B18-Core EXAFS
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Abstract: Polychlorinated aromatic hydrocarbons (PCAHs) in flue gas seriously threaten the environment and human health, and Ru-based catalysts exhibit efficient oxidation property for PCAHs removal. However, the current Ru catalysts either have high Ru loading/non-stable structure or are developed empirically whilst lack of design mechanism. Herein, a robust Ru single atom catalyst (0.5 Ru1/TiO2) was designed based on metal-support interaction for o-DCB (o-dichlorobenzene, a typical PCAHs) degradation, and it revealed significantly better oxidation activity with T50 = 207.4 °C and T90 = 243.5 °C than its contrast with weak metal-support interaction (0.5 RuNP/TiO2, T50 = 247.4 °C, T90 > 300 °C). In addition, 0.5 Ru1/TiO2 exhibited much better chlorine resistance stability, maintaining >90% o-DCB conversion for 700 min versus∼70% on 0.5 RuNP/TiO2. The superior performance of 0.5 Ru1/TiO2 was attributed to its stronger metal-support interaction between Ru and TiO2, verified by H2-TPR, which offered higher active oxygen species (22.4%), more Lewis acid (0.675 mmol/g) and higher exposed Ru ratio (> 90.0%) than 0.5 RuNP/TiO2 (15.0%, 0.068 mmol/g, 28.6%, respectively). The above properties can not only enhance o-DCB adsorption/activation and weaken its Csingle bondCl bonds but also favor partial/deep oxidation and remove deposited chlorine on 0.5 Ru1/TiO2, proved by in situ FT-IR. Moreover, notable higher water resistance under different water vapor and applicability under varied pollutant concentration were observed on the robust Ru1/TiO2. This work reveals insightful function-property study on Ru single atom catalysts for PCAHs oxidative removal.
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May 2026
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B07-B1-Versatile Soft X-ray beamline: High Throughput ES1
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Diamond Proposal Number(s):
[40403]
Open Access
Abstract: γ-Valerolactone (GVL) is a valuable bio-based chemical, solvent and fuel additive derived from levulinic acid, a key platform chemical from lignocellulosic biomass. Catalytic transfer hydrogenation (CTH) of levulinic acid using secondary alcohols as hydrogen donors presents a sustainable alternative to conventional hydrogenation with molecular hydrogen and can be efficiently carried out with inexpensive oxides. Here, we demonstrate how controlled silica incorporation onto zirconia provides a route to tailor acidity and thus direct reactivity in the CTH of levulinic acid and its esters to GVL. Silica-doped zirconia catalysts with varying Si loadings were synthesised via colloidal deposition and comprehensively characterised using ICP-OES, TEM/EDX, XRD, BET, NH3-TPD, pyridine-adsorbed DRIFTS, XPS and NEXAFS. Moderate silica incorporation enhanced surface area, stabilised the tetragonal ZrO2 phase, and increased total acidity, and most importantly, altered the Brønsted-to-Lewis acid balance that dictated the reactivity. Ethyl levulinate conversion was favoured over Lewis acid-rich catalysts, whereas LA conversion required higher Brønsted acidity. The optimal catalyst (6 wt% Si) delivered 80% GVL yield from levulinic acid at 190 °C in 4 hours. Isopropyl levulinate was identified as a side-product that can also convert to GVL via CTH, though less efficiently. The 6 wt% Si/ZrO2 catalyst exhibited excellent stability across three consecutive cycles without calcination, demonstrating resistance to leaching, a major drawback of heterogeneous catalysts in liquid-phase reactions, as well as to carbon deposition. This study demonstrates that silica doping provides an effective means of tuning zirconia acidity, resulting in catalysts that combine good stability with practical applicability in sustainable chemistry.
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Jan 2026
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I19-Small Molecule Single Crystal Diffraction
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Diamond Proposal Number(s):
[30280]
Open Access
Abstract: Crystalline solvates, including hydrates, hold untapped potential in pharmaceutical development, yet their exploitation remains minimal due to the difficult and laborious task of unequivocally establishing their physical stabilities. We introduce Controlled Solvent-Activity Liquid-Assisted Grinding (CSA-LAG), a mechanochemical protocol that offers solvate phase boundary elucidation by varying the activity of a chosen solvent in defined binary/ternary mixtures and analysing the equilibrated resulting solid form. Using small API amounts, CSA-LAG reaches equilibrium within minutes and yields critical solvent activities that delimit neat, hydrated, solvated and competing-solvate domains. The method uses mixtures of known thermodynamic activities, requires far less material and time than traditional slurries and affords high reproducibility. Applied to four pharmaceutical compounds, CSA-LAG reproduces slurry boundaries and quantifies activity thresholds for single, stepwise and competitive solvations. Defining these boundaries enables rational form selection and process design either by avoiding or targeting solvates, whilst turning a month-scale empirical screening into a rapid, thermodynamically guided workflow.
