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Abstract: In this study we have investigated the nucleation mechanism of ‘sweet’, CO2 corrosion scale in situ using synchrotron scattering under industrially relevant conditions (CO2 saturated brine, ultra-low oxygen (8–32 ppb), 80 °C, pH 6.8, open-circuit-potential (OCP)). Simultaneous small and wide-angle X-Ray Scattering (SAXS-WAXS) measurement allows the phase and state of the nucleating corrosion scale to be characterised as a function of both immersion time and location with respect to the metal/solution interface. The results indicate that a precursor amorphous phase is formed prior to the emergence of a crystalline iron carbonate scale.

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Abstract: Despite being the most abundant sustainable energy resource, solar energy still faces major challenges in efficient capture and long-term storage. Molecular Solar Thermal Energy Storage (MOST) systems address this issue by employing photoswitchable molecules that absorb sunlight and store energy through reversible isomerization, cyclization or other intramolecular rearrangements. Azobenzenes are attractive due to their well-characterized photoresponsive behavior; however, conventional systems are hindered by low energy density, limited energy storage duration, and a reliance on organic solvents. Here, we present the Micellar Solar Thermal Energy Storage system (MIST) approach based on micellar aggregates that operate effectively across aqueous dispersions and gel states. These systems exhibit progressively enhanced energy storage lifetimes with increasing degrees of self-assembly, while delivering competitive energy densities. The thermal stability arises from restricted molecular mobility within the self-assembled structures and is enhanced on gelation, extending the calculated thermal half-life of the cis isomer from 148 days in dimethyl sulfoxide (DMSO), to 233 days in water, and to 12.8 years in the gel state. Compared to previous azobenzene-based MOST systems, our MIST approach offers significantly extended energy storage durations and improved material processability, including water-compatible formulations and, macroscopic heat release in the gel state (up to 5.7 °C).

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Abstract: Pulsed potential (PP) electrodeposition was utilized for the first time to fabricate three-dimensional (3D) platinum (Pt) nanostructures within phytantriol-based double diamond cubic templates, both with or without 20 % w/w Brij-56 as a pore swelling agent. Unlike conventional direct potential (DP) deposition, the PP approach yielded Pt nanostructures with markedly enhanced uniformity and superior lattice ordering. Small Angle X-ray Scattering (SAXS) revealed that PP-grown structures exhibited sharp, well-defined Bragg peaks corresponding to lattice parameters of 134.2 ± 2.1 Å without Brij-56 and 236.7 ± 2.5 Å with 20 % w/w Brij-56, whereas DP-grown structures showed broader, less distinct peaks with smaller lattice parameter (130.7 ± 1.9 Å and 197.1 ± 2.8 Å, respectively). Notably, In-situ SAXS measurements provided real-time insights into the evolution of 3D Pt nanostructures, enabling direct monitoring of orientational and lateral ordering within the templated phases. High resolution SEM further confirmed the superior quality of PP-grown structures, revealing highly ordered 3D nanowire network with uniform pore sizes of 89.5 ± 1.3 (without Brij-56) and 102.0 ± 0.7 Å (with 20 % w/w Brij-56). Overall, these findings highlight the effectiveness of PP electrodeposition in mitigating structural inhomogeneities, establishing it as a powerful strategy for fabricating well-ordered 3D Pt nanostructures.

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Abstract: The deposition of calcium phosphate mineral within a collagen matrix plays a pivotal role in the formation of bone and teeth, yet understanding its precise mechanism and time-dependence remains a significant challenge. Conventional approaches are often constrained to ex situ studies and as a result the intrinsic dynamics governing collagen mineralization remains unclear. To address this knowledge gap, we developed a custom thermal flow cell to enable in situ characterization using Raman spectroscopy and small/wide-angle X-ray scattering for comparable sample settings. This approach allowed us to monitor the intricate process of collagen matrix mineralization from the initial infiltration of precursor phases to the formation of intermediate phosphate phases, and ultimately to the predominant growth of hydroxyapatite. Our findings reveal a striking expansion of the collagen matrix during initial infiltration, followed by compression in the early stages of mineralization, likely driven by water expulsion, which suggests the development of pre-stress similar to that observed in bone. As mineralization progressed, the matrix expanded once again, correlated with crystal growth. Post-mortem analyses confirmed the presence of intrafibrillar mineralization, with remarkable agreement to bone formation at up to 9 h of mineralization before over-mineralization occurred. Our study further identified a tessellated mineralization pattern within the collagen matrix, a feature also seen in bone, pointing to a highly regulated physico-chemical control of the mineralization dynamics. These insights deepen our understanding of the fundamental processes governing bone mineralization with broad implications for designing advanced biomaterials.

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Abstract: Access to clean water in isolated regions remains a major challenge, particularly due to contamination by the five most prevalent heavy metals: Hg(II), Pb(II), Cd(II), As(III/V), and Cr(VI). Traditional sorbents are limited in their ability to capture all the “big five” heavy metals, since they occur as cationic, neutral, or anionic species under standard conditions. To address this challenge, we have integrated a thiol rich Zr(IV)- Metal-Organic Framework (MOF), namely BCM-1, into a soy protein (SPI) and chitin (CHI) sponge in order to engineer a 3D-hybrid water filter. The components and the composite systems were thoroughly characterised by conventional means. Additionally, neutron imaging was used to reveal the 3D-interconnected micro- to macroporous structure of the filters, while Small-Angle X-ray Scattering (SAXS) confirmed the presence of BCM-1 as monodisperse nanoparticles. The 3D-sponge combines mechanical stability, high permeability, and broad chemical affinity, allowing the efficient removal of all five heavy metals through simple adjustments of its activation conditions. Adsorption experiments demonstrated over 90 % removal for most target metals depending if the hybrid-sponge is employed as synthesised, or after activating at pH = 1. When tested with 1 ppm solutions, they exhibit adsorption efficiencies for Hg(II), Pb(II), Cd(II), As(V), and Cr(VI) of 60.8/100 %, 94.4/74.8 %, 15.7/69.1 %, 100/38.2 %, 5.7/100 %, and 13.5/97.4 %, before and after the activation of the 3D-sponge, respectively. The metrics are consistently maintained over three adsorption/desorption cycles in surface water samples. On the whole, this work provides a scalable and sustainable approach to combine biopolymers and MOFs for real-world water remediation applications and highlights the key role of their protonation state on their absorptive properties.