I15-1-X-ray Pair Distribution Function (XPDF)
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Diamond Proposal Number(s):
[345501]
Open Access
Abstract: The Ga₂S₃–Sb₂S₃ quasi-binary system has been investigated for its potential to yield stable chalcogenide glasses with tailored thermal and structural properties. Using melt-quenching techniques, a series of (Ga₂S₃)ₓ(Sb₂S₃)₁₋ₓ compositions (0.0 ≤ x ≤ 0.5) were synthesized, and their glass-forming domain was mapped. The latter extends up to approximately x ≤ 0.40, as confirmed by X-ray diffraction and DSC analyses, with the x = 0.4 composition exhibiting a glass-ceramic character. Density measurements, combined with calculations of molar volume and packing density, revealed a continuous structural densification as Ga₂S₃ content increased. Differential scanning calorimetry showed an increase in glass transition temperature (Tg), with the best thermal stability observed for x = 0.2, as assessed by the Hruby criterion. Electrical conductivity measurements demonstrated thermally activated behaviour following the Arrhenius law, with maximum activation energy also centred at x = 0.2. Raman spectroscopy and DFT modelling were used to decipher the structural contributions of Sb–S and Ga–S bonding. The emergence of vibrational modes characteristic of Ga-based structural units, especially beyond x > 0.2, suggests a structural reorganization from Sb-centred pyramidal units to Ga-centred tetrahedral. This was corroborated by high-energy X-ray diffraction, which showed significant changes in intermediate-range order with increasing Ga content, particularly in the first sharp diffraction peak and partial coordination environments.
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Apr 2026
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I15-1-X-ray Pair Distribution Function (XPDF)
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Georgina P.
Robertson
,
Emily V.
Shaw
,
Florencia A.
Son
,
Celia
Castillo-Blas
,
Bethan
Turner
,
James M. A.
Steele
,
Christopher A.
O'Keefe
,
Kirill A.
Lomachenko
,
Angelika D.
Rosa
,
Daniel J. M.
Irving
,
Michael F.
Thorne
,
Alice M.
Bumstead
,
Omar K.
Farha
,
Lauren N.
Mchugh
,
David A.
Keen
,
Philip A.
Chater
,
Thomas D.
Bennett
Diamond Proposal Number(s):
[20038, 29957]
Abstract: Defect engineering of metal–organic frameworks (MOFs) has been shown to impact many properties of these porous structures, including affecting the accessible pore volume as well as introducing additional active sites to modify the catalytic activity of the frameworks. However, this defect engineering has previously primarily been carried out through synthesis-based methods. Ball-milling of the frameworks presents an alternative method for the introduction of defects, which has not been largely investigated for its effects on catalysis. The complex pressure states experienced during milling result in property changes, both enhancing and diminishing defect accessibility, necessitating a detailed investigation. This work characterizes three Zirconium-based MOFs (UiO-66, MOF-808, and NU-1000), using total scattering X-ray diffraction, infrared spectroscopy, and thermal analysis to investigate their collapse and defect introduction during all stages of ball-milling. It then assesses the utility of ball-milling UiO-66 to different extents as a method for improving catalytic abilities within two reactions, the formation of propargylamine, and the conversion of glucose to fructose. The mechanical amorphization of UiO-66 led to either an increase or a decrease in catalytic ability depending on the milling time and the reaction investigated.
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Feb 2026
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I15-1-X-ray Pair Distribution Function (XPDF)
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Danial
Farooq
,
Lucy
Costley-Wood
,
Sebastian
Stockenhuber
,
Antonis
Vamvakeros
,
Stephen
Price
,
Lisa
Allen
,
Jakub
Drnec
,
James
Paterson
,
Mark
Peacock
,
Daniel J. M.
Irving
,
Philip A.
Chater
,
Andrew M.
