpentine sites, averaging 0.68 nm, characteristic of serpentine. Sulfur-serpentine has variable S6+/ΣStotal values and different sulfur species dependent on specimen type, with CM sulfur-bearing serpentine having values of 0.1–0.2 and S2− as the dominant valency, and CIs having values of 0.9–1.0 with S6+ as the dominant valency. We suggest sulfur is structurally incorporated into serpentine as SH− partially replacing OH−, and trapped as SO42− ions, with an approximate mineral formula of (Mg Fe2+ Fe3+ Al)2-3(Si Al)2O5(OH)5-6(HS−)1-2(SO4)2−0.1-0.7. We conclude that much of the material identified in previous studies of carbonaceous chondrites as TCI-like or PCPs could be sulfur-bearing serpentine. The relatively high abundance of sulfur-bearing serpentine suggests that incorporation of sulfur into this phase was a significant part of the S-cycle in the early Solar System.
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Nov 2025
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E02-JEM ARM 300CF
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Diamond Proposal Number(s):
[16967, 37411]
Open Access
Abstract: Atomic-scale wetting governs material formation at the nanoscale but remains poorly understood under confinement, where classical capillarity models fail. The growth of metallic nanowires within multi-wall carbon nanotubes (MWCNTs) exemplifies this challenge, requiring precise control over wetting, nucleation, and vapour-phase condensation. Here we show that nanowire formation proceeds through a two-stage mechanism: curvature-driven nucleation at open tube ends followed by capillary-driven elongation sustained by continuous vapour condensation. Using in situ atomic-resolution transmission electron microscopy (ARTEM) coupled with a deep learning convolutional neural network (CNN) capable of classifying liquid, solid and intermediate SnxO phase transitions, we directly capture the cascade of thermally induced nanowire growth within CNTs. Growth requires a wetting interface (contact angle, θ <90°) between liquid SnxO and the nanotube wall—conditions not described by Kelvin or Lucas–Washburn models. These results establish a predictive framework for vapour-phase nanowire encapsulation, linking nanoscale wetting dynamics to the fabrication of advanced nanomaterials.
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Nov 2025
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E02-JEM ARM 300CF
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Diamond Proposal Number(s):
[39072]
Open Access
Abstract: Electrochemical impedance spectroscopy (EIS) is widely used to probe the solid electrolyte interphase (SEI) under realistic conditions, without causing damage to its structure. However, the models and experimental conditions often raise concerns about the reliability of the results. In this work, we present an extensive EIS study of lithium metal in the model electrolyte lithium bis(fluorosulfonyl)imide in tetraglyme, analyzing the system at equilibrium as a function of time, temperature, and salt concentration using a setup designed to minimize artifacts. We apply information theory to determine the number of independent degrees of freedom and constrain the number of Voigt elements used in fitting. Our analysis reveals strong correlations among processes, warranting caution when assigning physical meaning. X-ray photoelectron spectroscopy and 4D-scanning transmission electron microscopy measurements are used to support the interpretation and provide complementary insights into the chemical nature of the interphase. The unique and extensive dataset we have collected, comprising over 12000 highly reproducible impedance spectra, will serve as a valuable resource to the community for further analysis and for supporting additional modeling and experimental efforts.
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Nov 2025
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E01-JEM ARM 200CF
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Diamond Proposal Number(s):
[35899]
Open Access
Abstract: Encapsulins are microbial protein nanocompartments that spatially organize and sequester specific biochemical processes, including iron storage. While their protein shells have been extensively characterized, the composition and structure of their mineral cores remain less understood. Here, we use bright field transmission electron microscopy (BF TEM), high-angle annular dark-field scanning TEM (HAADF STEM), energy-dispersive X-ray (EDX), and electron energy-loss spectroscopy (EELS) in STEM to characterize the iron-containing mineral granules within the Myxococcus xanthus encapsulin system at near atomic resolution. We find that the internal nanoparticles are smaller (~2 nm) and more numerous (up to ~2200 per encapsulin) than previously reported. These nanoparticles are typically amorphous and have a composition consistent with FePO4 (measured Fe:P ratio of ≈1:1.2). Each encapsulin contains on average ~8500 iron atoms, corresponding to a volumetric density of 2.1 atoms/nm3. Phosphorus incorporation inhibits crystallization, whereas growth in phosphorus-free media leads to the formation of nano-crystalline goethite [α-FeO(OH)].
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Nov 2025
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B07-C-Versatile Soft X-ray beamline: Ambient Pressure XPS and NEXAFS
B18-Core EXAFS
E02-JEM ARM 300CF
I11-High Resolution Powder Diffraction
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Mengqi
Duan
,
Shuai
Guo
,
Wentian
Niu
,
Hangjuan
Ren
,
Thomas
Dittrich
,
Dongpei
Ye
,
Lucy
Saunders
,
Sarah
Day
,
Veronica
Celorrio
,
Diego
Gianolio
,
Peixi
Cong
,
Robert S.