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Jan 2026
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I04-Macromolecular Crystallography
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Ella K.
Reid
,
Connor G.
Miles
,
Henry O.
Lloyd-Laney
,
Alison K.
Nairn
,
Jessie
Branch
,
Nicholas
Garland
,
Nicholas D. J.
Yates
,
Alex
Ascham
,
Paul H.
Walton
,
Glyn R.
Hemsworth
,
Alison
Parkin
Diamond Proposal Number(s):
[19248]
Open Access
Abstract: Lytic polysaccharide monooxygenases ([L]PMOs) are copper-containing enzymes that catalyse cleavage of the glycosidic bond, a process central to microbial biomass degradation. Here, we describe electrochemical methods used to investigate the Cu2+/1+ redox chemistry and the polysaccharide-free catalytic activity of two AA10 LPMOs: CjAA10B from Cellvibrio japonicus and CfAA10 from Cellulomonas fimi. Immobilisation of these enzymes on the surface of a graphite electrode allows for direct electrochemical measurements of Cu2+/1+ redox cycling as well as the ability of both LPMOs to reduce H2O2 vs O2. These measurements can be advantageous when compared to biological dye assays as they provide direct kinetic measurements and allow for investigation over a wider range of environmental conditions. Values of kcat and KM- are reported for H2O2 and O2 reduction by CjAA10B and CfAA10 from pH 5–7, with CfAA10 consistently outperforming CjAA10B. Both enzymes perform faster catalysis with H2O2 but when comparing the affinity-coupled specificity constant (kcat/KM), the LPMOs perform similarly with both H2O2 and O2, suggesting both substrates are viable. We also note an increase in redox signals as pH is decreased that correlates with EPR data suggesting a second species is formed <pH 5, postulated to occur due to the protonation of a glutamate residue (pKa ∼ 4.6). The increase in signal size with decreasing pH that is seen for the non-catalytic Cu2+/1+ transition is interpreted in light of an increasing proportion of electroactive species at low pH; such a change in activity with pH is notably not observed in the presence of substrate (H2O2 or O2). This suggests that substrate binding modulates the active site, disrupting the effect of protonation. These findings establish electrochemistry as a powerful tool for probing LPMO activity.
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Jan 2026
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I04-Macromolecular Crystallography
I24-Microfocus Macromolecular Crystallography
VMXm-Versatile Macromolecular Crystallography microfocus
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Open Access
Abstract: Structure determination by X-ray diffraction is limited by crystal size and can be compromised by radiation damage when using very intense X-ray radiation. X-ray structure determination from partial diffraction data sets combined from multiple crystals is a potential solution, but its exploitation in chemistry and materials science is largely unrealized. Here we report the use of synchrotron radiation for multi-crystal X-ray diffraction (MCXRD) adapted for structure determination of metal-organic framework (MOF) materials with crystal dimensions too small for conventional single-crystal diffraction studies. We further show that radiation-induced chemical changes and degradation of diffraction quality can be alleviated. Our approach encompasses both rotation- and stationary-MCXRD measurements for 10 to 1000s of crystals with software-optimized combination of the multiple data sets. We report the crystal structures of six MOFs: MOF-919(Sc/Cu), MET-2, MIL-88B(Cr)-1,4-NDC, PCN-260(Sc), UiO-66, and UiO-66-MoO4 with unit cell dimensions ranging from 18−114 Å and crystal sizes from 0.5−480 µm3. This approach can address the challenges of structure determination in a regime of particle size and sample radiation sensitivity that lies between existing single-crystal X-ray diffraction and the emerging field of electron diffraction. MCXRD can provide accurate atomic-resolution structure determination for some of the most challenging cases in chemistry and materials science.
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Jan 2026
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I15-Extreme Conditions
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Vasiliki
Faka
,
Mohammed
Alabdali
,
Martin A.
