E02-JEM ARM 300CF
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Sam
Sullivan-Allsop
,
Nick
Clark
,
Wendong
Wang
,
Rongsheng
Cai
,
William
Thornley
,
David G.
Hopkinson
,
James G.
Mchugh
,
Ben
Davies
,
Samuel
Pattisson
,
Nicholas F.
Dummer
,
Rui
Zhang
,
Matthew
Lindley
,
Gareth
Tainton
,
Jack
Harrison
,
Hugo
De Latour
,
Joseph
Parker
,
Joshua
Swindell
,
Eli G.
Castanon
,
Amy
Carl
,
David J.
Lewis
,
Natalia
Martsinovich
,
Christopher S.
Allen
,
Mohsen
Danaie
,
Andrew J.
Logsdail
,
Vladimir
Fal’ko
,
Graham J.
Hutchings
,
Alex
Summerfield
,
Roman
Gorbachev
,
Sarah J.
Haigh
Diamond Proposal Number(s):
[33252, 35552]
Abstract: The structure and dynamics of adsorbed atoms (adatoms) at solid-liquid interfaces determine the performance of advanced catalysts, electrochemical devices, molecular separation technologies, and metal extraction from waste streams. However, in situ investigations of atomically dispersed metals in various chemical environments have been prevented by insufficient imaging resolution and solvent incompatibility. In this study, we combined a specimen design that provides atomic resolution in liquid-phase electron microscopy with deep learning–enabled analysis to explore the interactions between gold adatoms, graphite support, and the solvent collectively. We tracked the locations of >106 graphite-supported gold adatoms, dimers, and larger clusters in five solvents. Although their initial atomic dispersion was determined by the solvent polarity, fast drying kinetics at low temperature was required for optimizing catalytic performance.
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Apr 2026
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E02-JEM ARM 300CF
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Diamond Proposal Number(s):
[37041, 56733]
Open Access
Abstract: 2D Prussian blue and its analogues hold great promise for applications in catalysis, energy conversion, sensing, and memory devices, thanks to their open frameworks, surface activity, and directional ion transport. However, synthesizing high-quality and large-area 2D films remains a major challenge. Here, we present a robust and scalable liquid-liquid interfacial synthesis that enables the formation of continuous, 2D flakes of Prussian blue (Fe3+[Fe2+(CN)6]0.75) with tunable thicknesses from ∼2 nm to several hundred nanometers. The controlled reduction of [Fe3+(CN)6]3− to [Fe2+(CN)6]4− enables slow, directed growth of 2D-FeFe layers. Unlike films formed from nanoparticles, this method yields high-quality flakes suitable for integration into devices. As a demonstration, we incorporated these films into Ag filament-based electrochemical metallization memristors. The 2D-FeFe devices ≥50 nm thick exhibited reliable bipolar electrical switching, with high Roff/on ratios (∼106), >6 h retention, and stability over 150 cycles. Strikingly, switching was observed across 1.5 µm lateral gaps, far exceeding conventional silver filament formation distances, highlighting the superior ion transport and structural integrity of these 2D frameworks. This scalable approach to 2D Prussian blue, which has the potential to be extended to other related coordination polymers, offers exciting opportunities beyond memristors, enabling integration into technologies where thin-film compatibility, directional ion transport, and high surface activity are critical, such as catalysis, energy storage, and neuromorphic computing.
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Jan 2026
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E02-JEM ARM 300CF
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Diamond Proposal Number(s):
[33430]
Open Access
Abstract: The electrochemical reduction of N2 in aqueous media and ambient conditions would present a great advancement in the defossilization of the fertilizer and energy sector, if the obstacles to this technology were not as significant as they are at present. Some recent reports have raised doubts about whether the electrochemical nitrogen reduction reaction (eNRR) is even possible in aqueous media. Herein, a type of metal-organic framework (MOF)-derived Fe and Zn single atom catalyst for the eNRR is revisited, which has been reported more than once in recent literature to be active for eNRR in aqueous media. Electrochemical measurements reported here show the inactivity of the investigated iron-based catalysts for the eNRR in neutral aqueous media when contaminations are excluded. In stark contrast, the reduction of NOx contamination to ammonia is shown to be a possible reason for false positive results. The reduction of nitrate to ammonia (NO3-RR) is itself an emerging field of research that investigates the conversion of nitrate from wastewater to ammonia. For the NO3-RR, the MOF-derived catalysts show good activity and selectivity, which depends on the iron site density in the catalyst. An ammonia yield of 19.1 mg h−1 mgcat−1 at −1.0 V versus RHE and a maximum faradaic efficiency (FE) of 100% at −0.9 V versus RHE is achieved.
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Dec 2025
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E02-JEM ARM 300CF
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Evan David Innes
Tillotson
,
William
Thornley
,
William
Talbott
,
Alexander S.
Eggeman
,
Daria
Kriuchkova
,
Sam
Sullivan-Allsop
,
Matthew
Smith
,
Xuzhao
Liu
,
Ashley
Slattery
,
Pei Lay
Yap
,
Dusan
Losic
,
Zhun
Xu
,
Huan
Wang
,
Jim
Ciston
,
Alexander
Rakowski
,
Stephanie M.
Ribet
,
Benjamin H
Savitzky
,
Manfred Erwin
Schuster
,
Christopher S.
Allen
,
Danielle
Douglas-Henry
,
Valeria
Nicolosi
,
Andrew
Herzing
,
Jacques
O'Connell
,
Ezra J.
Olivier
,
Jan
Neethling
,
Yichao
Zou
,
Ercin Cagan
Duran
,
Rongsheng
Cai
,
Duc-The
Ngo
,
Roman
Gorbachev
,
Jonas
Haas
,
Michael
Schlegel
,
Jannik C.
