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Abstract: This work evaluates the feasibility of an X-ray-voltaic element based on a CH3NH3PbI3 perovskite single crystal, which combines excellent scintillation and photovoltaic properties. It was demonstrated that the X-ray-voltaic effect in this material can only be achieved if the sample is transformed from its initial antiferroelectric state to a ferroelectric state through exposure to intense UV light. The observed generation of free current carriers is explained by a combination of two effects─the direct X-ray-to-current conversion and the conventional PV effect generated due to excitonic X-ray luminescence. The crucial role of the second mechanism is confirmed by the observed temperature changes in the photocurrent density, which was found to be proportional to the intensity of the excitonic luminescence band. It was also shown that ionic conductivity arising in the sample mostly under the influence of light photons partially compensates the flow of the free electrons and holes generated due to the conventional PV and X-ray-voltaic effects. Although the value of the generated power at room temperature in the proposed device was found to be considerably lower in comparison with those for the best X-ray-voltaic batteries based on the semiconductor p-n-junctions, it has been shown that its photoresponse increases 2 orders of magnitude at low temperatures. Besides, the technology of its manufacturing is considerably simpler and cheaper. Moreover, the significant increase in the photocurrent at cryogenic temperatures offers a crucial advantage when the proposed power cell is applied in outer space.
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Oct 2025
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I14-Hard X-ray Nanoprobe
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Diamond Proposal Number(s):
[34794]
Abstract: Nanoscale molecular interactions between growing crystals and charged polyelectrolytes are crucial to understand the self-assembly of hierarchical organic–inorganic superstructures. Little is known about earth alkaline sulfate biominerals. Yet, a detailed understanding of bioinspired crystallization is crucial for developing general descriptors for bottom-up syntheses of complex ceramics. This study investigates biomimetic strontium sulfate (SrSO4) crystallization in the presence of poly(α-glutamic acid) using multiscale microscopy and vibrational spectroscopy. Using scanning electron microscopy, we observed doughnut-shaped spherulites with granular surface texture. Biomolecule inclusion led to pronounced peak broadening in synchrotron X-ray powder diffraction, wide-angle X-ray scattering, and Raman spectroscopy, commensurate with nanoscale domain sizes and pronounced lattice strain. Texture-like wide-angle X-ray scattering patterns and nanosized domains in transmission electron microscopy support the notion of mesocrystalline organization. Based on Z-contrast STEM imaging, intercalated organics are organized as elongated nanoclusters. Diffracting planes radiate outward from the crystal center, indicating a centrosymmetric strain field. The three-dimensional (3D) chemistry was investigated using atom probe tomography, which revealed a helical distribution of organic inclusions. This approach exemplifies how organic–inorganic templating can guide the evolution of intricate biomorphic crystal shapes. Round strontium sulfate crystals bear technological potential in the field of optoelectronics, such as IR–vis conversion materials or curved waveguides.
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Oct 2025
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I11-High Resolution Powder Diffraction
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Lutong
Shan
,
Tianxiang
Chen
,
Shiyun
Li
,
Boya
Tang
,
Yuhang
Yang
,
Peng
Rao
,
Jiangnan
Li
,
Ching Kit Tommy
Wun
,
Daniel
Lee
,
Mufan
Li
,
Tsz Woon Benedict
Lo
,
Sihai
Yang
Diamond Proposal Number(s):
[37887]
Abstract: The concerted electron–proton transfer (CEPT) can substantially enhance the microkinetics of electrocatalysis by circumventing the formation of high-energy intermediates. Herein, we report the decoration of the MFI zeolite matrix with isolated Cu(II) sites in the proximity of intrinsic Brønsted acid sites (BASs), promoting the CEPT synergy in electrocatalysis. By modulating the spatial arrangement of “Cu-BAS” pairs in Cu-Z(23) zeolite, we show a Faradaic efficiency of 98% for electroreduction of nitrate to ammonia, achieving an exceptional yield of 103.1 mg h–1 cm–2 at a current density of 1.3 A cm–2. Cu-Z(23) also exhibits an excellent activity at low concentrations of nitrate (e.g., 50 ppm) and a high catalytic stability of 50 h. Synchrotron X-ray powder diffraction, solid-state nuclear magnetic resonance spectroscopy, and modeling studies reveal the critical role of the proximate “Cu-BAS” pairs in facilitating the CEPT process. This approach uncovers the overlooked capability of “electrical insulating” zeolites as effective electrocatalysts to drive future sustainable chemical synthesis.
