I11-High Resolution Powder Diffraction
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Diamond Proposal Number(s):
[33667]
Open Access
Abstract: The use of conventional zirconium alloys at temperatures above 400 °C is limited by high temperature strength and creep resistance. This has prevented the consideration of zirconium alloys for fusion and Generation IV fission plant designs operating at 500 °C–1000 °C. The physical metallurgy of zirconium is similar to titanium which has seen alloying advances allowing application temperatures up to 600 °C. Although the oxidation resistance of zirconium-based alloys is expected to be poor, in a water environment, new Generation-IV and fusion reactors are designed to operate using alternative coolants such as liquid metals and molten salts. Therefore, a new class of zirconium alloys in the Zr-Al-Sn-(Si,Cr,V) system, designed by analogy to near-
titanium alloys, were synthesised by arc melting and processed in a sequence of homogenisation, hot/cold rolling, recrystallisation, and ageing treatments. Microscopy and diffraction identified a refined fully lath grain structure reinforced by nanoscale lamellar or discrete coherent Zr3Al precipitates, with morphology and crystal structure differing with ageing times. Additionally alloying with Si, Cr, and V respectively leads to Zr2Si, ZrCr2, and ZrV2 incoherent precipitates. Tensile testing revealed a strengthening effect by Al, but with significant changes to ductility on ageing depending on the evolution of Zr3Al. Creep testing showed creep rates orders of magnitude better than conventional Zircaloy-4 and nuclear ferritic/martensitic steels, approaching near-
Ti alloys. The present work offers new insights and perspectives into how high-temperature zirconium alloys might be designed to meet the requirements for fusion and Gen-IV fission.
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Mar 2026
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I11-High Resolution Powder Diffraction
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Ziqin
Jiao
,
Tao
Zeng
,
Wenhai
Ji
,
Zheng
Liu
,
Wenguang
Zhao
,
Xiaoyu
Gao
,
Yongbiao
Mu
,
Xuansi
Jiang
,
Yubin
Li
,
Guojie
Chen
,
Wenqing
Yao
,
Jinqi
Li
,
Ze
He
,
Juping
Xu
,
Ping
Miao
,
Wen
Yin
,
Yuguang
Pu
,
Rui
Wang
,
Yinguo
Xiao
Diamond Proposal Number(s):
[34243]
Abstract: Lattice-oxygen redox (L-OR) has been widely considered a viable approach to attain high-capacity cathodes for next-generation batteries. However, achieving highly reversible L - OR remains challenging due to the intrinsic chemical instability of lattice oxygen. As such, stabilizing the lattice oxygen becomes necessary for improving the performance of cathode materials with oxygen redox chemistry. In this study, the distinct properties of both bulk and surface lattice oxygen are systematically studied in a model Li-rich layered oxide material (LRMO, i.e., Li1.2Ni0.2Mn0.6O2) by employing different techniques. We find that, in the bulk, distortions in octahedral coordination geometry are closely correlated with variations in the electronic structure, and the substitution of Li ions with protons in a subsurface layer enhances the stability of surface lattice oxygen by altering its coordination environment. By jointly regulating the local environments of both bulk and surface lattice oxygen, the initial Coulombic efficiency is remarkably improved from 73.88% to 91.72%. Moreover, the modified LRMO demonstrates an impressive cycle stability, which realizes a capacity retention of 95.9% after 500 cycles at 250 mA g−1. This work demonstrates that rationally-designed local environments of lattice oxygen can effectively stabilize the oxygen redox in Li-rich cathodes.
