B21-High Throughput SAXS
I22-Small angle scattering & Diffraction
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Diamond Proposal Number(s):
[31800]
Open Access
Abstract: Stimuli-responsive polymeric vesicles offer a versatile platform for mimicking dynamic cell-like behaviors for synthetic cell applications. In this study, thermally responsive polymeric droplets derived from poly(ethylene oxide)-poly(butylene oxide) (PEO-PBO) polymersomes, aiming to create synthetic cell models that mimic key biological functions are developed. Upon heating, the nanoscale vesicles undergo fusion, transforming into sponge-like microscale droplets enriched with membrane features. By modulating the temperature, these droplets display dynamic properties such as contractility, temperature-induced fusion, and cargo trapping, including small molecules and bacteria, thereby demonstrating their ability to dynamically interface with biological entities. The findings demonstrate the potential of our sponge-like droplets in synthetic cell applications, contributing to the understanding of PEO-PBO polymersomes’ unique characteristics, expanding the capabilities of synthetic cell structures, and representing an exciting possibility for advancing soft matter engineering to cell-like behaviors.
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Mar 2025
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B21-High Throughput SAXS
I22-Small angle scattering & Diffraction
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Mohamed A. N.
Soliman
,
Abdulwahhab
Khedr
,
Tarsem
Sahota
,
Rachel
Armitage
,
Raymond
Allan
,
Katie
Laird
,
Natalie
Allcock
,
Fatmah I.
Ghuloum
,
Mahetab H.
Amer
,
Reem
Alazragi
,
Charlotte J. C.
Edwards-Gayle
,
Jacek K.
Wychowaniec
,
Attilio V.
Vargiu
,
Mohamed A.
Elsawy
Diamond Proposal Number(s):
[28287, 28806]
Open Access
Abstract: Guiding molecular assembly of peptides into rationally engineered nanostructures remains a major hurdle against the development of functional peptide-based nanomaterials. Various non-covalent interactions come into play to drive the formation and stabilization of these assemblies, of which electrostatic interactions are key. Here, the atomistic mechanisms by which electrostatic interactions contribute toward controlling self-assembly and lateral association of ultrashort β-sheet forming peptides are deciphered. Our results show that this is governed by charge distribution and ionic complementarity, both affecting the interaction patterns between charged residues: terminal, core, and/or terminal-to-core attraction/repulsion. Controlling electrostatic interactions enabled fine-tuning nanofiber morphology for the 16 examined peptides, resulting into versatile nanostructures ranging from extended thin fibrils and thick bundles to twisted helical “braids” and short pseudocrystalline nanosheets. This in turn affected the physical appearance and viscoelasticity of the formed materials, varying from turbid colloidal dispersions and viscous solutions to soft and stiff self-supportive hydrogels, as revealed from oscillatory rheology. Atomistic mechanisms of electrostatic interaction patterns were confirmed by molecular dynamic simulations, validating molecular and nanoscopic characterization of the developed materials. In essence, detailed mechanisms of electrostatic interactions emphasizing the impact of charge distribution and ionic complementarity on self-assembly, nanostructure formation, and hydrogelation are reported.
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Jan 2025
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I09-Surface and Interface Structural Analysis
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Diamond Proposal Number(s):
[33024]
Open Access
Abstract: With the increasing attention to energy storage solutions, a growing emphasis has been placed on environmentally compatible electrolytes tailored for lithium-ion batteries. This study investigates the surface behavior of Si wafers as model systems cycled with a fluorine-free electrolyte based on lithium bis(oxalato)borate (LiBOB), with and without the additive vinylene carbonate (VC). By utilizing operando X-ray reflectivity (XRR) and ex situ X-ray photoelectron spectroscopy (XPS), the intricate processes involved in solid electrolyte interphase (SEI) formation is elucidated, SiO2/Si (de)lithiation, and the impact of the VC additive. Three distinct stages in SEI evolution during lithiation and delithiation are identified: SEI formation, subsequent densification and growth, and decrease in SEI thickness during delithiation, which collectively demonstrate the breathing behavior of the SEI during cycling. The addition of VC is found to mitigate LiBOB decomposition during cycling and promote a smoother SEI layer. Moreover, lithium trapping within the Si wafer post-delithiation is observed for both electrolytes but to a lesser extent with the addition of VC. This study offers structural and chemical insights into the fundamental processes governing SEI formation and Si wafer (de)lithiation in LiBOB-based electrolytes, with implications for designing environmentally friendly lithium-ion batteries.