Lange
,
Franco M.
Zanotto
,
Can
Yildirim
,
Mikael Dahl
Kanedal
,
Jędrzej
Kondek
,
Matthias
Hartmann
,
Oliver
Maus
,
Dominik
Daisenberger
,
Michael Ryan
Hansen
,
Jozef
Keckes
,
Daniel
Rettenwander
,
Alejandro
Franco
,
Wolfgang G.
Zeier
Diamond Proposal Number(s):
[36607]
Open Access
Abstract: Solid-state battery fabrication requires the densification of solid electrolytes to achieve optimal cycling performance and high energy density. However, the underlying compaction mechanisms of these electrolytes remain poorly understood. Here, we investigate the effect of pressure consolidation on the ionic conductor Li6PS5Cl with particle size distributions (PSD) ranging from 4 to 40 µm. Heckel analysis reveals that samples with smaller PSDs exhibit higher compressibility at lower pressures. X-ray diffraction peak profiling shows that applied pressure induces lattice strain, leading to peak broadening, while pair distribution function analysis demonstrates a reduction in coherence length upon pressing. Dark-field X-ray microscopy further provides spatially resolved orientation maps, uncovering intragranular structural variations within individual Li6PS5Cl agglomerates after compression. To better understand the origin of stress fluctuations, we performed discrete element method simulations using the experimental PSDs. The results indicate that smaller particles and broader PSDs experience higher stresses, whereas monodisperse systems do not exhibit significant stress fluctuations with position or particle size. This suggests that the high strain observed cannot be attributed solely to smaller particles, but rather to size inhomogeneity. Overall, these findings highlight that both particle size and its distribution play a critical role in processing solid electrolytes for solid-state batteries.
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Jan 2026
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E01-JEM ARM 200CF
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Naomi
Lawes
,
Igor
Kowalec
,
Sofia
Mediavilla-Madrigal
,
Kieran J.
Aggett
,
Louise R.
Smith
,
Malcolm
Dearg
,
Thomas J. A.
Slater
,
Eimear
Mccarthy
,
Herzain I.
Rivera-Arrieta
,
Matthias
Scheffler
,
David J.
Morgan
,
David J.
Willock
,
Andrew M.
Beale
,
Andrew J.
Logsdail
,
Nicholas F.
Dummer
,
Michael
Bowker
,
C. Richard A.
Catlow
,
Stuart H.
Taylor
,
Graham J.
Hutchings
Diamond Proposal Number(s):
[3104]
Open Access
Abstract: A series of PdZn/TiO2 catalysts prepared by chemical vapor impregnation (CVI) were tested for CO2 hydrogenation at 20 bar pressure and at temperatures of 230–270 °C. Changing the Pd and Zn molar ratio (Zn:Pd = 0–20) in a PdZn/TiO2 catalyst has a dramatic effect on selectivity for the CO2 hydrogenation reaction. Pd alone shows three main products: methanol, CO, and methane. Addition of small quantities of Zn results in the formation of a PdZn alloy, preventing methanation. At equimolar ratios of Pd and Zn, a 1:1 β-PdZn alloy is formed and a reverse water gas shift catalyst is produced. Adding Zn in excess relative to the Pd loading results in the formation of ZnO on the TiO2 surface in addition to the PdZn alloy, dramatically increasing methanol selectivity from 5% at Zn:Pd = 1 to 55% for Zn:Pd = 2. Through a combination of theory and experiment, the active site for methanol synthesis is concluded to be the interface between PdZn nanoparticles and the ZnO overlayer on the TiO2, where interfacial formate can react with hydrogen dissociated by the metal nanoparticle.