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Feb 2026
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B18-Core EXAFS
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Fei
Guo
,
Manxi
Gong
,
Longxiang
Liu
,
Bochen
Li
,
Ruwei
Chen
,
Mengjun
Gong
,
Wei
Zong
,
Jianuo
Chen
,
Qi
Li
,
Jing
Li
,
Yunpeng
Zhong
,
Zeyi
Zhang
,
Jianrui
Feng
,
Rhodri
Jervis
,
Guanjie
He
Diamond Proposal Number(s):
[34632]
Open Access
Abstract: Platinum–transition metal (PtM) alloys are among the most promising oxygen reduction reaction (ORR) catalysts, yet their practical deployment in proton-exchange membrane fuel cells (PEMFCs) is hindered by transition-metal dissolution, particle coarsening, and insufficient durability. Moreover, conventional alloying or intermetallic ordering strategies often aggravate these issues by inducing severe nanoparticle aggregation and instability. Here we report a controllable alloying–dealloying strategy to construct PtNi nanoparticles confined in an N-doped carbon framework (Pt1Ni1-x@Nix_NC). Ammonia-assisted dealloying produces a Pt-rich shell with an alloyed core, while the N-doped carbon anchors the released Ni atoms form Ni–N/C moieties, thereby suppressing agglomeration and strengthening metal–support interactions. This coordination–support coupling optimizes Pt 5d orbital occupation, weakens oxygen adsorption, and accelerates ORR kinetics. Consequently, Pt1Ni1-x@Nix_NC exhibits a half-wave potential of 0.932 V and an ultrahigh mass activity of 2.028 A mgPt−1, which is 8.75-fold higher than commercial Pt/C and among the best values reported to date for PtNi-based catalysts. Remarkably, it shows only a 6 mV half-wave potential loss after 30,000 cycles, demonstrating exceptional durability. In PEMFCs, the fuel cell delivers 975 mW cm−2 peak power density and retains 91.9% of initial performance, underscoring a generalizable approach for designing durable, high-performance low-PGM catalysts for next generation PEMFCs.
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Feb 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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I12-JEEP: Joint Engineering, Environmental and Processing
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Sam
Riley
,
Antonios
Vamvakeros
,
Gustavo
Quino
,
John
Morley
,
Mengzheng
Ouyang
,
Andrew
Shevchuk
,
Kehan
Huang
,
Pierre-Olivier
Autran
,
Stefan
Michalik
,
Genoveva
Burca
,
Billy
Wu
,
Nigel
Brandon
,
Chandramohan
George
Diamond Proposal Number(s):
[36699]
Open Access
Abstract: Understanding the strain tolerance of both standard and mechanically flexible battery electrodes is prerequisite for optimizing performance, safety, and longevity, particularly in heavy-duty applications, flexible electronics and wearables. Achieving this requires a deeper understanding of how mechanical strain drives electrode degradation. In this work, we directly compare the strain response of electrospun (flexible) and slurry-cast (conventional) electrodes. To simulate acute mechanical stress, electrodes underwent a controlled 180° folding, pressing, and unfolding protocol designed to induce measurable damage, we then employed a combination of characterization techniques, including synchrotron X-ray nano-computed tomography, X-ray diffraction mapping, electrochemical analysis, and in situ Tensiometer-scanning electron microscopy to assess both structural and electrochemical degradation modes and provide a standardised upper-bound for strain induced damage. Our results reveal that electrospun electrodes exhibit significantly greater resilience to deformation, attributed to their freestanding architecture and fibrous morphology. These findings underscore the importance of characterizing deformation mechanisms to guide the design of high-performance batteries.
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Jan 2026
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I19-Small Molecule Single Crystal Diffraction
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Diamond Proposal Number(s):
[40576]
Open Access
Abstract: Photocatalysis offers a promising approach for renewable energy conversion and storage, but short lifetimes of charge-separated states in photocatalysts due to charge recombination limit its utility. Here we report an organic molecule with an acceptor–donor–acceptor configuration that can self assemble into highly crystalline nanoparticles. Transient absorption spectroscopy reveals that these crystalline assemblies can induce an ultra-long-lived charge-separated state of up to 1.2 s, attributed to initial symmetry-breaking charge separation, followed by charge hopping across closely packed molecules. These self-assembled nanoparticles have an impressive photocatalytic H2 evolution rate of 126 mmol g−1 h−1 with an external quantum efficiency of 12% at 550 nm under optimized conditions. This system shows a remarkable stability with 220 million turnover numbers (per particle) over the 77 h of operation. These findings suggest that rational design of organic molecules and their aggregates is vital for improving light-induced charge separation and for developing highly efficient, stable and scalable organic photocatalysts.