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Jan 2025
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B24-Cryo Soft X-ray Tomography
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Diamond Proposal Number(s):
[32901, 33390]
Abstract: Upon exposure to biological environments, nanoparticles are rapidly coated with biomolecules, predominantly proteins, which alter their colloidal stability, biodistribution, and cell interactions. Despite extensive efforts to investigate the nanoparticles' fate, only a few studies use high-resolution characterization methods that allow in-depth characterization, and the existing methodologies are unable to differentiate particles internalized at the onset of incubation from those taken up toward the end of an incubation period. In this study, these limitations related to incubation disparities are overcame and precisely monitored the spatiotemporal displacement of colloidally stable protein corona-coated nanoparticles within cells. An unprecedented application of cryogenic X-ray nanotomography, combined with high-resolution, super-resolution, and correlative microscopy techniques, revealed the migration of nanoparticles to the perinuclear region while monitoring the evolution of cellular organelles in fully hydrated cells under near-native conditions, without the need for contrasting agents. Notably, this tracking indicates the progressive fusion of vesicles carrying the nanoparticles intracellularly. This strategy demonstrates the potential for uncovering the temporal aspects of nanoparticle behavior within cells and can be adaptable to a wide range of nanoparticles and cell types, offering a versatile and powerful tool to follow nanoparticles in cellular environments.
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Dec 2024
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I06-Nanoscience (XPEEM)
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Denis
Gentili
,
Gabriele
Calabrese
,
Eugenio
Lunedei
,
Francesco
Borgatti
,
Seyed A.
Mirshokraee
,
Vasiliki
Benekou
,
Giorgio
Tseberlidis
,
Alessio
Mezzi
,
Fabiola
Liscio
,
Andrea
Candini
,
Giampiero
Ruani
,
Vincenzo
Palermo
,
Francesco
Maccherozzi
,
Maurizio
Acciarri
,
Enrico
Berretti
,
Carlo
Santoro
,
Alessandro
Lavacchi
,
Massimiliano
Cavallini
Open Access
Abstract: Defects are inherent in transition metal dichalcogenides and significantly affect their chemical and physical properties. In this study, surface defect electrochemical nanopatterning is proposed as a promising method to tune in a controlled manner the electronic and functional properties of defective MoS₂ thin films. Using parallel electrochemical nanolithography, MoS₂ thin films are patterned, creating sulphur vacancy-rich active zones alternated with defect-free regions over a centimetre scale area, with sub-micrometre spatial resolution. The patterned films display tailored optical and electronic properties due to the formation of sulphur vacancy-rich areas. Moreover, the effectiveness of defect nanopatterning in tuning functional properties is demonstrated by studying the electrocatalytic activity for the hydrogen evolution reaction.
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Nov 2024
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labSAXS-Offline SAXS and Sample Environment Development
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Diamond Proposal Number(s):
[32045]
Open Access
Abstract: The structural evolution of hierarchical structures of nanoscale biomolecules is crucial for the construction of functional networks in vivo and in vitro. Despite the ubiquity of these networks, the physical mechanisms behind their formation and self-assembly remains poorly understood. Here, this study uses photochemically cross-linked folded protein hydrogels as a model biopolymer network system, with a combined time-resolved rheology and small-angle x-ray scattering (SAXS) approach to probe both the load-bearing structures and network architectures respectively thereby providing a cross-length scale understanding of the network formation. Combining SAXS, rheology, and kinetic modeling, a dual formation mechanism consisting of a primary formation phase is proposed, where monomeric folded proteins create the preliminary protein network scaffold; and a subsequent secondary formation phase, where both additional intra-network cross-links form and larger oligomers diffuse to join the preliminary network, leading to a denser more mechanically robust structure. Identifying this as the origin of the structural and mechanical properties of protein networks creates future opportunities to understand hierarchical biomechanics in vivo and develop functional, designed-for-purpose, biomaterials.
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Nov 2024
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E02-JEM ARM 300CF
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Diamond Proposal Number(s):
[35560]
Open Access
Abstract: Nanofibrous active layers offer hierarchical control over molecular structure, and the size and distribution of electron donor:acceptor domains, beyond conventional organic photovoltaic architectures. This structure is created by forming donor pathways via electrospinning nanofibers of semiconducting polymer, then infiltrating with an electron acceptor. Electrospinning induces chain and crystallite alignment, resulting in enhanced light-harvesting and charge transport. Here, the charge transport capabilities are predicted, and charge separation and dynamics are evaluated in these active layers, to assess their photovoltaic potential. Through X-ray and electron diffraction, the fiber nanostructure is elucidated, with uniaxial elongation of the electrospinning jet aligning the polymer backbones within crystallites orthogonal to the fiber axis, and amorphous chains parallel. It is revealed that this structure forms when anisotropic crystallites, pre-assembled in solution, become oriented along the fiber– a configuration with high charge transport potential. Competitive dissociation of excitons formed in the photoactive nanofibers is recorded, with 95%+ photoluminescence quenching upon electron acceptor introduction. Transient absorption studies reveal that silver nanoparticle addition to the fibers improves charge generation and/or lifetimes. 1 ns post-excitation, the plasmonic architecture contains 45% more polarons, per exciton formed, than the bulk heterojunction. Therefore, enhanced exciton populations may be successfully translated into additional charge carriers.