Beale
Diamond Proposal Number(s):
[30639]
Open Access
Abstract: The transition to net-zero emissions hinges on circular economy strategies that valorize waste and enhance resource efficiency. Among X-to-liquid (XTL) technologies, the Fischer-Tropsch (FT) process stands out for converting biomass, waste, and CO2 into hydrocarbons and chemicals, especially when powered by renewable hydrogen. Cobalt-based catalysts are preferred in FT synthesis due to their efficiency and CO2 tolerance, yet their catalytic performance is closely tied to their polymorphic structures─face-centered cubic (FCC), hexagonal close-packed (HCP), and stacking-faulted intergrowths thereof. HCP cobalt has been shown to exhibit high activity and selectivity for higher hydrocarbons and oxygenates, particularly when transformed into cobalt carbide (Co2C), which forms more readily at low H2/CO ratios. This study presents a quantitative analysis of cobalt polymorphs and stacking faults in Mn-promoted Co/TiO2 FT catalysts from in situ powder X-ray diffraction (XRD) data and X-ray Diffraction Computed Tomography (XRD-CT) data from spent catalysts in order to obtain a more complete correlation of structural features with catalytic performance. By modeling stacking fault probabilities using supercell simulations, the proportion of faulted FCC and HCP domains was determined across varying Mn loadings (0–5%). Increased Mn loading was found to decrease stacking faults in the FCC phase while increasing them in HCP, promoting the formation of HCP domains and ultimately Co2C under reaction conditions. Notably, the 3% Mn-loaded sample showed a marked rise in HCP content and Co2C formation, correlating with the highest observed alcohol and olefin selectivity. These findings highlight a critical structure–function relationship: Mn facilitates a transformation from FCC to HCP and then to Co2C, this final transition driven by similar stacking sequences and metal–support interactions. The findings show that Mn promotion not only stabilizes smaller Co particles and enhances its dispersion, but also modulates the distribution of Co polymorphs and stacking faults, leading to altered catalytic behavior. This highlights the importance of stacking fault characterization for optimizing FT catalyst design and performance, and suggests pathways to more efficient and selective carbon-neutral fuel production through engineered polymorphic and interfacial structures.
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Feb 2026
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I12-JEEP: Joint Engineering, Environmental and Processing
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Emily C.
Giles
,
Abbey
Jarvis
,
Pierrot S.
Attidekou
,
Kieran
O'Regan
,
Rosie
Madge
,
Alexander T.
Sargent
,
Beatrice
Browning
,
Anton
Zorin
,
Roberto
Sommerville
,
Alex J.
Green
,
Stefan
Michalik
,
Philip A.
Chater
,
Daniel
Reed
,
Emma
Kendrick
,
Laura L.
Driscoll
,
Peter
Slater
,
Phoebe K.
Allan
,
Paul
Anderson
,
Luke
Sweeney
Open Access
Abstract: Understanding the degradation of large format lithium-ion pouch cells – critical for electric vehicle applications – is vital to extend their lifetime and allow potential second-life application. Here, the impact on capacity fade and material degradation in two end-of-life cells, which were additionally subjected to accelerated aging to mimic extended use in second-life applications, were examined using powder synchrotron X-ray diffraction, Raman spectroscopy and electrochemical impedance spectroscopy, complemented by detailed post mortem analyses. The dominant mechanism of capacity loss under these conditions was found to be lithium inventory depletion, driven by processes such as electrolyte decomposition, lithium plating and solid electrolyte interphase growth. Structural changes in the graphite anode, including amorphization and reduced active material, were more pronounced under severe overcharging conditions. The blended cathode showed lithium inventory loss in both phases, but 92–94% capacity recovery was observed on subsequent cycling in half cells vs Li, illustrating its robustness, with little structural degradation observed. The finding that electrolyte degradation/loss in these cells was a more critical contributor to cell degradation toward the knee-point than electrode active material degradation/loss indicates that increasing – or replenishing – the electrolyte content could be a strategy to extend the usable life of such cells.
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Nov 2025
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I15-1-X-ray Pair Distribution Function (XPDF)
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Adam F.
Sapnik
,
Philip A.
Chater
,
Dean S.
Keeble
,
John S. O.
Evans
,
Federica
Bertolotti
,
Antonietta
Guagliardi
,
Lise J.
Støckler
,
Elodie A.
Harbourne
,
Anders B.
Borup
,
Rebecca S.
Silberg
,
Adrien
Descamps
,
Clemens
Prescher
,
Benjamin D.
Klee
,
Axel
Phelipeau
,
Imran
Ullah
,
Kárel G.
Medina
,
Tobias A.
Bird
,
Viktoria
Kaznelson
,
William
Lynn
,
Andrew L.
Goodwin
,
Bo B.
Iversen
,
Celine
Crepisson
,
Emil S.
Bozin
,
Kirsten M. Ø.
Jensen
,
Emma E.
Mcbride
,
Reinhard B.
Neder
,
Ian
Robinson
,
Justin S.
Wark
,
Michał
Andrzejewski
,
Ulrike
Boesenberg
,
Erik
Brambrink
,
Carolina
Camarda
,
Valerio
Cerantola
,
Sebastian
Goede
,
Hauke
Höppner
,
Oliver S.
Humphries
,
Zuzana
Konopkova
,
Naresh
Kujala
,
Thomas
Michelat
,
Motoaki
Nakatsutsumi
,
Alexander
Pelka
,
Thomas R.