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Sep 2025
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I22-Small angle scattering & Diffraction
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Diamond Proposal Number(s):
[35286]
Open Access
Abstract: Benzophenone-based materials remain widely used as photoinitiators for ultraviolet light-induced free radical polymerizations. Traditionally, polymerization is spatially controlled using top-down techniques such as photomasks, which produce well-defined polymeric films. In contrast, we present an alternative method for controlling polymerization by employing supramolecular materials to localize the photoinitiator. This approach uses benzophenone-functionalized dipeptides that are specifically tuned to enable supramolecular gel noodle formation, which act as structural templates. We show that polymerization of acrylate monomers around the gel noodles can increase the Young’s modulus by up to 2 orders of magnitude and produce mechanically robust structures that can be handled. The self-assembly of the supramolecular photoinitiators is also explored using viscosity and SAXS measurements, providing an understanding of why only 4BPAcFF successfully forms gel noodles. Our method offers a simple yet effective technique for localizing polymerization, enabling fine-tuning of mechanical properties and the fabrication of intricate designs such as hollow-core structures.
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May 2025
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B21-High Throughput SAXS
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Jacek K.
Wychowaniec
,
Ezgi Irem
Bektas
,
Marcia
Muerner
,
Jiranuwat
Sapudom
,
Martin
Šrejber
,
Marielle
Airoldi
,
Roland
Schmidt
,
Andrea J.
Vernengo
,
Charlotte J. C.
Edwards-Gayle
,
Paul Sean
Tipay
,
Michal
Otyepka
,
Jeremy
Teo
,
David
Eglin
,
Matteo
D'Este
Diamond Proposal Number(s):
[29767]
Open Access
Abstract: Self-assembling peptides (SAPs) are fully defined nanobiomaterials offering unprecedented opportunities to control nanostructure and chemical attributes to investigate and manipulate cellular signals. To investigate the influence of chemical and morphological characteristics on inflammatory signaling in native immunity, we designed five β-sheet SAPs: EFEFKFEFK (EF8), YEFEFKFEFK (YEF8), EFEFKFEFKY (EF8Y), YEFEFKFEFKY (YEF8Y), and EYEFKFEFK (EYF8) (F: phenylalanine; E: glutamic acid; K: lysine, Y: tyrosine). The position of tyrosine in the peptide sequence dictated the self-assembly into nanostructures, with all SAPs self-assembling into thin constituent nanofibers with d ≈ 3.8 ± 0.4 nm, and sequences YEF8 and EF8 showing a propensity for associative bundling. These distinct SAPs induced contrasting inflammatory responses of monocytic model THP-1 cells-derived macrophages (MΦs). Presence of soluble EF8 nanofibers (at 2 mM) induced an anti-inflammatory response and polarization toward an M2 state, whereas YEF8 (at 2 mM) displayed a tendency for inducing a pro-inflammatory response and polarization toward an M1 state. EF8Y, YEF8Y, and EYF8 SAPs did not induce an inflammatory response in our models. These results were validated using peripheral blood mononuclear cells (PBMCs)-derived MΦs from human donors, confirming the critical role of EF8 and YEF8 SAPs as possible orchestrators of the repair of tissues or inducers of pro-inflammatory state, respectively. The same MΦs polarization responses from THP-1-derived MΦs cultured on 20 mM hydrogels were obtained. These findings will facilitate the utilization of this family of SAPs as immunomodulatory nanobiomaterials potentially changing the course of inflammation during the progression of various diseases.
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Apr 2025
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B22-Multimode InfraRed imaging And Microspectroscopy
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Open Access
Abstract: Low-friction lubricant formulations are urgently needed to improve the energy efficiency of machines. Here, we show that blending 1-dodecanol with a hydrocarbon oil improves lubrication in nonconformal sliding/rolling contacts by simultaneously increasing hydrodynamic film thickness and reducing viscous friction. This is due to pressure-induced polymorphic phase transformations in the 1-dodecanol molecules after they flow through the film-thickness-determining inlet and reach the load-supporting zone. At relatively low pressures, 1-dodecanol forms a lamellar hexagonal solid polymorph that gives durable superlubricity and then, at higher pressures, it forms an orthorhombic polymorph. Both polymorphs cause anomalously low friction when blended into various hydrocarbon base oils over a wide range of speed, pressure, and shear rate conditions representative of rolling bearing and gear contacts. By breaking the ubiquitous tradeoff between friction and film thickness and enabling superlubricity, these blends pave the way for considerable energy efficiency improvements in widespread lubricated contacts.