Weatherup
,
Robert
Taylor
,
Songhua
Cai
,
Yiyang
Li
,
Shik Chi Edman
Tsang
Diamond Proposal Number(s):
[35749, 35750, 35961, 37117]
Open Access
Abstract: Two-dimensional layered perovskite oxides have emerged as promising photocatalysts for solar-driven hydrogen evolution. Although doping has been widely employed to enhance photocatalytic performance, its role in modulating the electronic structure and the local chemical environment of these materials remains poorly understood. Here in this study, we investigate the codoping of Rh and La into exfoliated nanosheets of the Dion–Jacobson perovskite KCa2Nb3O10 to enhance photocatalytic hydrogen evolution reaction (HER) activity. A substantial increase in H2 evolution rate, from 12.3 to 69.0 μmol h–1, was achieved at an optimal doping level of 0.2 wt % Rh and 1.3 wt % La. Comprehensive structural and spectroscopic analyses, including synchrotron techniques and high-resolution microscopy, revealed that Rh3+ substitutes Nb5+ to introduce shallow 4d acceptor states that mediate charge separation, while La3+ substitutes Ca2+, compensates for aliovalent charge imbalance, and modulates local lattice distortions and oxygen vacancy formation. This codoping strategy enhances charge carrier lifetime and separation efficiency through a trap-mediated mechanism. The observed volcano-shaped activity trend highlights a narrow compositional window, where electronic and structural factors are optimally balanced. These findings establish a mechanistic foundation for defect engineering in layered perovskites and offer a pathway for the rational design of photocatalysts.
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Oct 2025
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E02-JEM ARM 300CF
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Diamond Proposal Number(s):
[16952]
Open Access
Abstract: Atomic resolution imaging is key to understanding thin film growth and how a particular set of conditions influences properties. Whilst such imaging in the scanning transmission electron microscope (STEM) has had a transformative impact in nanoscience, it forms projection images and provides no direct information about displacements perpendicular to the image plane. In this article, we show that it is possible to make atomic resolution maps of the direction and magnitude of La displacements at ∼30∘ to the imaging plane in a La2CoMnO6 thin film on (111) LSAT (LaAlO3−La(Sr,Ta)O3) using a four-dimensional STEM (4DSTEM) methodology. This reveals that the La modulation lies preferentially in the interface plane, and is strongly suppressed close to the epitaxial interface, and further reveals how the modulation varies with distance from the interface with unit cell resolution. These details would be completely invisible to all prior techniques in electron microscopy and this sheds light on why this particular substrate in this orientation best promotes double perovskite cation ordering, and the consequent optimal magnetic ordering for this thin film system. The approach used herein of fitting atomic resolution 4DSTEM data to determine crystal parameters opens the door for a new era of atomic-resolution crystallography.
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Sep 2025
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E02-JEM ARM 300CF
I09-Surface and Interface Structural Analysis
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Benedikt P.
Klein
,
Matthew A.
Stoodley
,
Joel
Deyerling
,
Luke A.
Rochford
,
Dylan B.
Morgan
,
David G.
Hopkinson
,
Sam
Sullivan-Allsop
,
Henry
Thake
,
Fulden
Eratam
,
Lars
Sattler
,
Sebastian M.
Weber
,
Gerhard
Hilt
,
Alexander
Generalov
,
Alexei
Preobrajenski
,
Thomas
Liddy
,
Leon B. S.
Williams
,
Mhairi A.
Buchan
,
Graham A
Rance
,
Tien-Lin
Lee
,
Alex
Saywell
,
Roman
Gorbachev
,
Sarah J.
Haigh
,
Christopher S.
Allen
,
Willi
Auwärter
,
Reinhard
Maurer
,
David A.
Duncan
Diamond Proposal Number(s):
[25379, 30875, 31695, 31165, 33709]
Open Access
Abstract: Chemical vapour deposition enables large-domain growth of ideal graphene, yet many applications of graphene require the controlled inclusion of specific defects. We present a one-step chemical vapour deposition procedure aimed at retaining the precursor topology when incorporated into the grown carbonaceous film. When azupyrene, the molecular analogue of the Stone–Wales defect in graphene, is used as a precursor, carbonaceous monolayers with a range of morphologies are produced as a function of the copper substrate growth temperature. The higher the substrate temperature during deposition, the closer the resulting monolayer is to ideal graphene. Analysis, with a set of complementary materials characterisation techniques, reveals morphological changes closely correlated with changes in the atomic adsorption heights, network topology, and concentration of 5-/7-membered carbon rings. The engineered defective carbon monolayers can be transferred to different substrates, potentially enabling applications in nanoelectronics, sensorics, and catalysis.