Preston
,
Lisa
Randolph
,
Michael
Roeper
,
Andreas
Schmidt
,
Cornelius
Strohm
,
Minxue
Tang
,
Peter
Talkovski
,
Ulf
Zastrau
,
Karen
Appel
,
David A.
Keen
Diamond Proposal Number(s):
[39017]
Open Access
Abstract: High-quality total scattering data, a key tool for understanding atomic-scale structure in disordered materials, require stable instrumentation and access to high momentum transfers. This is now routine at dedicated synchrotron instrumentation using high-energy X-ray beams, but it is very challenging to measure a total scattering dataset in less than a few microseconds. This limits their effectiveness for capturing structural changes that occur at the much faster timescales of atomic motion. Current X-ray free-electron lasers (XFELs) provide femtosecond-pulsed X-ray beams with maximum energies of ∼24 keV, giving the potential to measure total scattering and the attendant pair distribution functions (PDFs) on femtosecond timescales. We demonstrate that this potential has been realized using the HED scientific instrument at the European XFEL and present normalized total scattering data for 0.35 Å−1 < Q < 16.6 Å−1 and their PDFs from a broad spectrum of materials, including crystalline, nanocrystalline and amorphous solids, liquids and clusters in solution. We analyzed the data using a variety of methods, including Rietveld refinement, small-box PDF refinement, joint reciprocal–real-space refinement, cluster refinement and Debye scattering analysis. The resolution function of the setup is also characterized. We conclusively show that high-quality data can be obtained from a single ∼30 fs XFEL pulse for multiple different sample types. Our efforts not only significantly increase the existing maximum reported Q range for an S(Q) measured at an XFEL but also mean that XFELs are now a viable X-ray source for the broad community of people using reciprocal-space total scattering and PDF methods in their research.
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Sep 2025
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I15-1-X-ray Pair Distribution Function (XPDF)
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Maksim
Eremenko
,
Victor
Krayzman
,
Semen
Gorfman
,
Alexei
Bosak
,
Helen Y.
Playford
,
Philip A.
Chater
,
Bruce
Ravel
,
William J.
Laws
,
Feng
Ye
,
Arianna
Minelli
,
Bi-Xia
Wang
,
Zuo-Guang
Ye
,
Matthew G.
Tucker
,
Igor
Levin
Diamond Proposal Number(s):
[27040]
Open Access
Abstract: Relaxor ferroelectrics underpin high-performance actuators and sensors, yet the nature of polar heterogeneities driving their broadband dielectric response remains debated. Using a unified, multimodal structural refinement framework— simultaneously fitting complementary X-ray and neutron total scattering, X-ray absorption spectra, and diffuse scattering—we reconstruct 3D mesoscale polarization maps in the classic relaxor system PbMg1/3Nb2/3O3–PbTiO3. We uncover self-organized swirling polarization textures with half-skyrmion (meron) vortices, challenging models of independent polar nanoregions. These textures, characterized by smooth changes in the polarization direction, originate from overlapping volumes in which the projections of locally correlated polarization vectors onto each volume’s long axis share the same sign. Vortex cores correlate strongly with local charge and strain gradients imposed by compositional heterogeneities. In this work, our results suggest that chemical disorder, acting via depolarizing and strain fields, stabilizes topological vortex textures of the polarization field, offering a route for engineering new dielectric and ferroelectric functionalities.
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Aug 2025
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I15-1-X-ray Pair Distribution Function (XPDF)
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Diamond Proposal Number(s):
[29957]
Open Access
Abstract: The development of metal-organic framework (MOF) crystal-glass composites (CGCs) has been hindered by the scarcity of MOF glass matrices with low glass transition temperatures (Tgs). Here, we investigate a CGC consisting of a low-Tg MOF glass, (agZIF-UC-7) and UiO-66. Powder X-ray diffraction and stability tests in phosphate buffer saline solution showed UiO-66 was stabilised in the glass matrix. Additionally, the composite exhibited enhanced dye uptake and gas adsorption relative to agZIF-UC-7.
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Jul 2025
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I15-1-X-ray Pair Distribution Function (XPDF)
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Celia
Castillo-Blas
,
Montaña J.
García
,
Ashleigh M.
Chester
,
Matjaž
Mazaj
,
Shaoliang
Guan
,
Georgina P.
Robertson
,
Ayano
Kono
,
James M. A.
Steele
,
Luis
León-Alcaide
,
Bruno
Poletto-Rodrigues
,
Philip A.
Chater
,
Silvia
Cabrera
,
Andraž
Krajnc
,
Lothar
Wondraczek
,
David A.