Meyer
,
Alba
Centeno
,
Amaia
Pesquera
,
Amaia
Zurutuza
,
Sungsu
Kang
,
Jungwon
Park
,
Ivan
Erofeev
,
Utkur
Mirsaidov
,
Colin
Ophus
,
Christian
Rentenberger
,
Thomas
Waitz
,
Jani
Kotakoski
,
Abhijit
Roy
,
Raul
Arenal
,
Andrew
Pollard
,
Sarah
Haigh
Diamond Proposal Number(s):
[29951]
Open Access
Abstract: Standardisation of data collection and analysis is essential to enable commercialisation of 2D materials in a wide range of technologies. Selected area electron diffraction (SAED) in the transmission electron microscope (TEM) is one of the key methods for distinguishing monolayer from bilayer and few-layer graphene by comparing the 1st and 2nd order diffraction spot intensities. Yet there are many factors that can affect the reliability of data collection and interpretation, causing the measurement of monolayer samples to deviate from the literature boundary condition of I{-2110}/I{1-100}<1 for monolayer graphene. Here we present the results of a large interlaboratory SAED comparison study, where 15 international laboratories measured and analysed nominally identical samples of chemical vapour deposited (CVD) graphene. Large variations were observed in the measured ratios of diffraction spot intensities, with the largest variance associated with poor quality SAED data resulting from poor specimen handling and storage. To inform the reliable determination of monolayer thickness from SAED patterns we provide a description of best practice for specimen handling, TEM operation, data collection and analysis. This work was undertaken within VAMAS Technical Working Area (TWA) 41: Graphene and related 2D materials - Project 9, the results of which have been directly incorporated into ISO/TS 21356-2 for the characterisation of graphene sheets. We find that when this methodology is followed, monolayer graphene can be distinguished from bilayer or thicker material with high confidence where analysis of a single SAED pattern gives I{-2110}/I{1-100}<1.2, even in the absence of precise specimen tilting.
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Dec 2025
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E01-JEM ARM 200CF
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Diamond Proposal Number(s):
[33481]
Open Access
Abstract: A novel heterostructured hexagonal-boron nitride (h-BN) flake-coating on multi-wall carbon nanotubes (MWCNT/BN) is reported and synthesized by chemical vapor deposition (CVD). Comprehensive characterization using X-ray photoelectron spectroscopy (XPS) and scanning transmission electron microscopy (STEM), combined with electron energy loss spectroscopy (EELS), revealed the atomic structure and growth mechanism, which is further validated by molecular dynamics simulations. The resulting MWCNT/BN structure comprises three distinct layers: an inner carbon nanotube (CNT) core, coaxial BN nanotubes (BNNTs) surrounding the CNT core, and outer BN flakes extending from the BNNTs. We propose that BN layers first form coaxial BNNTs on the CNT surface; as deposition proceeds, BN accumulation generate in-plane and out-of-plane compressive stresses in the h-BN layers. When these stresses exceed a critical threshold, local buckling or cracking occurs, BN flakes emerge and grow further. This work elucidates, for the first time, the formation mechanism of BN nanoflakes on MWCNTs and confirms that the structure is a van der Waals heterostructure. The approach also offers a new route for synthesizing coaxial MWCNT@BN with only a few h-BN layers. Notably, the BN flake coatings provide efficient phonon transport pathways and a large surface area, making this heterostructure highly promising for applications in thermal dissipation.
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Dec 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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B07-C-Versatile Soft X-ray beamline: Ambient Pressure XPS and NEXAFS
E01-JEM ARM 200CF
I20-Scanning-X-ray spectroscopy (XAS/XES)
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Lu
Chen
,
Xuze
Guan
,
Zhangyi
Yao
,
Shusaku
Hayama
,
Matthijs A.
Van Spronsen
,
Burcu
Karagoz
,
Georg
Held
,
David G.
Hopkinson
,
Christopher S.
Allen
,
June
Callison
,
Paul J.
Dyson
,
Feng Ryan
Wang
Diamond Proposal Number(s):
[30576, 31867, 32996]
Open Access
Abstract: Tuning the electronic properties of nanocatalysts via doping with monodispersed hetero-metal atoms is an effective method used to enhance catalytic properties. Doping CuO nanoparticles with monodispersed Co atoms using different reductants affords catalysts (CoBCu/Al2O3 and CoHCu/Al2O3) with strikingly different electronic structures. Compared to CoHCu/Al2O3, the CuO nanoparticles in CoBCu/Al2O3 have longer and weaker Cu-O bonds, with a lower 1s → 4pz antibonding transition and higher 4p → 1s bonding transition (as demonstrated from HERFD-XANES and valence-to-core X-ray emission spectroscopy). The weaker Cu-O bonds in CoBCu/Al2O3 lead to superior redox activity of the CuO nanoparticles, evidenced from operando XAFS and in-situ near ambient pressure-near edge X-ray absorption fine structures studies. Such superior redox properties of CuO in CoBCu/Al2O3 result in a much reduced activation energy of CoBCu/Al2O3 compared to CoHCu/Al2O3 (40.0 vs. 63.5 kJ/mol), thus leading to an enhancement in catalytic performance in the selective catalytic oxidation of NH3 to N2.
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Oct 2025
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Open Access
Abstract: Multi-slice electron ptychography has attracted significant interest in recent years, thanks to notable experimental successes in ultra-high resolution, depth-resolved imaging of atomic structure. However, the theoretical dependence of depth of field on experimental parameters is not well understood. In this paper we use simulated data to compare the depth of field of through focal annular-dark field and multi-slice electron ptychography over a range of acceleration voltages and convergence angles. We show that at both low convergence angle and at low electron energy, multi-slice ptychography has significantly improved depth of field over through focal ADF imaging.
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Oct 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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