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Sep 2025
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E01-JEM ARM 200CF
E02-JEM ARM 300CF
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Diamond Proposal Number(s):
[30463]
Open Access
Abstract: This study investigates the catalytic properties of nanoceria for the liquid-phase oxidation of aromatic and aliphatic alcohols using t-butyl hydroperoxide as an oxidant without the need for base or supported noble metals. The morphology, reducibility, and reversible H2 adsorption characteristics of ceria were comprehensively studied using X-ray diffraction, BET, HAADF-STEM, H2-TPR, H2-TPD, and X-ray photoelectron spectroscopy. Radical formation was interrogated by electron paramagnetic resonance (EPR) using dimethyl pyrrolidine N-oxide (DMPO) and N-tert-butyl-α-phenylnitrone (PBN) as spin traps, complemented by atomistic simulations to elucidate the influence of trap and radical adduct adsorption on the catalysts on radical abundance. The solvent played a critical role in enhancing the catalytic performance and carbon balance. The catalyst retained its structural integrity during the reaction in acetonitrile and could be reused for at least five consecutive runs. EPR analysis revealed that peroxyl radicals (tBu-OO•) were the predominant reactive species with no detectable formation of oxyl (tBu-O•) radicals, ruling out a Fenton-like catalytic mechanism in solution. Incorporating small amounts of Au (0.5–1.0 wt %) as Au(I) single atoms or clusters reduced the catalytic activity due to a decreased surface reducibility and reversible H2 adsorption despite an increased peroxyl radical formation. However, Au doping did not alter the product distribution. Compared to a benchmark 0.3 wt % Au/TS-1 catalyst, nanoceria achieved a 60% cost reduction and an E-factor of 0.08 (vs 0.2–1.3 for 0.3 wt % Au/TS-1) at equivalent acid production rates, highlighting the economic and environmental benefits.
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Aug 2025
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E02-JEM ARM 300CF
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Diamond Proposal Number(s):
[35743]
Open Access
Abstract: Integrated Centre-of-Mass (iCOM) is a widely used phase-contrast imaging method based on Centre-of-Mass (COM), which makes use of a 4D Scanning Transmission Electron Microscopy (STEM) dataset using an in-focus probe. In this paper, we introduce a novel approach that combines Single-Side Band (SSB) ptychography with COM and iCOM, termed Side Band masked Centre-of-Mass (SBm-COM) and integrated Centre-of-Mass (SBm-iCOM) which is applicable to weak-phase objects. This method compensates for residual aberrations in 4DSTEM datasets while also reducing the noise contribution up to the resolution limit. The aberration compensation and noise filtering features make the SBm-(i)COM suitable for samples that are difficult to focus or those that require minimal electron fluence. SBm-iCOM transfers the same information as SSB ptychography but results in an intrinsic transfer function that enhances low-frequency information.
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Aug 2025
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E02-JEM ARM 300CF
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Stefan
Heiserer
,
Natalie
Galfe
,
Michael
Loibl
,
Maximilian
Wagner
,
Oliver
Hartwig
,
Simon
Schlosser
,
Silke
Boche
,
William
Thornley
,
Nick
Clark
,
Kangho
Lee
,
Tanja
Stimpel‐lindner
,
Cormac
Ó Coileáin
,
Josef
Kiendl
,
Sarah J.
Haigh
,
George J.
De Coster
,
Georg S.
Duesberg
,
Paul
Seifert
Diamond Proposal Number(s):
[30728]
Open Access
Abstract: 2D layered materials such as PtSe2 are prime candidates for next-generation micro- and nano-electro–mechanical systems (MEMS/NEMS), including piezoresistive sensors. However, due to difficulties in large-scale synthesis and the inherent drawbacks associated with mechanical transfer of 2D material films, scalable NEMS production remains challenging. In this work, we report a fabrication route for free-standing, as-grown 2D material channels of PtSe2 with controlled dimensions, avoiding a mechanical film transfer. The free-standing devices provide a universal platform for strain engineering of 2D materials because tension can be easily controlled by application of a back-contact voltage. Moreover, the piezoresistivity of PtSe2, together with the possibility of wafer-scale synthesis at back-end-of-line compatible growth temperatures, make it ideally suited for scalable incorporation into integrated circuits. Our measurements show that the material properties can be tuned via strain, which offers pathways for classically non-gateable materials in electronic and photonic devices. Finite element simulations of representative free-standing films elucidate the nano–mechanical properties of large-scale-grown, polycrystalline 2D materials under tensile strain and demonstrate the influence of polycrystallinity on the optical and electrical behavior.
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Aug 2025
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