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Mar 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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B18-Core EXAFS
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Diamond Proposal Number(s):
[36367]
Abstract: Deuterated compounds have broad applications across various fields, with dehalogenative deuteration serving as an efficient method to obtain these molecules. However, the diverse electronic structures of active sites in the heterogeneous system and the limited recyclability in the homogeneous system significantly hinder the advancement of dehalogenative deuteration. In this study, we present a catalyst composed of copper single-atom sites anchored within an ordered mesoporous nitrogen-doped carbon matrix, synthesized via a mesopore confinement method. The Cu1/OMNC-1100 catalyst, characterized by Cu–N4 sites, demonstrates exceptional performance, high functional group tolerance, and remarkable durability in the deuteration of 2-bromo-6-methoxynaphthalene under relatively mild conditions (80 °C, 2 MPa of CO). Experimental results combined with X-ray absorption fine structure analysis reveal that Cu–N3 sites can be converted into more stable Cu–N4 counterparts at higher pyrolysis temperatures, resulting in enhanced catalytic activity. This work demonstrates a strategy for designing single-atom site catalysts with tunable coordination environments, providing a promising approach to improving catalytic performance in selective dehalogenative reactions under relatively mild conditions.
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Jan 2025
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B21-High Throughput SAXS
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Diamond Proposal Number(s):
[35585]
Open Access
Abstract: Short bioactive peptide sequences are of great interest in biomaterials development. We investigate the self-assembly of a lipopeptide containing both the highly cationic CSK4 toll-like receptor agonist hexapeptide sequence and RGDS integrin-binding motif, i.e., C16-CSK4RGDS, as well as the control containing a scrambled terminal sequence C16-CSK4GRDS. Both lipopeptides are found to form micelles, as revealed by small-angle X-ray scattering and cryogenic transmission electron microscopy, and modeled using atomistic molecular dynamics simulations. We carefully examined methods to probe the aggregation of the molecules, i.e. to obtain the critical micelle concentration (CMC). Fluorescent probe assays using 1-anilino-8-naphthalenesulfonate (ANS) reveal low CMC values, 1–2 μM, which contrast with consistent values more than 2 orders of magnitude larger obtained from surface tension and electrical conductivity as well as unexpected UV/vis absorption spectra discontinuities and fluoresccence probe assays using Nile red. The anomalous results obtained from an ANS fluorescence probe are ascribed to the effect of ANS binding to the cationic (lysine and arginine) residues in the lipopeptide, which leads to a conformational change, as shown by circular dichroism, even at low concentrations below the actual CMC. Despite the small change in the peptide sequence (swapping of G and R residues), there is surprisingly a significant difference in the aggregation propensity and association number, both of which are greater for C16-CSK4GRDS. Both lipopeptides are cytocompatible (with fibroblasts and myoblasts) at low concentration, although cytotoxicity is noted at higher concentration.
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Dec 2024
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B24-Cryo Soft X-ray Tomography
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Diamond Proposal Number(s):
[30471, 33090]
Open Access
Abstract: Iron is a crucial element integral to various fundamental biological molecular mechanisms, including magnetosome biogenesis in magnetotactic bacteria (MTB). Magnetosomes are formed through the internalization and biomineralization of iron into magnetite crystals. However, the interconnected mechanisms by which MTB uptake and regulate intracellular iron for magnetosome biomineralization remain poorly understood, particularly at the single-cell level. To gain insights we employed a holistic multiscale approach, i.e., from elemental iron species to bacterial populations, to elucidate the interplay between iron uptake dynamics and magnetosome formation in Magnetospirillum gryphiswaldense MSR-1 under near-native conditions. We combined a correlative microscopy approach integrating light and X-ray tomography with analytical techniques, such as flow cytometry and inductively coupled plasma spectroscopy, to evaluate the effects of iron and oxygen availability on cellular growth, magnetosome biogenesis, and intracellular iron pool in MSR-1. Our results revealed that increased iron availability under microaerobic conditions significantly promoted the formation of longer magnetosome chains and increased intracellular iron uptake, with a saturation point at 300 μM iron citrate. Beyond this threshold, additional iron did not further extend the magnetosome chain length or increase total intracellular iron levels. Moreover, our work reveals (i) a direct correlation between the labile Fe2+ pool size and magnetosome content, with higher intracellular iron concentrations correlating with increased magnetosome production, and (ii) the existence of an intracellular iron pool, distinct from magnetite, persisting during all stages of biomineralization. This study offers insights into iron dynamics in magnetosome biomineralization at a single-cell level, potentially enhancing the industrial biomanufacturing of magnetosomes.
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Oct 2024
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