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Nov 2024
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I19-Small Molecule Single Crystal Diffraction
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Diamond Proposal Number(s):
[35994]
Open Access
Abstract: Nucleation plays an important role in crystallization outcomes, but it is still poorly understood because it occurs on short timescales and small size scales. Consequently, nucleation mechanisms are still challenging to comprehend and predict. Gaining a better understanding, and potentially control, over nucleation pathways, can significantly aid toward more consistent and targeted crystallization outcomes. To achieve this, facile methods that allow for an accurate depiction and analysis of nucleus-sized clusters are needed. Herein, the use of crystalline metal–organic frameworks (MOFs) is reported to entrap clusters of small organic molecules, allowing for an accurate representation of the size and shape of the confined clusters via single-crystal X-Ray diffraction analysis. This is realized by synthesizing high-quality single crystals of lanthanum-based MOFs, which provides well-defined pore spaces for the encapsulation of guest molecules. The results show that the size and shape of the guest molecular clusters within MOFs significantly differ from their bulk equivalents, suggesting that this method can also be used toward discovering novel polymorphs. Additionally, the findings indicate that these small molecular clusters form via intermolecular interactions that do not always dominate the bulk packing, shedding new light on the initial molecular aggregation mechanisms of precritical nuclei.
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Sep 2024
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B18-Core EXAFS
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Diamond Proposal Number(s):
[33476]
Open Access
Abstract: Herein, the synthesis and characterization of two robust tungsten and rhenium carbonyl complexes integrated into an organic polymer (CPP-Re, CPP-W) are reported. These polymers are obtained by a Suzuki coupling reaction between the corresponding dibromo metal-carbonyl substituted dipyrido[3,2-a:2′,3′-c]phenazine complex and 1,3,5-triphenylbenzene-4′,4″,4″,4‴-triboronic acid and integrated catalytic active sites and photosensitizer since they have not only nitrogen sites to coordinate metal active centers as rhenium or tungsten but photoactive units with good charge-separating ability which can significantly improve the CO2 photoreduction reaction (CO2PRR). These polymers show similar activity in solid–gas CO2PRR in absence of sacrificial agents to produce syn gas (CO + H2) but CPP-W selectivity to products change regarding CPP-Re being able to produce also large amount of more demanding electron products such as methane and ethane. Moreover, the single-site Re- or W-CPP catalysts could prevent the dimerization of complexes that produces its deactivation. This work shows the potential of CPPs as matrices to support single active centers for heterogeneous catalysis.
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Sep 2024
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I15-1-X-ray Pair Distribution Function (XPDF)
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Vahid
Nozari
,
Ayda Nemati Vesali
Azar
,
Roman
Sajzew
,
Celia
Castillo-Blas
,
Ayano
Kono
,
Martin
Oschatz
,
David A.
Keen
,
Philip A.
Chater
,
Georgina P.
Robertson
,
James M. A.
Steele
,
Luis
León-Alcaide
,
Alexander
Knebel
,
Christopher W.
Ashling
,
Thomas D.
Bennett
,
Lothar
Wondraczek
Diamond Proposal Number(s):
[29957]
Open Access
Abstract: Metal-organic framework (MOF) composite materials containing ionic liquids (ILs) have been proposed for a range of potential applications, including gas separation, ion conduction, and hybrid glass formation. Here, an order transition in an IL@MOF composite is discovered using CuBTC (copper benzene-1,3,5-tricarboxylate) and [EMIM][TFSI] (1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide). This transition – absent for the bare MOF or IL – provides an extended super-cooling range and latent heat at a capacity similar to that of soft paraffins, in the temperature range of ≈220 °C. Structural analysis and in situ monitoring indicate an electrostatic interaction between the IL molecules and the Cu paddle-wheels, leading to a decrease in pore symmetry at low temperature. These interactions are reversibly released above the transition temperature, which reflects in a volume expansion of the MOF-IL composite.
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Jul 2024
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