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Jan 2026
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I13-2-Diamond Manchester Imaging
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Diamond Proposal Number(s):
[33261]
Open Access
Abstract: Lithium metal (LM) and zero-excess lithium (ZE) anodes offer pathways to increase the energy density of all-solid-state batteries (ASSBs). We employ operando X-ray computed tomography combined with an image subtraction method to visualize lithium plating/stripping morphology, stack mechanical failure, and quantify the lithium reversibility in asymmetric Li6PS5Cl (LPSC)-based ASSBs. Lithium metal counter electrode (CE) and copper (Cu) working electrode (WE) emulate LM and ZE interface configurations, respectively. We compare bare Cu and silver-coated Cu (Ag/Cu) WEs under varying current densities. At 0.25 mA cm−2(WE), bare Cu shows edge-localized and non-uniform lithium deposition, while Ag/Cu facilitates more uniform lithium spreading, but results in higher first-cycle irreversibility and lower Coulombic efficiency. Above 0.5 mA cm−2(WE), failure in Li|LPSC|Cu cells initiate at the LPSC|Cu interface via spallation cracks. In contrast, Ag preserves interface integrity at the WE despite lithium initially plates at discrete nucleation spots. However, failure shifts to the Li|LPSC interface, where non-uniform lithium depletion at the CE exposes the underlying Cu, leading to spallation cracks upon subsequent plating. Mechanical finite element simulations support these observations and underscore the critical role of the nucleation layers in mitigating mechanical failure. This study highlights interface engineering as a key strategy to address electro-chemo-mechanical degradation in LM- and ZE-ASSBs.
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Jan 2026
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B18-Core EXAFS
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Diamond Proposal Number(s):
[34632]
Open Access
Abstract: Mitigating carbon emissions and plastic waste is a pressing societal challenge due to the disruptive environmental impact of incremental accumulation. A promising strategy to address both issues is coelectrolysis of CO2 and PET-plastic waste to high-value commodity chemicals. Here, we report electrocatalytic upcycling of polyethylene terephthalate (PET) plastic to formate and terephthalic acid using a cobalt-based metal–organic framework (Co-MOF-74). The electrocatalyst underwent oxidative restructuring to cobalt oxyhydroxide under operating conditions and exhibited near-unity faradaic efficiency (FE) for the ethylene glycol oxidation reaction (EGOR) to formate during short-term electrolysis. Notably, EGOR required 0.23 V lower potential compared to the conventional oxygen evolution reaction (OER) at a current density of 100 mA cm–2. When coupled with a CO2 reducing cathode, a maximum combined FE of 156% was achieved for formate (anode) and syngas (cathode) at a cell voltage (Ecell) of 1.6 V. Upon integration of the EGOR electrode in a CO2-fed flow cell, the coupled system required an Ecell of ∼2.3 V to operate at 75 mA cm–2. This work presents a promising integrated approach that offers a compelling solution for mitigating environmental pollution by enabling the electrochemical reforming of CO2 and plastic waste into valuable chemicals under cost-effective and energy-efficient conditions.
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Jan 2026
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I11-High Resolution Powder Diffraction
I15-1-X-ray Pair Distribution Function (XPDF)
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Diamond Proposal Number(s):
[32893, 39378]
Open Access
Abstract: Sr2MnO2Cu3.5S3 contains mixed-valent Mn ions Mn2+/3+ in axially elongated MnO4S2 octahedra connected via apical sulfide anions to copper-deficient antifluorite-type Cu4-δS3 layers where δ ∼ 0.5. Copper deficiency is charge-compensated by oxidation of Mn 3d states resulting in mixed-valency. The compound is tetragonal in P4/mmm at ambient temperatures (a = 4.016345(1) Å, c = 11.40708(5) Å). Below 190 K, superlattice reflections in diffraction data and an increase in resistivity, signal checkerboard charge-ordering of Mn2+ and Mn3+. The superstructure approximates to a √2a × √2a × 2c expansion of the room temperature cell in space group P42/nmc. However, satellite reflections signal a (3 + 2)D incommensurate modulation of Cu site occupancies in the Cu-deficient sulfide layers coupled with displacements of the sulfur positions; overall the superstructure below 190 K requires description in superspace group P42/nmc(a,0,0)0000(0,a,0)00s0. Analysis of total scattering measurements along with pair distribution functions supports the charge-ordered low temperature model and reveals local order of distinct Mn sites within the higher-temperature charge-disordered regime. Below TN = 27 K, long-range magnetic ordering is A-type antiferromagnetic with distinct moments for Mn2+ and Mn3+ ions directed perpendicular to the MnO2 planes and ordered ferromagnetically. Long-range antiferromagnetic order results from interlayer antiferromagnetic coupling. A metamagnetic transition at 1.1 T corresponds to a change to long-range interlayer ferromagnetic ordering via a spin-reorientation of magnetic moments and is associated with a slight decrease in the charge separation between the Mn sublattices, consistent with observations on mixed-valent perovskite and Ruddlesden–Popper-type oxide manganites.
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Jan 2026
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