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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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B18-Core EXAFS
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Abstract: The large-scale deployment of proton exchange membrane water electrolyzers (PEMWEs) is hindered by the scarcity and instability of iridium-based oxides (IrOx) catalysts during the acidic oxygen evolution reaction. Herein, we report a dynamic embedding strategy to construct highly stable and active low-iridium catalysts, which enables controlled incorporation of IrOx nanoclusters (NCs) into an amorphous TiOx overcoating supported on carbon nanotubes (IrOx/TiOx@CNT). Combined experimental and theoretical studies reveal that the dynamic embedding process enables coordinated growth kinetics, facilitating continuous anchoring of IrOx NCs within the flexible amorphous TiOx matrix. The resulting strong IrOx-TiOx interaction promotes significant electron transfer from TiOx to IrOx, thereby optimizing the adsorption energetics of oxygen intermediates and suppressing IrOx dissolution. The optimized catalyst achieves an exceptionally low overpotential of 258 mV at 10 mA cm−2 and outstanding durability in 0.5 m H2SO4. In PEMWE, the catalyst enables a cell voltage of 1.70 V at 1.0 A cm−2 with an ultralow Ir loading (0.3 mg cm−2), coupled with low energy consumption (45 kWh kg−1 H2) and hydrogen production cost (∼$0.9 kg−1 H2). This work underscores the pivotal role of amorphous overlayers in creating dynamically stable interfaces for advanced electrocatalysis.
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Jan 2026
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I11-High Resolution Powder Diffraction
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Diamond Proposal Number(s):
[36397]
Open Access
Abstract: Although it is widely accepted that the long-range (average) crystal structure plays a critical role in determining the electrochemical performance of battery materials, the relationship between local structural features and electrochemical performance is rarely studied. Disordered rock salt oxides (DRX), which have become serious contenders for next generation Li-ion electrode materials, provide an ideal platform for exploring correlations between local structure and electrochemical performance as they exhibit a simple face-centered cubic structure and combine long-range disorder and short-range order on the cation sublattice. This work examines the Li1.1Mn0.7Zr0.2−xTixO2 series of DRX cathodes and investigates the links between local structure rearrangements and capacity activation. The end-member Li1.1Mn0.7Zr0.2O2 compound exhibits a low capacity in the as-synthesized state, attributed to unfavorable short-range order that hinders Li-ion transport, yet its capacity increases seven-fold, from 20 to 140 mAh g−1, after chemical delithiation followed by a 400 °C heat treatment. Capacity activation is associated with the appearance of local spinel-like structural features that depart from the short-range order originally present in the material, without significant change to the bulk composition and average crystal structure. Investigation of a series of Li1.1Mn0.7Zr0.2−xTixO2 (x ≤ 0.2) DRX compounds reveals that the correlation length of the spinel-like ordering that emerges during the heat treatment strongly depends on the Zr[thin space (1/6-em)]:[thin space (1/6-em)]Ti ratio. Yet, dramatic capacity activation and electrochemical (pseudo-)plateaus reminiscent of Mn-based spinel cathodes are observed for all compounds irrespective of the size of the ordered domains. To explain this phenomenon, we propose that the DRX phase undergoes a complete transformation to a spinel-like domain structure, which improves bulk Li-ion transport regardless of domain size.
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Jan 2026
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Daniel J.
Zheng
,
Kaylee
Mccormack
,
Jiayu
Peng
,
Raul
Garcia-Diez
,
Elmar Yu
Kataev
,
Fabian
Schwarz
,
Susan
Nehzati
,
Jakob
Thyr
,
Wilson
Quevedo-Garzon
,
Benjamin
Howchen
,
Marcus
Bär
,
Yuriy
Román-Leshkov
,
Yang
Shao-Horn
,
Mikaela
Görlin
Abstract: The oxygen evolution reaction (OER) is crucial for electrofuel production. Metal–hydroxide organic frameworks (MHOFs), a subset of metal–organic frameworks with oxyhydroxide-like layers interconnected via organic linkers, have shown great promise as OER electrocatalysts. This study investigates lattice oxygen exchange in four Ni- and Fe-substituted MHOFs with varying linker stabilities using 18O isotope labeling combined with operando Raman spectroscopy. A negative correlation between 18O/16O lattice oxygen exchange and the OER activity is shown, with Fe ions further suppressing exchange. Operando X-ray spectroscopy (XAS) and UV–vis further reveals that lattice oxygen exchange primarily proceeds on reduced Ni2+ sites, with higher linker stability preserving more Ni2+ sites and promoting greater lattice oxygen exchange. Supported by density functional theory, the MHOF surface transforms into an OER-active MOxHy-like phase, explaining the negative correlation of lattice exchange with the OER activity. This work also identifies a noninnocent role of the Raman laser in inducing lattice oxygen exchange and offers critical insights into various lattice oxygen exchange pathways in MHOFs, demonstrating their distinction from the catalytic lattice oxygen evolution reaction mechanism.
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Dec 2025
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