Keen
,
Jose
Alemán
,
Thomas
Bennett
Diamond Proposal Number(s):
[29957]
Open Access
Abstract: Metal–organic framework (MOF) composites are proposed as solutions to the mechanical instability of pure MOF materials. Here, we present a new compositional series of recently discovered MOF–crystalline inorganic glass composites. In this case, formed by the combination of a photocatalytic titanium MOF (MIL-125-NH2) and a phosphate-based glass (20%Na2O–10%Na2SO4–70%P2O5). This new family of composites has been synthesized and characterized using powder X-ray diffraction, thermal gravimetric analysis, differential scanning calorimetry, scanning electron microscopy, and X-ray total scattering. Through analysis of the pair distribution function extracted from X-ray total scattering data, the atom–atom interactions at the MOF–glass interface are described. Nitrogen and carbon dioxide isotherms demonstrate good surface area values despite the pelletization and mixing of the MOF with a dense inorganic glass. The catalytic activity of these materials was investigated in the photooxidation of amines to imines, showing the retention of the photocatalytic effectiveness of the parent pristine MOF.
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Mar 2025
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I15-1-X-ray Pair Distribution Function (XPDF)
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Shichun
Li
,
Chao
Ma
,
Jingwei
Hou
,
Shuwen
Yu
,
Aibing
Chen
,
Juan
Du
,
Philip A.
Chater
,
Dean S.
Keeble
,
Zhihua
Qiao
,
Chongli
Zhong
,
David A.
Keen
,
Yu
Liu
,
Thomas D.
Bennett
Diamond Proposal Number(s):
[20038]
Open Access
Abstract: Crystalline metal-organic frameworks (MOFs) exhibit enormous potential application in gas separation, thanks to their highly porous structures and precise pore size distributions. Nevertheless, the inherent limitations in mechanical stability of crystalline MOFs cause challenges in processing MOF powders into bulky structures, particularly for membrane filtrations. Melt-quenched MOF glasses boast excellent processability due to liquid-like properties. However, the melting process diminishes the inherent porosity, leading to reduced gas adsorption capacities and lower gas diffusion coefficients. In this work, we demonstrated that enhancing the porosity of MOF glasses is achievable through topological engineering on the crystalline precursors. Crystalline zeolitic imidazolate frameworks (ZIFs) with large 12-membered rings pores, including AFI and CAN topology, were synthesized by using both structure-directing agents and mixed organic ligands. The large pores are partially preserved in the melt-quenched glass as evidenced by high-pressure CO2 absorption at 3000 kPa. The agAFI-[Zn(Im)1.68(bIm)0.32] glass was then fabricated into self-supported membranes, which shows high gas separation performance, for example, CO2 permeance of 3.7 × 104 GPU with a CO2/N2 selectivity of 14.8.
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Feb 2025
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I09-Surface and Interface Structural Analysis
I15-1-X-ray Pair Distribution Function (XPDF)
I21-Resonant Inelastic X-ray Scattering (RIXS)
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Liquan
Pi
,
Erik
Bjorklund
,
Gregory J.
Rees
,
Weixin
Song
,
Chen
Gong
,
John-Joseph
Marie
,
Xiangwen
Gao
,
Shengda D.
Pu
,
Mikkel
Juelsholt
,
Philip A.
Chater
,
Joohyuk
Park
,
Min Gyu
Kim
,
Jaewon
Choi
,
Stefano
Agrestini
,
Mirian
Garcia-Fernandez
,
Ke-Jin
Zhou
,
Alex W.
Robertson
,
Robert S.
Weatherup
,
Robert A.
House
,
Peter G.
Bruce
Diamond Proposal Number(s):
[27336, 29028, 25807]
Abstract: Disordered rocksalt cathodes deliver high energy densities, but they suffer from pronounced capacity and voltage fade on cycling. Here, we investigate fade using two disordered rocksalt lithium manganese oxyfluorides: Li3Mn2O3F2 (Li1.2Mn0.8O1.2F0.8), which stores charge by Mn2+/Mn4+ redox, and Li2MnO2F, where charge storage involves both Mn3+/Mn4+ and oxygen redox (O-redox). Li3Mn2O3F2 is reported for the first time. We identify the growth of an electronically resistive surface layer with cycling that is present in both Li2MnO2F and Li3Mn2O3F2 but more pronounced in the presence of O-redox. This resistive surface inhibits electronic contact between particles, leading to the observed voltage polarization and capacity loss. By increasing carbon loading in the composite cathode, it is possible to substantially improve the cycling performance. These results help to disentangle O-redox from other leading causes of capacity fading in Mn oxyfluorides and highlight the importance of maintaining electronic conductivity in improving capacity and voltage retention.
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Dec 2024
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